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                                                                   Exhibit 10.22
--------------------------------------------------------------------------------




                              OCEAN ENERGY, INC.

                             SUBSIDIARY GUARANTORS

                                parties hereto

                                      AND

                     U.S. BANK TRUST NATIONAL ASSOCIATION

                                    Trustee


                           -------------------------

                                   Indenture


                           Dated as of July 8, 1998


                           -------------------------


                                 $250,000,000


              8 3/8% Series A Senior Subordinated Notes due 2008

              8 3/8% Series B Senior Subordinated Notes due 2008
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                               TABLE OF CONTENTS
 
 
                                                                            Page
 
ARTICLE I  DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION.............2
Section  1.1   Definitions.....................................................2
Section  1.2   Other Definitions..............................................34
Section  1.3   Incorporation by Reference of Trust Indenture Act..............35
Section  1.4   Rules of Construction..........................................35

ARTICLE II  SECURITY FORMS....................................................36
Section  2.1   Forms Generally................................................36
Section  2.2   Form of Face of Security.......................................36
Section  2.3   Form of Reverse of Security....................................40
Section  2.4   Form of Notation Relating to Subsidiary Guarantees.............48
Section  2.5   Form of Trustee's Certificate of Authentication................49

ARTICLE III  THE SECURITIES...................................................50
Section  3.1   Title and Terms................................................50
Section  3.2   Denominations..................................................50
Section  3.3   Execution, Authentication, Delivery and Dating.................50
Section  3.4   Temporary Securities...........................................52
Section  3.5   Registration, Registration of Transfer and Exchange............52
Section  3.6   Transfer and Exchange..........................................52
Section  3.7   Additional Provisions for Global Security......................60
Section  3.8   Mutilated, Destroyed, Lost and Stolen Securities...............61
Section  3.9   Payment of Interest; Interest Rights Preserved.................61
Section  3.10  Persons Deemed Owners..........................................62
Section  3.11  Cancellation...................................................63
Section  3.12  Computation of Interest........................................63
Section  3.13  CUSIP Numbers..................................................63

ARTICLE IV  SATISFACTION AND DISCHARGE........................................63
Section  4.1   Satisfaction and Discharge of Indenture........................63
Section  4.2   Application of Trust Money.....................................64

ARTICLE V  REMEDIES...........................................................65
Section  5.1   Events of Default..............................................65
Section  5.2   Acceleration of Maturity; Rescission and Annulment.............67
Section  5.3   Collection of Indebtedness and Suits for Enforcement by
               Trustee........................................................68
Section  5.4   Trustee May File Proofs of Claim...............................69


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Section  5.5   Trustee May Enforce Claims Without Possession of Securities....69
Section  5.6   Application of Money Collected.................................70
Section  5.7   Limitation on Suits............................................70
Section  5.8   Unconditional Right of Holders to Receive Principal,
               Premium and Interest...........................................71
Section  5.9   Restoration of Rights and Remedies.............................71
Section  5.10  Rights and Remedies Cumulative.................................71
Section  5.11  Delay or Omission Not Waiver...................................71
Section  5.12  Control by Holders.............................................71
Section  5.13  Waiver of Past Defaults........................................72
Section  5.14  Waiver of Stay, Extension or Usury Laws........................72

ARTICLE VI  THE TRUSTEE.......................................................72
Section  6.1   Notice of Defaults.............................................72
Section  6.2   Certain Rights and Duties of Trustee...........................73
Section  6.3   Trustee Not Responsible for Recitals or Issuance of
               Securities.....................................................75
Section  6.4   May Hold Securities............................................75
Section  6.5   Money Held in Trust............................................75
Section  6.6   Compensation and Reimbursement.................................75
Section  6.7   Corporate Trustee Required; Eligibility........................76
Section  6.8   Conflicting Interests..........................................76
Section  6.9   Resignation and Removal; Appointment of Successor..............77
Section  6.10  Acceptance of Appointment by Successor.........................78
Section  6.11  Merger, Conversion, Consolidation or Succession to Business....78
Section  6.12  Preferential Collection of Claims Against Company..............79

ARTICLE VII  HOLDERS' LISTS AND REPORTS BY TRUSTEE............................79
Section  7.1   Disclosure of Names and Addresses of Holders...................79
Section  7.2   Reports By Trustee.............................................79

ARTICLE VIII  CONSOLIDATION, MERGER, CONVEYANCE,
               TRANSFER OR LEASE..............................................79
Section  8.1   Company May Consolidate, etc., Only on Certain Terms...........79
Section  8.2   Successor Substituted..........................................81

ARTICLE IX  SUPPLEMENTAL INDENTURES...........................................81
Section  9.1   Supplemental Indentures Without Consent of Holders.............81
Section  9.2   Supplemental Indenture with Consent of Holders.................82
Section  9.3   Execution of Supplemental Indentures...........................83
Section  9.4   Effect of Supplemental Indentures..............................83
Section  9.5   Conformity With Trust Indenture Act............................83
Section  9.6   Reference in Securities to Supplemental Indentures.............83
Section  9.7   Notice of Supplemental Indentures..............................84


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ARTICLE X  COVENANTS..........................................................84
Section  10.1  Payment of Principal, Premium, if any, and Interest............84
Section  10.2  Maintenance of Office or Agency................................84
Section  10.3  Money for Security Payments to Be Held in Trust................85
Section  10.4  Corporate Existence............................................86
Section  10.5  Payment of Taxes and Other Claims..............................86
Section  10.6  Maintenance of Properties......................................86
Section  10.7  Insurance......................................................87
Section  10.8  Statement by Officers as to Default............................87
Section  10.9  Provision of Financial Information.............................87
Section  10.10 Limitation on Other Senior Subordinated Indebtedness...........88
Section  10.11 Limitation on Restricted Payments..............................88
Section  10.12 Limitation on Indebtedness.....................................92
Section  10.13 Limitation on Guarantees of Indebtedness by Subsidiaries;
                Additional Subsidiary Guarantors..............................92
Section  10.14 Limitation on Issuances and Sale of Capital Stock by
                Restricted Subsidiaries.......................................93
Section  10.15 Limitation on Liens............................................94
Section  10.16 Purchase of Securities Upon Change of Control..................94
Section  10.17 Disposition of Proceeds of Asset Sales.........................96
Section  10.18 Limitation on Transactions with Affiliates.....................98
Section  10.19 Limitation on Dividend and Other Payment Restrictions
                Affecting Restricted Subsidiaries.............................99
Section  10.20 Limitation on Restrictive Covenants...........................100
Section  10.21 Waiver of Certain Covenants...................................100
Section  10.22 Suspension of Certain Covenants...............................100

ARTICLE XI  REDEMPTION OF SECURITIES.........................................101
Section  11.1  Right of Redemption...........................................101
Section  11.2  Applicability of Article......................................101
Section  11.3  Election to Redeem; Notice to Trustee.........................101
Section  11.4  Selection by Trustee of Securities to Be Redeemed.............102
Section  11.5  Notice of Redemption..........................................102
Section  11.6  Deposit of Redemption Price...................................102
Section  11.7  Securities Payable on Redemption Date.........................103
Section  11.8  Securities Redeemed in Part...................................103

ARTICLE XII  DEFEASANCE AND COVENANT DEFEASANCE..............................103
Section  12.1  Company's Option to Effect Defeasance or Covenant
                Defeasance...................................................103
Section  12.2  Defeasance and Discharge......................................103
Section  12.3  Covenant Defeasance...........................................104
Section  12.4  Conditions to Defeasance or Covenant Defeasance...............104


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Section  12.5  Deposited Money and U.S. Government Obligations to Be Held
                in Trust; Other Miscellaneous Provisions.....................106
Section  12.6  Reinstatement.................................................107

ARTICLE XIII  GUARANTEES.....................................................107
Section  13.1  Unconditional Guarantee.......................................107
Section  13.2  Subsidiary Guarantors May Consolidate, etc., on Certain
                Terms........................................................108
Section  13.3  Release of a Subsidiary Guarantor.............................109
Section  13.4  Limitation of Subsidiary Guarantor's Liability................110
Section  13.5  Contribution..................................................110
Section  13.6  Execution and Delivery of Notation of Subsidiary Guarantee....110
Section  13.7  Severability..................................................111
Section  13.8  Subsidiary Guarantees Subordinated to Guarantor
                Senior Indebtedness..........................................111
Section  13.9  Subsidiary Guarantors Not to Make Payments with Respect to
                Subsidiary Guarantees in Certain Circumstances...............111
Section  13.10 Subsidiary Guarantees Subordinated to Prior Payment of All
                Guarantor Senior Indebtedness upon Dissolution, etc..........113
Section  13.11 Holders to be Subrogated to Rights of Holders of Guarantor
                Senior Indebtedness..........................................114
Section  13.12 Obligations of the Subsidiary Guarantors Unconditional........114
Section  13.13 Trustee Entitled to Assume Payments Not Prohibited in
                Absence of Notice............................................115
Section  13.14 Application by Trustee of Money Deposited with it.............115
Section  13.15 Subordination Rights Not Impaired by Acts of Omissions
                of Subsidiary Guarantors or Holders of Guarantor
                Senior Indebtedness..........................................116
Section  13.16 Holders Authorize Trustee to Effectuate Subordination of
                Subsidiary Guarantees........................................116
Section  13.17 Right of Trustee to Hold Guarantor Senior Indebtedness........116
Section  13.18 Article XIII Not to Prevent Events of Default.................117
Section  13.19 Payment.......................................................117

ARTICLE XIV  SUBORDINATION OF SECURITIES.....................................117
Section  14.1  Securities Subordinate to Senior Indebtedness.................117
Section  14.2  Payment Over of Proceeds upon Dissolution, etc................117
Section  14.3  Suspension of Payment When Senior Indebtedness in Default.....118
Section  14.4  Trustee's Relation to Senior Indebtedness.....................120
Section  14.5  Subrogation to Rights of Holders of Senior Indebtedness.......120
Section  14.6  Provisions Solely To Define Relative Rights...................120
Section  14.7  Trustee To Effectuate Subordination...........................121
Section  14.8  Waiver of Subordination Provision.............................121
Section  14.9  Notice to Trustee.............................................122



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Section  14.10 Reliance on Judicial Order or Certificate of Liquidating
                Agent........................................................123
Section  14.11 Rights of Trustee as Holder of Senior Indebtedness;
                Preservation of Trustee's Rights.............................123
Section  14.12 Article Applicable to Paying Agents...........................123
Section  14.13 No Suspension of Remedies.....................................123

ARTICLE XV  MISCELLANEOUS....................................................124
Section  15.1  Compliance Certificates and Opinions..........................124
Section  15.2  Form of Documents Delivered to Trustee........................124
Section  15.3  Acts of Holders...............................................125
Section  15.4  Notices, etc. to Trustee, Company and Subsidiary Guarantors...126
Section  15.5  Notice to Holders; Waiver.....................................126
Section  15.6  Effect of Headings and Table of Contents......................127
Section  15.7  Successors and Assigns........................................127
Section  15.8  Separability Clause...........................................127
Section  15.9  Benefits of Indenture.........................................127
Section  15.10 Governing Law; Trust Indenture Act Controls...................127
Section  15.11 Legal Holidays................................................128
Section  15.12 No Recourse Against Others....................................128
Section  15.13 Duplicate Originals...........................................128
Section  15.14 No Adverse Interpretation of Other Agreements.................128



                                       v
<PAGE>
 
     INDENTURE, dated as of July 8, 1998 between OCEAN ENERGY, INC., a Delaware
corporation (hereinafter called the "Company"), the SUBSIDIARY GUARANTORS (as
defined hereinafter) and U.S. BANK TRUST NATIONAL ASSOCIATION, as trustee
(hereinafter called the "Trustee").


                            RECITALS OF THE COMPANY

     Each party agrees as follows for the benefit of the other party and for the
equal and ratable benefit of the Holders of the Company's 8 3/8% Series A Senior
Subordinated Notes due 2008 (the "Series A Securities") and the Company's 8 3/8%
Series B Senior Subordinated Notes due 2008 (the "Series B Securities" and,
collectively with the Series A Securities, the "Securities" or each, a
"Security").

     The Company owns beneficially and of record all of the equity ownership of
the outstanding Voting Stock of the initial Subsidiary Guarantor, and the
initial Subsidiary Guarantor is a member of the Company's consolidated group of
companies that are engaged in related businesses.  The initial Subsidiary
Guarantor will derive direct and indirect benefit from the issuance of the
Securities; accordingly, the initial Subsidiary Guarantor has authorized its
guarantee of the Company's obligations under this Indenture and the Securities,
and to provide therefor the initial Subsidiary Guarantor has duly authorized the
execution and delivery of this Indenture.

     This Indenture is subject to the provisions of the Trust Indenture Act of
1939, as amended, that are required to be part of this Indenture and shall, to
the extent applicable, be governed by such provisions.

     All things necessary have been done to make the Securities, when executed
by the Company and authenticated and delivered hereunder and duly issued by the
Company, the valid obligations of the Company, to make the Subsidiary Guarantee
contained in this Indenture, when executed by the Subsidiary Guarantor, the
valid obligation of the Subsidiary Guarantor and to make this Indenture a valid
agreement of the Company, the Subsidiary Guarantor and the Trustee, in
accordance with their and its terms.

     NOW, THEREFORE, THIS INDENTURE WITNESSETH:

     For and in consideration of the premises and the purchase of the Securities
(together with the related Subsidiary Guarantee) by the Holders thereof, it is
mutually covenanted and agreed, for the equal and proportionate benefit of all
Holders of the Securities (together with the related Subsidiary Guarantee), as
follows:

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                                   ARTICLE I

            DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION
            -------------------------------------------------------

     Section 1.1   Definitions.

     "Acquired Indebtedness" means Indebtedness of a Person (a) assumed in
connection with an Asset Acquisition from such Person, (b) outstanding at the
time such Person becomes a Subsidiary of any other Person (other than any
Indebtedness incurred in connection with, or in contemplation of, such Asset
Acquisition or such Person becoming such a Subsidiary) or (c) any renewals,
extensions, substitutions, refinancings or replacements (each, for purposes of
this clause, a "refinancing") by the Company of any Indebtedness described in
clause (a) or (b) of this definition, including any successive refinancings, so
long as (i) any such new Indebtedness shall be a principal amount that does not
exceed the principal amount (or, if such Indebtedness being refinanced provides
for an amount less than the principal amount thereof to be due and payable upon
a declaration of acceleration thereof, such lesser amount as of the date of
determination) so refinanced plus the amount of any premium required to be paid
in connection with such refinancing pursuant to the terms of the Indebtedness
refinanced or the amount of any premium reasonably determined by the Company as
necessary to accomplish such refinancing, plus the amount of expenses of the
Company incurred in connection with such refinancing, and (ii) in the case of
any refinancing of Subordinated Indebtedness, such new Indebtedness is made
subordinate to the Securities at least to the same extent as the Indebtedness
being refinanced and (iii) such new Indebtedness has an Average Life longer than
the Average Life of the Securities and a final Stated Maturity later than the
final Stated Maturity of the Securities.

     "Act," when used with respect to any Holder, has the meaning specified in
Section 15.3.

     "Adjusted Consolidated Net Tangible Assets" means (without duplication), as
of the date of determination, (a) the sum of (i) discounted future net revenues
from proved oil and gas reserves of the Company and its Restricted Subsidiaries
calculated in accordance with SEC guidelines before any state or federal income
taxes, with no less than 70% of such discounted future net revenues estimated or
audited by one or more nationally recognized firms of independent petroleum
engineers in a reserve report prepared as of the end of the Company's most
recently completed fiscal year, as increased by, as of the date of
determination, the estimated discounted future net revenues from (A) estimated
proved oil and gas reserves acquired since the date of such year-end reserve
report, and (B) estimated oil and gas reserves attributable to upward revisions
of estimates of proved oil and gas reserves since the date of such year-end
reserve report due to exploration, development or exploitation activities, in
each case calculated in accordance with SEC guidelines (utilizing the prices
utilized in such year-end reserve report), and decreased by, as of the date of
determination, the estimated discounted future net revenues from (C) estimated
proved oil and gas reserves produced or disposed of since the date of such year-
end reserve report and (D) estimated oil and gas reserves attributable to
downward revisions of estimates of proved oil and gas reserves since the date of
such year-end reserve report due to changes in geological conditions or other
factors which would, in

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accordance with standard industry practice, cause such revisions, in each case
calculated in accordance with SEC guidelines (utilizing the prices utilized in
such year-end reserve report); provided that, in the case of each of the
determinations made pursuant to clauses (A) through (D), such increases and
decreases shall be as estimated by the Company's petroleum engineers, unless in
the event that there is a Material Change as a result of such acquisitions,
dispositions or revisions, then the discounted future net revenues utilized for
purposes of this clause (a)(i) shall be confirmed in writing by estimate or
audit of one or more nationally recognized firms of independent petroleum
engineers as to at least 70% of such discounted future net revenues, (ii) the
capitalized costs that are attributable to oil and gas properties of the Company
and its Restricted Subsidiaries to which no proved oil and gas reserves are
attributable, based on the Company's books and records as of a date no earlier
than the date of the Company's latest annual or quarterly financial statements,
(iii) the Net Working Capital on a date no earlier than the date of the
Company's latest annual or quarterly financial statements and (iv) the greater
of (A) the net book value on a date no earlier than the date of the Company's
latest annual or quarterly financial statements or (B) the appraised value, as
estimated by independent appraisers, of other tangible assets (including,
without duplication, Investments in unconsolidated Restricted Subsidiaries) of
the Company and its Restricted Subsidiaries, as of the date no earlier than the
date of the Company's latest audited financial statements, minus (b) the sum of
(i) minority interests, (ii) any gas balancing liabilities of the Company and
its Restricted Subsidiaries reflected in the Company's latest audited financial
statements, (iii) to the extent included in (a) (i) above, the discounted future
net revenues, calculated in accordance with SEC guidelines (utilizing the prices
utilized in the Company's year-end reserve report), attributable to reserves
which are required to be delivered to third parties to fully satisfy the
obligations of the Company and its Restricted Subsidiaries with respect to
Volumetric Production Payments on the schedules specified with respect thereto
and (iv) the discounted future net revenues, calculated in accordance with SEC
guidelines, attributable to reserves subject to Dollar-Denominated Production
Payments which, based on the estimates of production and price assumptions
included in determining the discounted future net revenues specified in (a)(i)
above, would be necessary to fully satisfy the payment obligations of the
Company and its Restricted Subsidiaries with respect to Dollar-Denominated
Production Payments on the schedules specified with respect thereto. If the
Company changes its method of accounting from the full cost method to the
successful efforts method or a similar method of accounting, "Adjusted
Consolidated Net Tangible Assets" will continue to be calculated as if the
Company was still using the full cost method of accounting.

     "Adjusted Net Assets" of a Subsidiary Guarantor at any date shall mean the
amount by which the fair value of the properties and assets of such Subsidiary
Guarantor exceeds the total amount of liabilities, including, without
limitation, contingent liabilities (after giving effect to all other fixed and
contingent liabilities incurred or assumed on such date), but excluding
liabilities under the Subsidiary Guarantee, of such Subsidiary Guarantor at such
date.

     "Affiliate" means, with respect to any specified Person, any other Person
directly or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person. For the purposes of this definition,
"control," when used with respect to any Person, means the power to direct the
management and policies of such Person, directly or indirectly, whether

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through the ownership of voting securities, by contract or otherwise; and the
terms "controlling" and "controlled" have meanings correlative to the foregoing.
For purposes of this definition, beneficial ownership of 10% or more of the
voting common equity (on a fully diluted basis) or options or warrants to
purchase such equity (but only if exercisable at the date of determination or
within 60 days thereof) of a Person shall be deemed to constitute control of
such Person.

     "Asset Acquisition" means (a) an Investment by the Company or any
Restricted Subsidiary in any other Person pursuant to which such Person shall
become a Restricted Subsidiary or any Restricted Subsidiary shall be merged with
or into the Company or any other Restricted Subsidiary or (b) the acquisition by
the Company or any Restricted Subsidiary of the assets of any Person which
constitute all or substantially all of the assets of such Person or any division
or line of business of such Person.

     "Asset Sale" means any sale, issuance, conveyance, transfer, lease or other
disposition to any Person other than the Company or any of its Restricted
Subsidiaries (including, without limitation, by means of a Sale/ Leaseback
Transaction or by way of merger or consolidation) (collectively, for purposes of
this definition, a "transfer"), directly or indirectly, in one or a series of
related transactions, of (a) any Capital Stock of any Restricted Subsidiary (or
North American Unrestricted Subsidiary) held by the Company or any Restricted
Subsidiary (or North American Unrestricted Subsidiary); (b) all or substantially
all of the properties and assets of any division or line of business of the
Company or any of its Restricted Subsidiaries (or North American Unrestricted
Subsidiaries); or (c) any other properties or assets of the Company or any of
its Restricted Subsidiaries (or North American Unrestricted Subsidiaries) other
than (A) a transfer of hydrocarbons or other mineral products, cash or Cash
Equivalents in the ordinary course of business or (B) any lease, abandonment,
disposition, relinquishment or farm-out of any oil and gas Property in the
ordinary course of business. For the purposes of this definition, the term
"Asset Sale" shall not include (i) any transfer of properties or assets that is
governed by, and made in accordance with, the provisions described in 
Section 8.1 hereof; (ii) any transfer of properties or assets to an Unrestricted
Subsidiary, if permitted under Section 10.11 hereof; (iii) any trade or exchange
by the Company or any Restricted Subsidiary (or North American Unrestricted
Subsidiary) of oil and gas properties for other oil and gas properties owned or
held by another Person which the Board of Directors of the Company determines in
good faith to be of approximately equivalent value; (iv) any transfer of
Properties having a fair market value of less than $5,000,000; or (v) any
transfer that is a Permitted Investment, a Restricted Payment not prohibited by
Section 10.11 hereof or an investment specifically excluded from the definition
of the term "Investment."

     "Attributable Indebtedness" means, with respect to any particular lease
under which any Person is at the time liable and at any date as of which the
amount thereof is to be determined, the present value of the total net amount of
rent required to be paid by such Person under the lease during the primary term
thereof, without giving effect to any renewals at the option of the lessee,
discounted from the respective due dates thereof to such date of determination
at the rate of interest per annum implicit in the terms of the lease. As used in
the preceding sentence, the "net amount of rent" under any lease for any such
period shall mean the sum of rental and other payments required

                                       4
<PAGE>
 
to be paid with respect to such period by the lessee thereunder, excluding any
amounts required to be paid by such lessee on account of maintenance and
repairs, insurance, taxes, assessments, water rates or similar charges. In the
case of any lease which is terminable by the lessee upon payment of a penalty,
such net amount of rent shall also include the amount of such penalty, but no
rent shall be considered as required to be paid under such lease subsequent to
the first date upon which it may be so terminated.

     "Average Life" means, with respect to any Indebtedness, at any date of
determination, the quotient obtained by dividing (a) the sum of the products of
(i) the number of years (and any portion thereof) from the date of determination
to the date or dates of each successive scheduled principal payment (including,
without limitation, any sinking fund or mandatory redemption payment
requirements) of such Indebtedness multiplied by (ii) the amount of each such
principal payment by (b) the sum of all such principal payments.

     "Bank Agent" means Chase Bank of Texas, National Association or any
successor or replacement agent under the Credit Agreement.

     "Board of Directors" means, with respect to the Company, either the board
of directors of the Company or any duly authorized committee of such board of
directors, and, with respect to any Restricted Subsidiary, either the board of
directors of such Restricted Subsidiary or any duly authorized committee of that
board.

     "Board Resolution" means a copy of a resolution certified by the Secretary
or an Assistant Secretary of the Company to have been duly adopted by its Board
of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee, and with respect to a Restricted
Subsidiary, a copy of a resolution certified by the Secretary or an Assistant
Secretary of such Restricted Subsidiary to have been duly adopted by its Board
of Directors and to be in full force and effect on the date of such
certification, and delivered to the Trustee.

     "Business Day" means each Monday, Tuesday, Wednesday, Thursday and Friday
which is not a day on which banking institutions in the Borough of Manhattan,
The City of New York, New York or the city in which the Trustee's Corporate
Trust Office is located, are authorized or obligated by law or executive order
to close.

     "Capital Stock" means, with respect to any Person, any and all shares,
interests, participations, rights in or other equivalents in the equity
interests (however designated) in such Person, and any rights (other than debt
securities convertible into an equity interest), warrants or options exercisable
for, exchangeable for or convertible into such an equity interest in such
Person.

     "Capitalized Lease Obligation" means any obligation to pay rent or other
amounts under a lease of (or other agreement conveying the right to use) any
Property (whether real, personal or mixed) that is required to be classified and
accounted for as a capital lease obligation under GAAP,

                                       5
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and, for the purpose of this Indenture, the amount of such obligation at any
date shall be the capitalized amount thereof at such date, determined in
accordance with GAAP.

     "Cash Equivalents" means (i) any evidence of Indebtedness with a maturity
of 365 days or less issued or directly and fully guaranteed or insured by the
United States of America or any agency or instrumentality thereof (provided that
the full faith and credit of the United States of America is pledged in support
thereof); (ii) demand and time deposits and certificates of deposit or
acceptances with a maturity of 365 days or less of any financial institution
organized in the United States that is a member of the Federal Reserve System
having combined capital and surplus and undivided profits of not less than
$500,000,000 or any commercial bank organized under the laws of any other
country that is a member of the Organization for Economic Cooperation and
Development ("OECD") and has total assets in excess of $500,000,000; (iii)
direct obligations issued by any state of the United States of America or Canada
or any political subdivision of any such state or Canada or any public
instrumentality of any such state or Canada maturing within 90 days after the
date of acquisition thereof and, at the time of acquisition, having one of the
two highest ratings obtainable from either S&P or Moody's (or, if at any time
neither S&P nor Moody's shall be rating such obligations, then from such other
rating service as may be acceptable to the Trustee); (iv) commercial paper
issued by a corporation that is not an Affiliate of the Company and is organized
under the laws of any state of the United States or the District of Columbia and
rated at least A- 1 by S&P or at least P- 1 by Moody's; (v) repurchase
obligations with a term of not more than seven days for underlying securities of
the types described in clause (i) above entered into with any commercial bank
meeting the specifications of clause (ii) above; (vi) overnight bank deposits
and bankers' acceptances at any commercial bank meeting the qualifications
specified in clause (ii) above; (vii) deposits available for withdrawal on
demand with any commercial bank not meeting the qualifications specified in
clause (ii) above but which is organized under the laws of (a) any country that
is a member of the OECD and has total assets in excess of $50,000,000 or (b) any
other country in which the Company or any Restricted Subsidiary maintains an
office or is engaged in the Oil and Gas Business, provided that, in either case
(A) all such deposits are required to be made in such accounts in the ordinary
course of business, (B) such deposits do not at any one time exceed $5,000,000
in the aggregate and (C) no funds so deposited remain on deposit in such bank
for more than 30 days; (viii) deposits available for withdrawal on demand with
any commercial bank not meeting the qualifications specified in clause (ii)
above but which is a lending bank under any of the Company's or any Restricted
Subsidiary's credit facilities, provided all such deposits do not exceed
$5,000,000 in the aggregate at any one time; (ix) deposits at any one time not
in excess of $200,000 in the aggregate, available for withdrawal on demand, with
any commercial bank organized in the United States, and not meeting the
qualifications specified in clause (ii) above; and (x) investments in money
market funds substantially all of whose assets comprise securities of the types
described in clauses (i) through (vi).

     "Change of Control" means the occurrence of any of the following events:
(a) any "person" or "group" (as such terms are used in Sections 13(d) and 14(d)
of the Exchange Act) is or becomes the "beneficial owner" (as defined in Rule
13d-3 under the Exchange Act), directly or indirectly, of more than 50% of the
total Voting Stock of the Company; (b) the Company is merged with or into

                                       6
<PAGE>
 
or consolidated with another Person and, immediately after giving effect to the
merger or consolidation, (A) less than 50% of the total voting power of the
outstanding Voting Stock of the surviving or resulting Person is then
"beneficially owned" (within the meaning of Rule 13d-3 under the Exchange Act)
in the aggregate by (x) the stockholders of the Company immediately prior to
such merger or consolidation, or (y) if a record date has been set to determine
the stockholders of the Company entitled to vote with respect to such merger or
consolidation, the stockholders of the Company as of such record date and (B)
any "person" or "group" (as defined in Section 13(d)(3) or 14(d)(2) of the
Exchange Act, has become the direct or indirect "beneficial owner" (as defined
in Rule 13d-3 under the Exchange Act) of more than 50% of the total voting power
of the Voting Stock of the surviving or resulting Person; (c) the Company,
either individually or in conjunction with one or more Restricted Subsidiaries,
sells, conveys, transfers or leases, or the Restricted Subsidiaries sell,
convey, transfer or lease, all or substantially all of the assets of the Company
and the Restricted Subsidiaries, taken as a whole (either in one transaction or
a series of related transactions), including Capital Stock of the Restricted
Subsidiaries, to any Person (other than the Company or a Wholly Owned Restricted
Subsidiary) (but in no event shall the sale, conveyance, transfer or lease of
the assets of, or the Capital Stock of, a North American Restricted Subsidiary,
in the absence of other factors, result in a Change of Control); (d) during any
consecutive two-year period, individuals who at the beginning of such period
constituted the Board of Directors of the Company (together with any new
directors whose election by such Board of Directors or whose nomination for
election by the stockholders of the Company was approved by a vote of a majority
of the directors then still in office who were either directors at the beginning
of such period or whose election or nomination for election was previously so
approved) cease for any reason to constitute a majority of the Board of
Directors of the Company then in office; or (e) the liquidation or dissolution
of the Company.

     "Code" shall mean the Internal Revenue Code of 1986, as amended, as now or
hereafter in effect, together with all regulations, rulings and interpretations
thereof or thereunder issued by the Internal Revenue Service.

     "Commission" or "SEC" means the Securities and Exchange Commission, as from
time to time constituted, created under the Exchange Act, or, if at any time
after the execution of this Indenture such Commission is not existing and
performing the duties now assigned to it under the Trust Indenture Act, then the
body performing such duties at such time.

     "Common Stock" of any Person means Capital Stock of such Person that does
not rank prior, as to the payment of dividends or as to the distribution of
assets upon any voluntary or involuntary liquidation, dissolution or winding up
of such Person, to shares of Capital Stock of any other class of such Person.

     "Company" means the Person named as the "Company" in the first paragraph of
this Indenture, until a successor Person shall have become such pursuant to the
applicable provisions of this Indenture, and thereafter "Company" shall mean
such successor Person.

                                       7
<PAGE>
 
     "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by its Chairman, its President, any Vice
President, its Treasurer or an Assistant Treasurer, and delivered to the
Trustee.

     "Consolidated Exploration Expenses" means, for any period, exploration
expenses of the Company and its Restricted Subsidiaries for such period as
determined on a consolidated basis in accordance with GAAP.

     "Consolidated Fixed Charge Coverage Ratio" means, for any period, the ratio
of (a) the sum of Consolidated Net Income, Consolidated Interest Expense,
Consolidated Exploration Expenses, Consolidated Income Tax Expense and
Consolidated Non-cash Charges deducted in computing Consolidated Net Income, in
each case, for such period, of the Company and its Restricted Subsidiaries on a
consolidated basis, all determined in accordance with GAAP, decreased (to the
extent included in determining Consolidated Net Income) by the sum of (x) the
amount of deferred revenues that are amortized during such period and are
attributable to reserves that are subject to Volumetric Production Payments and
(y) amounts recorded in accordance with GAAP as repayments of principal and
interest pursuant to Dollar-Denominated Production Payments, to (b) the sum of
such Consolidated Interest Expense for such period; provided that (i) in making
such computation, the Consolidated Interest Expense attributable to interest on
any Indebtedness required to be computed on a pro forma basis in accordance with
clause (x) of Section 10.12 hereof and bearing a floating interest rate shall be
computed as if the rate in effect on the date of computation had been the
applicable rate for the entire period, (ii) in making such computation, the
Consolidated Interest Expense attributable to interest on any Indebtedness under
a revolving credit facility required to be computed on a pro forma basis in
accordance with clause (x) of Section 10.12 hereof shall be computed based upon
the average daily balance of such Indebtedness during the applicable period,
provided that such average daily balance shall be reduced by the amount of any
repayment of Indebtedness under a revolving credit facility during the
applicable period, which repayment permanently reduced the commitments or
amounts available to be reborrowed under such facility, (iii) notwithstanding
clauses (i) and (ii) of this proviso, interest on Indebtedness determined on a
fluctuating basis, to the extent such interest is covered by agreements relating
to Interest Rate Protection Obligations, shall be deemed to have accrued at the
rate per annum resulting after giving effect to the operation of such agreements
and (iv) in making such calculation, Consolidated Interest Expense shall exclude
interest attributable to Dollar-Denominated Production Payments.

     "Consolidated Income Tax Expense" means, for any period, the provision for
federal, state, local and foreign income taxes of the Company and its Restricted
Subsidiaries for such period as determined on a consolidated basis in accordance
with GAAP.

     "Consolidated Interest Expense" means, for any period, without duplication,
the sum of (i) the interest expense of the Company and its Restricted
Subsidiaries for such period as determined on a consolidated basis in accordance
with GAAP, including, without limitation, (a) any amortization of debt discount,
(b) the net cost under Interest Rate Protection Obligations (including any
amortization of discounts), (c) the interest portion of any deferred payment
obligation, (d) all

                                       8
<PAGE>
 
commissions, discounts and other fees and charges owed with respect to letters
of credit and bankers' acceptance financing and (e) all accrued interest, in
each case to the extent attributable to such period, (ii) to the extent any
Indebtedness of any Person (other than the Company or a Restricted Subsidiary)
is guaranteed by the Company or any Restricted Subsidiary, the aggregate amount
of interest paid or accrued by such other Person during such period attributable
to any such Indebtedness, in each case to the extent attributable to that
period, (iii) the aggregate amount of the interest component of Capitalized
Lease Obligations paid, accrued and/or scheduled to be paid or accrued by the
Company and its Restricted Subsidiaries during such period as determined on a
consolidated basis in accordance with GAAP and (iv) the aggregate amount of
dividends paid or accrued on Redeemable Capital Stock or Preferred Stock of the
Company and its Restricted Subsidiaries, to the extent such Redeemable Capital
Stock or Preferred Stock is owned by Persons other than Restricted Subsidiaries,
less (v) to the extent included in clauses (i), (ii) or (iii), writeoff of
capitalized debt issuance costs of the Company and its Restricted Subsidiaries
during such period.

     "Consolidated Net Income" means, for any period, the consolidated net
income (or loss) of the Company and its Restricted Subsidiaries for such period
as determined in accordance with GAAP, adjusted by excluding (a) net after-tax
extraordinary gains or losses (less all fees and expenses relating thereto), (b)
net after-tax gains or losses (less all fees and expenses relating thereto)
attributable to Asset Sales, (c) the net income (or net loss) of any Person
(other than the Company or any of its Restricted Subsidiaries), in which the
Company or any of its Restricted Subsidiaries has an ownership interest, except
to the extent of the amount of dividends or other distributions or interest on
indebtedness actually paid to the Company or its Restricted Subsidiaries in cash
by such other Person during such period (regardless of whether such cash
dividends, distributions or interest on indebtedness is attributable to net
income (or net loss) of such Person during such period or during any prior
period), (d) net income (or net loss) of any Person combined with the Company or
any of its Restricted Subsidiaries on a "pooling of interests" basis
attributable to any period prior to the date of combination, (e) the net income
of any Restricted Subsidiary to the extent that the declaration or payment of
dividends or similar distributions by that Restricted Subsidiary is not at the
date of determination permitted, directly or indirectly, by operation of the
terms of its charter or any agreement, instrument, judgment, decree, order,
statute, rule or governmental regulation applicable to that Restricted
Subsidiary or its stockholders, provided, however, that the net income of a
Foreign Subsidiary subject to restrictions on the payment of dividends or
similar distributions related to project financing Indebtedness incurred in
compliance with Section 10.12 hereof shall not be excluded to the extent of the
sum of, without duplication, (i) the aggregate amount of all principal and
interest on such project financing Indebtedness, plus (ii) capital expenditures;
provided further, however, that the net income of a Foreign Subsidiary subject
to restrictions on the payment of dividends or similar distributions shall not
be excluded to the extent that such restrictions relate to completion of the
project being financed by such project financing Indebtedness and such
restriction is in effect for a period of no more than 18 months from the time of
incurrence of such project financing Indebtedness, (f) any writedowns of non-
current assets, provided, however, that any ceiling limitation writedowns under
SEC guidelines shall be treated as capitalized costs, as if such writedowns had
not occurred, and (g) any expenses associated with the merger between the

                                       9
<PAGE>
 
Company and United Meridian Corporation occurring prior to December 31, 1998 and
not in excess of $40 million in the aggregate.

     "Consolidated Net Worth" means, at any date, the consolidated stockholders'
equity of the Company less the amount of such stockholders' equity attributable
to Redeemable Capital Stock or treasury stock of the Company and its Restricted
Subsidiaries, as determined in accordance with GAAP.

     "Consolidated Non-cash Charges" means, for any period, the aggregate
depreciation, depletion, amortization and other non-cash expenses of the Company
and its Restricted Subsidiaries reducing Consolidated Net Income for such
period, determined on a consolidated basis in accordance with GAAP (excluding
any such non-cash charge which requires an accrual of or reserve for cash
charges for any future period).

     "Corporate Trust Office" means the corporate trust office of the Trustee,
at which at any particular time its corporate trust business shall be
administered, which office at the date of execution of this Indenture is located
at 950 17th Street, Suite 650, Denver, Colorado 80202, Attention: Corporate
Trust Department, except that with respect to presentation of Securities for
payment or for registration of transfer or exchange, such term shall mean the
office or agency of the Trustee at which, at any particular time, its corporate
agency business shall be conducted.

     "Credit Agreement" means the Amended and Restated Credit Agreement dated as
of July 8, 1998 among the Company, as borrower, OEI Louisiana, as guarantor, and
Chase Bank of Texas, National Association, as agent, the other agents parties
thereto, and the lenders parties thereto, as such agreement may be amended,
modified, supplemented, extended, restated, replaced (including replacement
after the termination of such agreement), restructured, increased, renewed or
refinanced from time to time in one or more credit agreements, loan agreements,
instruments or similar agreements, with the same or different agents or lenders,
as such may be further amended, modified, supplemented, extended, restated,
replaced (including replacement after the termination of such agreement),
restructured, increased, renewed or refinanced from time to time, in each case
in accordance with and as permitted by this Indenture.

     "Credit Agreement Obligations" means all monetary obligations of every
nature of the Company or a Restricted Subsidiary, including without limitation,
obligations to pay principal and interest, reimbursement obligations under
letters of credit, fees, expenses and indemnities, from time to time owed to the
lenders or any agent under or in respect of the Credit Agreement.

     "Default" means any event, act or condition that is, or after notice or
passage of time or both would be, an Event of Default.

     "Defaulted Interest" has the meaning specified in Section 3.9 hereof.

                                       10
<PAGE>
 
     "Definitive Securities" means Securities that are in the form set forth in
Section 2.2 hereto (but without including the paragraph referred to in the
footnote in Section 2.2 hereof).

     "Depositary" means with respect to the Securities issuable or issued in
whole or in part in global form, the Person specified in Section 3.5 hereof as
the Depositary with respect to the Securities, until a successor shall have been
appointed and become such pursuant to the applicable provision of this
Indenture, and, thereafter, "Depositary" shall mean or include such successor.

     "Designated Guarantor Senior Indebtedness" means, with respect to a
Subsidiary Guarantor, (i) all Guarantor Senior Indebtedness of such Subsidiary
Guarantor under the Credit Agreement Obligations, (ii) all Guarantor Senior
Indebtedness of such Subsidiary Guarantor under the Senior Note Obligations and
(iii) any other Guarantor Senior Indebtedness which (a) at the time of
incurrence equals or exceeds $10,000,000 in aggregate principal amount and (b)
is specifically designated by such Subsidiary Guarantor in the instrument
evidencing such Guarantor Senior Indebtedness as "Designated Guarantor Senior
Indebtedness" for purposes of this Indenture.

     "Designated Senior Indebtedness" means (i) all Senior Indebtedness under
the Credit Agreement Obligations, (ii) all Senior Indebtedness under the Senior
Note Obligations and (iii) any other Senior Indebtedness which (a) at the time
of incurrence equals or exceeds $10,000,000 in aggregate principal amount and
(b) is specifically designated by the Company in the instrument evidencing such
Senior Indebtedness as "Designated Senior Indebtedness" for purposes of this
Indenture.

     "Disinterested Director" means, with respect to any transaction or series
of transactions in respect of which the Board of Directors of the Company is
required to deliver a Board Resolution hereunder, a member of the Board of
Directors of the Company who does not have any material direct or indirect
financial interest (other than an interest arising solely from the beneficial
ownership of Capital Stock of the Company) in or with respect to such
transaction or series of transactions.

     "Dollar-Denominated Production Payments" means production payment
obligations recorded as liabilities in accordance with GAAP, together with all
undertakings and obligations in connection therewith.

     "Event of Default" has the meaning specified in Section 5.1 hereof.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended from
time to time, and any successor act thereto.

     "Exchange Offer" means the offer by the Company to the Holders of all
outstanding Transfer Restricted Securities to exchange all such outstanding
Transfer Restricted Securities held by such Holders for Series B Securities, in
an aggregate principal amount equal to the aggregate principal amount of the
Transfer Restricted Securities tendered in such exchange offer by such Holders.

                                       11
<PAGE>
 
     "Existing Indentures" means, collectively, the indenture related to the
Company's 10 3/8% Senior Subordinated Notes due 2005, the indenture related to
the Company's 9 3/4% Senior Subordinated Notes due 2006 and the indenture
related to the Company's 8 7/8% Senior Subordinated Notes due 2007, in each case
as amended and supplemented to the date hereof and as such may be further
amended and supplemented from time to time.

     "Existing Notes" means (i) the 10 3/8% Senior Subordinated Notes due 2005
of the Company issued pursuant to the Indenture, dated as of October 30, 1995,
between the Company, as successor by merger to United Meridian Corporation, as
issuer, OEI Louisiana, as successor by merger to UMC Petroleum Corporation, as
subsidiary guarantor, and U.S. Bank Trust National Association, as trustee, as
amended and supplemented by the First and Second Supplemental Indentures
thereto, (ii) the 9 3/4% Senior Subordinated Notes due 2006 of the Company
issued pursuant to the Indenture, dated as of September 26, 1996, between the
Company, as issuer, OEI Louisiana, as subsidiary guarantor, and State Street
Bank and Trust Company, as trustee, as amended and supplemented by the First
Supplemental Indenture thereto, and (iii) the 8 7/8% Senior Subordinated Notes
due 2007 of the Company issued pursuant to the Indenture, dated as of July 2,
1997, between the Company, as issuer, OEI Louisiana, as subsidiary guarantor,
and State Street Bank and Trust Company, as trustee, as amended and supplemented
by the First Supplemental Indenture thereto, in each case as such notes and
indentures may be further amended and supplemented from time to time.

     "Existing Senior Notes" means the 13 1/2% Senior Notes due 2004 of the
Company issued pursuant to the Indenture, dated as of December 1, 1994, between
the Company, as issuer, OEI Louisiana, as subsidiary guarantor, and State Street
Bank and Trust Company, as trustee, as amended and supplemented by the First,
Second and Third Supplemental Indentures thereto, and as further amended and
supplemented from time to time.

     "Fair Market Value" means the fair market value of a Property (including
shares of Capital Stock) or Redeemable Capital Stock as determined by a Board
Resolution of the Company adopted in good faith, which determination shall be
conclusive for purposes of this Indenture; provided however, that unless
otherwise specified herein, the Board of Directors shall be under no obligation
to obtain any valuation or assessment from any investment banker, appraiser or
other third party.

     "Federal Bankruptcy Code" means the United States Bankruptcy Code of 
Title 11 of the United States Code, as amended from time to time.

     "Foreign Subsidiary" means (i) any Restricted Subsidiary engaged in the Oil
and Gas Business exclusively outside the United States of America, irrespective
of its jurisdiction of incorporation, and (ii) any other Restricted Subsidiary
whose assets (excluding any cash and Cash Equivalents) consist exclusively of
Capital Stock or Indebtedness of one or more Restricted Subsidiaries described
in clause (i) of this definition.

                                       12
<PAGE>
 
     "GAAP" means generally accepted accounting principles in the United States
as in effect on the Issue Date.

     "Guarantee" means, as applied to any obligation, (i) a guarantee (other
than by endorsement of negotiable instruments for collection in the ordinary
course of business), direct or indirect, in any manner, of any part or all of
such obligation and (ii) an agreement, direct or indirect, contingent or
otherwise, the practical effect of which is to assure in any way the payment or
performance (or payment of damages in the event of non-performance) of all or
any part of such obligation, including, without limiting the foregoing, the
payment of amounts drawn down by letters of credit. When used as a verb,
"guarantee" shall have a corresponding meaning.

     "Guarantor" means any Restricted Subsidiary that incurs a Subsidiary
Guarantee.

     "Guarantor Senior Indebtedness" means all Indebtedness of a Subsidiary
Guarantor (present and future) created, incurred, assumed or guaranteed by such
Subsidiary Guarantor (and all renewals, substitutions, refinancings or
replacements thereof) (including the principal of, interest on and fees,
premiums, expenses (including costs of collection), indemnities and other
amounts payable in connection with such Indebtedness) (and including, in the
case of the Credit Agreement and any guarantees related to the Senior Notes and
the Existing Senior Notes, interest accruing after the filing of a petition by
or against such Subsidiary Guarantor under any bankruptcy law, in accordance
with and at the rate, including any default rate, specified with respect to such
indebtedness, whether or not a claim for such interest is allowed as a claim
after such filing in any proceeding under such bankruptcy law), unless the
instrument governing such Indebtedness expressly provides that such Indebtedness
is not senior in right of payment to its Subsidiary Guarantee. Notwithstanding
the foregoing, Guarantor Senior Indebtedness of a Subsidiary Guarantor will not
include (i) Indebtedness of such Subsidiary Guarantor evidenced by its
Subsidiary Guarantee, (ii) Indebtedness of such Subsidiary Guarantor that is
expressly subordinate or junior in right of payment to any Guarantor Senior
Indebtedness of such Subsidiary Guarantor or its Subsidiary Guarantee, (iii)
Indebtedness which, when incurred and without respect to any election under
Section 1111(b) of Title 11 United States Code, is by its terms without recourse
to such Subsidiary Guarantor, (iv) any repurchase, redemption or other
obligation in respect of Redeemable Capital Stock of such Subsidiary Guarantor,
(v) to the extent it might constitute Indebtedness, any liability for federal,
state, local or other taxes owed or owing by such Subsidiary Guarantor, (vi)
Indebtedness of such Subsidiary Guarantor to the Company or any of the Company's
other Subsidiaries or any other Affiliate of the Company or any of such
Affiliate's Subsidiaries, and (vii) that portion of any Indebtedness of such
Subsidiary Guarantor which at the time of issuance is issued in violation of
this Indenture (but, as to any such Indebtedness, no such violation shall be
deemed to exist for purposes of this clause (vii) if the holder(s) of such
Indebtedness or their representative or such Subsidiary Guarantor shall have
furnished to the Trustee an opinion of counsel unqualified in all material
respects of independent legal counsel, addressed to the Trustee (which legal
counsel may, as to matters of fact, rely upon a certificate of such Subsidiary
Guarantor) to the effect that the incurrence of such Indebtedness does not
violate the provisions of this Indenture); provided that the foregoing
exclusions shall not affect the priorities of any Indebtedness arising solely by
operation of law in any case or proceeding or

                                       13
<PAGE>
 
similar event described in clause (a), (b) or (c) of the definition of
"Insolvency or Liquidation Proceeding" included herein.

     "Holder" means a Person in whose name a Security is registered in the
Security Register.

     "Indebtedness" means, with respect to any Person, without duplication, (a)
all liabilities of such Person for borrowed money or for the deferred purchase
price of Property or services, excluding any trade accounts payable and other
accrued current liabilities incurred in the ordinary course of business, but
including, without limitation, all obligations, contingent or otherwise, of such
Person in connection with any letters of credit, bankers' acceptance or other
similar credit transaction and in connection with any agreement to purchase,
redeem, exchange, convert or otherwise acquire for value any Capital Stock of
such Person, or any warrants, rights or options to acquire such Capital Stock,
now or hereafter outstanding, if, and to the extent, any of the foregoing would
appear as a liability upon a balance sheet of such Person prepared in accordance
with GAAP, (b) all obligations of such Person evidenced by bonds, notes,
debentures or other similar instruments, if, and to the extent, any of the
foregoing would appear as a liability upon a balance sheet of such Person
prepared in accordance with GAAP, (c) all Indebtedness of such Person created or
arising under any conditional sale or other title retention agreement with
respect to Property acquired by such Person (even if the rights and remedies of
the seller or lender under such agreement in the event of default are limited to
repossession or sale of such Property), but excluding trade accounts payable
arising in the ordinary course of business, (d) all Capitalized Lease
Obligations of such Person, (e) the Attributable Indebtedness (in excess of any
related Capitalized Lease Obligations) related to any Sale/Leaseback Transaction
of such Person, (f) all Indebtedness referred to in the preceding clauses of
other Persons and all dividends of other Persons, the payment of which is
secured by (or for which the holder of such Indebtedness has an existing right,
contingent or otherwise, to be secured by) any Lien upon Property (including,
without limitation, accounts and contract rights) owned by such Person, even
though such Person has not assumed or become liable for the payment of such
Indebtedness (the amount of such obligation being deemed to be the lesser of the
value of such Property or asset or the amount of the obligation so secured), (g)
all guarantees by such Person of Indebtedness referred to in this definition
(including, with respect to any Production Payment, any warranties or guaranties
of production or payment by such Person with respect to such Production Payment
but excluding other contractual obligations of such Person with respect to such
Production Payment), (h) all Redeemable Capital Stock of such Person valued at
the greater of its voluntary or involuntary maximum fixed repurchase price plus
accrued dividends, (i) all obligations of such Person under or in respect of
currency exchange contracts and Interest Rate Protection Obligations and (j) any
amendment, supplement, modification, deferral, renewal, extension or refunding
of any liability of such Person of the types referred to in clauses (a) through
(i) above. For purposes hereof, the "maximum fixed repurchase price" of any
Redeemable Capital Stock which does not have a fixed repurchase price shall be
calculated in accordance with the terms of such Redeemable Capital Stock as if
such Redeemable Capital Stock were purchased on any date on which Indebtedness
shall be required to be determined pursuant to this Indenture, and if such price
is based upon, or measured by, the Fair Market Value of such Redeemable Capital
Stock, such Fair Market Value shall be determined in good faith by the board of
directors of the issuer of such Redeemable Capital Stock,

                                       14
<PAGE>
 
provided, however, that if such Redeemable Capital Stock is not at the date of
determination permitted or required to be repurchased, the "maximum fixed
repurchase price" shall be the book value of such Redeemable Capital Stock.
Subject to clause (g) of the first sentence of this definition, neither Dollar-
Denominated Production Payments nor Volumetric Production Payments shall be
deemed to be Indebtedness.

     "Indenture" means this instrument as originally executed and as it may from
time to time be supplemented or amended by one or more indentures supplemental
hereto entered into pursuant to the applicable provisions hereof.

     "Initial Purchasers" means Merrill Lynch, Pierce, Fenner & Smith
Incorporated, Chase Securities Inc., J.P. Morgan Securities Inc., Lehman
Brothers Inc. and Salomon Brothers Inc as initial purchasers in the Offering.

     "Insolvency or Liquidation Proceeding" means, with respect to any Person,
(a) an insolvency or bankruptcy case or proceeding, or any receivership,
liquidation, reorganization or other similar case or proceeding, relative to
such Person or to its creditors, as such, or its assets, or (b) any liquidation,
dissolution or other winding-up of such Person, whether voluntary or involuntary
and whether or not involving insolvency or bankruptcy, or (c) any general
assignment for the benefit of creditors or any other marshaling of assets and
liabilities of such Person.

     "Interest Payment Date" means the Stated Maturity of an installment of
interest on the Securities.

     "Interest Rate Protection Obligations" means the obligations of any Person
pursuant to any arrangement with any other Person whereby, directly or
indirectly, such Person is entitled to receive from time to time periodic
payments calculated by applying either a floating or a fixed rate of interest on
a stated notional amount in exchange for periodic payments made by such Person
calculated by applying a fixed or a floating rate of interest on the same
notional amount and shall include, without limitation, interest rate swaps,
caps, floors, collars and similar agreements or arrangements designed to protect
against or manage such Person's and any of its Subsidiaries' exposure to
fluctuations in interest rates.

     "Investment" means, with respect to any Person, any direct or indirect
advance, loan, guarantee of Indebtedness or other extension of credit or capital
contribution to (by means of any transfer of cash or other Property or assets to
others or any payment for Property, assets or services for the account or use of
others), or any purchase or acquisition by such Person of any Capital Stock,
bonds, notes, debentures or other securities (including derivatives) or
evidences of Indebtedness issued by, any other Person. In addition, the Fair
Market Value of the net assets of any Restricted Subsidiary at the time that
such Restricted Subsidiary is designated an Unrestricted Subsidiary shall be
deemed to be an "Investment" made by the Company in such Unrestricted Subsidiary
at such time. "Investments" shall exclude (a) extensions of trade credit on
commercially reasonable terms in accordance with normal trade practices, (b)
Interest Rate Protection Obligations entered into in

                                       15
<PAGE>
 
the ordinary course of business or as required by any Permitted Indebtedness or
any Indebtedness incurred in compliance with Section 10.12 hereof, but only to
the extent that the notional principal amount of such Interest Rate Protection
Obligations does not exceed 105% of the principal amount of such Indebtedness to
which such Interest Rate Protection Obligations relate and (c) Capital Stock,
bonds, notes, debentures or other securities received as a result of Asset Sales
permitted under Section 10.17 hereof.

     "Issue Date" means the closing date for the sale and original issuance of
the Securities to the Initial Purchasers.

     "Lien" means any mortgage, charge, pledge, lien (statutory or other),
security interest, hypothecation, assignment for security, claim, or preference
or priority or other encumbrance or similar agreement or preferential
arrangement of any kind or nature whatsoever (including, without limitation, any
agreement to give or grant a Lien or any lease, conditional sale or other title
retention agreement having substantially the same economic effect as any of the
foregoing) upon or with respect to any Property of any kind. A Person shall be
deemed to own subject to a Lien any Property which such Person has acquired or
holds subject to the interest of a vendor or lessor under any conditional sale
agreement, capital lease or other title retention agreement.

     "Make-Whole Premium" means, in connection with any optional redemption of
any Security prior to the Five-Year Date, the excess, if any, of (i) the
aggregate present value as of the date of such redemption of each dollar of
principal of such Security being redeemed and the amount of interest (exclusive
of interest accrued to the date of redemption) and premium that would have been
payable in respect of such dollar if such redemption had been made on the Five-
Year Date, determined by discounting, on a semiannual basis, such principal,
interest and premium at a rate equal to the sum of the Treasury Yield
(determined on the business day immediately preceding the date of such
redemption) plus 0.45% per annum, from the respective dates on which such
principal, interest and premium would have been payable if such redemption had
been made on the Five-Year Date, over (ii) the aggregate principal amount of
such Securities being redeemed.

     "Material Change" means an increase or decrease (excluding changes that
result solely from changes in prices) of more than 50% during a fiscal quarter
in the estimated discounted future net cash flows from proved oil and gas
reserves of the Company and its Restricted Subsidiaries, calculated in
accordance with clause (a) (i) of the definition of Adjusted Consolidated Net
Tangible Assets; provided, however, that the following will be excluded from the
calculation of Material Change: (i) any acquisitions during the quarter of oil
and gas reserves that have been estimated by a nationally recognized firm of
independent petroleum engineers and on which a report or reports exist and (ii)
any disposition of Properties existing at the beginning of such quarter that
have been disposed of as provided in Section 10.17 hereof.

     "Maturity" means, with respect to any Security, the date on which any
principal of such Security becomes due and payable as therein or herein
provided, whether at the Stated Maturity with

                                       16
<PAGE>
 
respect to such principal or by declaration of acceleration, call for redemption
or purchase or otherwise.

     "Moody's" means Moody's Investors Service, Inc. and its successors.

     "Net Cash Proceeds" means, with respect to any Asset Sale, the proceeds
thereof in the form of cash or Cash Equivalents including payments in respect of
deferred payment obligations when received in the form of cash or Cash
Equivalents (except to the extent that such obligations are financed or sold
with recourse to the Company or any Restricted Subsidiary), net of (i) brokerage
commissions and other fees and expenses (including fees and expenses of legal
counsel and investment banks) related to such Asset Sale, (ii) provisions for
all taxes payable as a result of such Asset Sale, (iii) amounts required to be
paid to any Person (other than the Company or any Restricted Subsidiary) owning
a beneficial interest in the assets subject to the Asset Sale and (iv)
appropriate amounts to be provided by the Company or any Restricted Subsidiary,
as the case may be, as a reserve required in accordance with GAAP consistently
applied against any liabilities associated with such Asset Sale and retained by
the Company or any Restricted Subsidiary, as the case may be, after such Asset
Sale, including, without limitation, pension and other post-employment benefit
liabilities, liabilities related to environmental matters and liabilities under
any indemnification obligations associated with such Asset Sale, all as
reflected in an Officers' Certificate delivered to the Trustee; provided,
however, that any amounts remaining after adjustments, revaluations or
liquidations of such reserves shall constitute Net Cash Proceeds.

     "Net Working Capital" means (i) all current assets of the Company and its
Restricted Subsidiaries, minus (ii) all current liabilities of the Company and
its Restricted Subsidiaries, except current liabilities included in
Indebtedness, in each case as set forth in financial statements of the Company
prepared in accordance with GAAP.

     "Non-payment Default" means, for purposes of Article XIV hereof, any event
(other than a Payment Default) the occurrence of which entitles one or more
Persons to act to accelerate the maturity of any Designated Senior Indebtedness.

     "Non-recourse Indebtedness" means Indebtedness or that portion of
Indebtedness of the Company incurred in connection with the acquisition by the
Company of any Property or assets and as to which (a) the holders of such
Indebtedness agree that they will look solely to the Property or assets so
acquired and securing such Indebtedness for payment on or in respect of such
Indebtedness and (b) no default with respect to such Indebtedness would permit
(after notice or passage of time or both), according to the terms thereof, any
holder of any Indebtedness of the Company or a Restricted Subsidiary to declare
a default on such Indebtedness or cause the payment thereof to be accelerated or
payable prior to its stated maturity.

     "North American Restricted Subsidiary" means any Restricted Subsidiary at
least 90% of the Adjusted Consolidated Net Tangible Assets of which are located
onshore (or in water not deeper than 15 feet) in the United States or Canada (as
evaluated immediately prior to the designation of

                                       17
<PAGE>
 
such Subsidiary to be an Unrestricted Subsidiary); and "North American
Unrestricted Subsidiary" means such Subsidiary after such designation.

     "Obligations" means any principal of, premium, if any, and interest on, and
any other amounts (including, without limitation, any payment obligations with
respect to the Securities as a result of any Asset Sale, Change of Control or
redemption) owing in respect of, the Securities payable pursuant to the terms of
the Securities or this Indenture or upon acceleration of the Securities.

     "OEI Louisiana" means Ocean Energy, Inc., a Louisiana corporation and
wholly-owned subsidiary of the Company.

     "Offering" means the Offering of the Series A Securities pursuant to the
Offering Memorandum.

     "Offering Memorandum" means the Offering Memorandum of the Company, dated
July 1, 1998, relating to the Offering.

     "Officer" means, with respect to any Person, the Chairman of the Board, the
President, any Vice President, the Chief Financial Officer, the Treasurer, an
Assistant Treasurer, the Secretary or an Assistant Secretary of such Person.

     "Officers' Certificate" means a certificate signed by the Chairman, the
President or a Vice President, and by the Treasurer, an Assistant Treasurer, the
Secretary or an Assistant Secretary of the Company, and delivered to the
Trustee.

     "Oil and Gas Business" means (i) the acquisition, exploration, development,
operation and disposition of interests in oil, gas and other hydrocarbon
Properties, (ii) the gathering, marketing, treating, processing, storage,
refining, selling and transporting of any production from such interests or
Properties, (iii) any business relating to or arising from exploration for or
development, production, treatment, processing, storage, refining,
transportation or marketing of oil, gas and other minerals and products produced
in association therewith, (iv) any power generation and electrical transmission
business in a jurisdiction outside of North America where fuel required by such
business is supplied, directly or indirectly, from production reserves
substantially from blocks in which the Company or its Restricted Subsidiaries
participate and (v) any activity necessary, appropriate or incidental to the
activities described in the foregoing clauses (i) through (iv) of this
definition.

     "Opinion of Counsel" means a written opinion of counsel, who may be counsel
for the Company (or any Subsidiary Guarantor, if applicable), including an
employee of the Company (or any Subsidiary Guarantor, if applicable), and who
shall be reasonably acceptable to the Trustee.

                                       18
<PAGE>
 
     "Outstanding," when used with respect to Securities, means, as of the date
of determination, all Securities theretofore authenticated and delivered under
this Indenture, except:

          (i) Securities theretofore canceled by the Trustee or delivered to the
     Trustee for cancellation;

          (ii) Securities, or portions thereof, for whose payment or redemption
     money in the necessary amount has been theretofore deposited with the
     Trustee or any Paying Agent (other than the Company) in trust or set aside
     and segregated in trust by the Company (if the Company shall act as its own
     Paying Agent) for the Holders of such Securities; provided that, if such
     Securities are to be redeemed, notice of such redemption has been duly
     given pursuant to this Indenture or provision therefor satisfactory to the
     Trustee has been made;

          (iii)  Securities, except to the extent provided in Sections 12.2 and
     12.3 hereof, with respect to which the Company has effected legal
     defeasance and/or covenant defeasance as provided in Article XII hereof;
     and

          (iv)   Securities which have been paid pursuant to Section 3.8 hereof
     or in exchange for or in lieu of which other Securities have been
     authenticated and delivered pursuant to this Indenture, other than any such
     Securities in respect of which there shall have been presented to the
     Trustee proof satisfactory to it that such Securities are held by a bona
     fide purchaser in whose hands the Securities are valid obligations of the
     Company;

provided, however, that in determining whether the Holders of the requisite
principal amount of Outstanding Securities have given any request, demand,
authorization, direction, consent, notice or waiver hereunder, and for the
purpose of making the calculations required by TIA Section 313, Securities owned
by the Company, any Subsidiary Guarantor, or any other obligor upon the
Securities or any Affiliate of the Company, any Subsidiary Guarantor, or such
other obligor shall be disregarded and deemed not to be Outstanding, except
that, in determining whether the Trustee shall be protected in making such
calculation or in relying upon any such request, demand, authorization,
direction, consent, notice or waiver, only Securities which the Trustee knows to
be so owned shall be so disregarded.  Securities so owned which have been
pledged in good faith may be regarded as Outstanding if the pledgee establishes
to the satisfaction of the Trustee the pledgee's right so to act with respect to
such Securities and that the pledgee is not the Company, any Subsidiary
Guarantor, or any other obligor upon the Securities or any Affiliate of the
Company, any Subsidiary Guarantor, or such other obligor.

     "Pari Passu Indebtedness" means any Indebtedness of the Company that is
pari passu in right of payment to the Securities.

     "Paying Agent" means any Person (including the Company acting as Paying
Agent) authorized by the Company to pay the principal of (and premium, if any,
on) or interest on any Securities on behalf of the Company.

                                       19
<PAGE>
 
     "Payment Default" means any default in the payment when due (whether at
Stated Maturity, upon scheduled repayment, upon acceleration or otherwise) of
principal of or premium, if any, or interest on, or of unreimbursed amounts
under drawn letters of credit or fees relating to letters of credit
constituting, any Designated Senior Indebtedness.

     "Permitted Guarantor Junior Securities" means with respect to any
Subsidiary Guarantor, so long as the effect of any exclusion employing this
definition is not to cause such Subsidiary Guarantee to be treated in any case
or proceeding or similar event described in clause (a), (b) or (c) of the
definition of Insolvency or Liquidation Proceeding as part of the same class of
claims as Guarantor Senior Indebtedness of such Subsidiary Guarantor or any
class of claims pari passu with, or senior to, Guarantor Senior Indebtedness of
such Subsidiary Guarantor, for any payment or distribution, debt or equity
securities of such Subsidiary Guarantor or any successor Person provided for or
by a plan of reorganization or readjustment that are subordinated at least to
the same extent that such Subsidiary Guarantee is subordinated to the payment of
all Guarantor Senior Indebtedness of such Subsidiary Guarantor when outstanding;
provided that (i) if a new Person results from such reorganization or
readjustment, such Person assumes any Guarantor Senior Indebtedness of such
Subsidiary Guarantor not paid in full in cash or Cash Equivalents in connection
with such reorganization or readjustment and (ii) the rights of the holders of
such Guarantor Senior Indebtedness are not, without the consent of such holders,
altered by such reorganization or readjustment.

     "Permitted Indebtedness" means any of the following:

          (i)    Indebtedness of the Company under one or more bank credit or
     revolving credit facilities in an aggregate principal amount at any one
     time outstanding not to exceed the greater of (A) $500 million and (B) an
     amount equal to the sum of (x) $350 million and (y) 25% of Adjusted
     Consolidated Net Tangible Assets determined as of the date of the
     incurrence of such Indebtedness (such greater amount being referred to as
     the "Adjusted Maximum Credit Amount") (plus interest and fees under such
     facilities), less any amounts derived from Asset Sales and applied to the
     required permanent reduction of Senior Indebtedness (and a permanent
     reduction of the related commitment to lend or amount available to be
     reborrowed in the case of a revolving credit facility) under such credit
     facilities as contemplated by Section 10.17(b) hereof (the "Maximum Credit
     Amount") (with the Maximum Credit Amount to be an aggregate maximum amount
     for the Company and all Restricted Subsidiaries, pursuant to clause (i) of
     the definition of "Permitted Subsidiary Indebtedness"), and any renewals,
     amendments, extensions, supplements, modifications, deferrals, refinancings
     or replacements (each, for purposes of this clause, a "refinancing")
     thereof by the Company, including any successive refinancings thereof by
     the Company, so long as the aggregate principal amount of any such new
     Indebtedness, together with the aggregate principal amount of all other
     Indebtedness outstanding pursuant to this clause (i) (and clause (i) of the
     definition of "Permitted Subsidiary Indebtedness"), shall not at any one
     time exceed the Maximum Credit Amount;

                                       20
<PAGE>
 
          (ii)   Indebtedness of the Company under the Senior Notes and the
     Securities;

          (iii)  Indebtedness of the Company outstanding on the Issue Date;

          (iv)   obligations of the Company pursuant to Interest Rate Protection
     Obligations, but only to the extent such obligations do not exceed 105% of
     the aggregate principal amount of the Indebtedness covered by such Interest
     Rate Protection Obligations; obligations under currency exchange contracts
     entered into in the ordinary course of business; and hedging arrangements
     that the Company enters into in the ordinary course of business for the
     purpose of protecting the production of the Company and its Restricted
     Subsidiaries against fluctuations in oil or natural gas prices;

          (v)    Indebtedness of the Company to any Restricted Subsidiaries;

          (vi)   in-kind obligations relating to net gas balancing positions
     arising in the ordinary course of business and consistent with past
     practice;

          (vii)  Indebtedness in respect of bid, performance or surety bonds
     issued for the account of the Company or any Restricted Subsidiary in the
     ordinary course of business (including obligations of the type described in
     clause (g) of the definition of the term "Permitted Liens"), including
     guarantees and letters of credit supporting such bid, performance, surety
     or other obligations (in each case other than for an obligation for money
     borrowed);

          (viii) any renewals, extensions, substitutions, refinancings or
     replacements (each, for purposes of this clause, a "refinancing") by the
     Company of any Indebtedness of the Company other than Indebtedness incurred
     pursuant to clauses (iv), (v), (vi) and (vii) of this definition, including
     any successive refinancings by the Company, so long as (A) any such new
     Indebtedness shall be in a principal amount that does not exceed the
     principal amount (or, if such Indebtedness being refinanced provides for an
     amount less than the principal amount thereof to be due and payable upon a
     declaration of acceleration thereof, such lesser amount as of the date of
     determination) so refinanced plus the amount of any premium required to be
     paid in connection with such refinancing pursuant to the terms of the
     Indebtedness refinanced or the amount of any premium reasonably determined
     by the Company as necessary to accomplish such refinancing, plus the amount
     of expenses of the Company incurred in connection with such refinancing,
     (B) in the case of any refinancing of Subordinated Indebtedness, such new
     Indebtedness is made subordinate to the Securities at least to the same
     extent as the Indebtedness being refinanced and (C) such new Indebtedness
     has an Average Life equal to or longer than the Average Life of the
     Indebtedness being refinanced and a final Stated Maturity equal to or later
     than the final Stated Maturity of the Indebtedness being refinanced;

          (ix)   Non-recourse Indebtedness;

                                       21
<PAGE>
 
          (x)    Indebtedness arising from agreements of the Company or a
     Restricted Subsidiary providing for indemnification, adjustment of purchase
     price or similar obligations, in each case, incurred or assumed in
     connection with the disposition of any business, assets or a Subsidiary,
     other than guarantees of Indebtedness incurred by any Person acquiring all
     or any portion of such business, assets or a Subsidiary for the purpose of
     financing such acquisition;

          (xi)   Indebtedness of the Company to an Unrestricted Subsidiary for
     money borrowed, provided that such Indebtedness is subordinated in right of
     payment to the Securities and the Stated Maturity of such Indebtedness is
     later than the final Stated Maturity of the Securities;

          (xii)  any guarantee of Guarantor Senior Indebtedness or Indebtedness
     of a Foreign Subsidiary incurred in compliance with Section 10.12 hereof;
     and

          (xiii) other Indebtedness of the Company and the Restricted
     Subsidiaries that are Subsidiary Guarantors in an aggregate principal
     amount not in excess of $50,000,000 at any one time outstanding.

     "Permitted Investments" means any of the following: (i) Investments in Cash
Equivalents; (ii) Investments in the Company or any of its Restricted
Subsidiaries; (iii) Investments in an amount not to exceed 5% of Adjusted
Consolidated Net Tangible Assets at any one time outstanding; (iv) Investments
by the Company or any of its Restricted Subsidiaries in another Person, if as a
result of such Investment (A) such other Person becomes a Restricted Subsidiary
of the Company; or (B) such other Person is merged or consolidated with or into,
or transfers or conveys all or substantially all of its assets to, the Company
or a Restricted Subsidiary; (v) entry into operating agreements, joint ventures,
partnership agreements (whether general or limited), limited liability company
agreements, subscription agreements, stock purchase agreements, stockholder
agreements, working interests, royalty interests, mineral leases, processing
agreements, farm-out agreements, contracts for the sale, transportation or
exchange of oil and natural gas, unitization agreements, pooling arrangements,
area of mutual interest agreements, production sharing agreements and other
similar or customary agreements, transactions, properties, interests or
arrangements, and Investments and expenditures in connection therewith or
pursuant thereto, in each case made or entered into in the ordinary course of
the Oil and Gas Business; (vi) shares of Capital Stock or other securities
received in settlement of debts owed to the Company or any of its Restricted
Subsidiaries as a result of foreclosure, perfection or enforcement of any Lien
or indebtedness or in connection with any good faith settlement or a bankruptcy
proceeding; (vii) entry into any hedging arrangements in the ordinary course of
business for the purpose of protecting the Company's or any Restricted
Subsidiary's production against fluctuations in oil or natural gas prices;
(viii) entry into any currency exchange contract in the ordinary course of
business; (ix) Investments in any Person engaged in the power generation and
electrical transmission business where fuel required by such business is
supplied, directly or indirectly, from production reserves substantially from
blocks in which the Company or its Restricted Subsidiaries participate, provided
that the aggregate amount of

                                       22
<PAGE>
 
Investments outstanding at any one time in such Person shall be no more than
$15,000,000; (x) Investments in any Person that is the purchaser of a portion of
the interests of a Foreign Subsidiary, provided that such Investments are in the
nature of a note or other deferred payment obligation to the Company or such
Foreign Subsidiary and are in an amount of no more than $35,000,000 at any one
time outstanding; (xi) workers' compensation, utility, lease and similar
deposits and prepaid expenses in the ordinary course of business; (xii)
endorsements of negotiable instruments and documents in the ordinary course of
business; or (xiii) designation of a North American Restricted Subsidiary to be
an Unrestricted Subsidiary if the credit ratings assigned to the Securities by
each of S&P and Moody's, respectively, immediately after giving effect to such
designation (the "post-designation credit ratings") are or will be greater than
or equal to the greater of (A) the credit rating assigned to the Securities by
such Rating Agency immediately prior to giving effect to such designation and
(B) such credit rating as of the Issue Date. For purposes of determining
compliance with clause (xiii) of the preceding sentence, (1) subsequent changes
in such credit rating unrelated to such designation shall not cause such
designation to fail to constitute a "Permitted Investment," and (2) without
limitation of other forms of proof of the post-designation credit rating
assigned to the Securities, any press release issued by such Rating Agency or
any written notification from such Rating Agency to the Company addressing the
impact of such designation on the credit rating assigned to the Securities
(whether such press release or written notification is issued before,
contemporaneously with or after such designation) shall constitute conclusive
evidence of the post-designation credit rating.

     "Permitted Junior Securities" means, so long as the effect of any exclusion
employing this definition is not to cause the Securities to be treated in any
case or proceeding or similar event described in clause (a), (b) or (c) of the
definition of Insolvency or Liquidation Proceeding as part of the same class of
claims as Senior Indebtedness or any class of claims pari passu with, or senior
to, Senior Indebtedness, for any payment or distribution, debt or equity
securities of the Company or any successor Person provided for or by a plan of
reorganization or readjustment that are subordinated at least to the same extent
that the Securities are subordinated to the payment of all Senior Indebtedness
when outstanding; provided that (i) if a new Person results from such
reorganization or readjustment, such Person assumes any Senior Indebtedness not
paid in full in cash or Cash Equivalents in connection with such reorganization
or readjustment and (ii) the rights of the holders of such Senior Indebtedness
are not, without the consent of such holders, altered by such reorganization or
readjustment.

     "Permitted Liens" means the following types of Liens:

          (a)  Liens existing as of the Issue Date;

          (b)  Liens securing the Securities;

          (c)  Liens in favor of the Company or a Restricted Subsidiary that is
     a Subsidiary Guarantor;

                                       23
<PAGE>
 
          (d)  Liens securing Senior Indebtedness, Guarantor Senior Indebtedness
     or Indebtedness of a Restricted Subsidiary incurred in compliance with
     Section 10.12 hereof;

          (e)  Liens for taxes, assessments and governmental charges or claims
     either (i) not delinquent or (ii) contested in good faith by appropriate
     proceedings and as to which the Company or its Restricted Subsidiaries
     shall have set aside on its books such reserves as may be required pursuant
     to GAAP;

          (f)  statutory Liens of landlords and Liens of carriers, warehousemen,
     mechanics, suppliers, materialmen, repairmen and other Liens imposed by law
     incurred in the ordinary course of business for sums not delinquent or
     being contested in good faith, if such reserve or other appropriate
     provision, if any, as shall be required by GAAP shall have been made in
     respect thereof;

          (g)  Liens incurred or deposits made in the ordinary course of
     business in connection with workers' compensation, unemployment insurance
     and other types of social security, or to secure the payment or performance
     of tenders, statutory or regulatory obligations, surety and appeal bonds,
     bids, leases, government contracts and leases, performance and return of
     money bonds and other similar obligations, including letters of credit and
     bank guarantees required or requested by the United States, any State
     thereof or any foreign government or any subdivision, department, agency,
     organization or instrumentality of any of the foregoing in connection with
     any contract or statute (exclusive of obligations for the payment of
     borrowed money but including lessee or operator obligations under statutes,
     governmental regulations, contracts or instruments related to the
     ownership, exploration and production of oil, gas and minerals on state,
     Federal or foreign lands or waters);

          (h)  judgment Liens not giving rise to an Event of Default so long as
     any appropriate legal proceedings which may have been duly initiated for
     the review of such judgment shall not have been finally terminated or the
     period within which such proceeding may be initiated shall not have
     expired;

          (i)  easements, rights-of-way, restrictions and other similar charges
     or encumbrances not interfering in any material respect with the ordinary
     conduct of the business of the Company or any of its Restricted
     Subsidiaries;

          (j)  any interest or title of a lessor under any Capitalized Lease
     Obligation or operating lease;

          (k)  Liens resulting from the deposit of funds or evidences of
     Indebtedness in trust for the purpose of defeasing Indebtedness of the
     Company or any of the Subsidiaries;

                                       24
<PAGE>
 
          (l)  Liens securing obligations under hedging agreements that the
     Company or any Restricted Subsidiary enters into in the ordinary course of
     business for the purpose of protecting their production against
     fluctuations in oil or natural gas prices, and Liens securing obligations
     under any foreign currency exchange agreement, option or futures contract
     or other similar agreement or arrangement entered into in the ordinary
     course of business and designed to protect against or manage the Company's
     or any of its Restricted Subsidiaries' exposure to fluctuation in foreign
     currency rates;

          (m)  Liens upon specific items of inventory or other goods and
     proceeds of any Person securing such Person's obligations in respect of
     bankers' acceptances issued or created for the account of such Person to
     facilitate the purchase, shipment or storage of such inventory or other
     goods;

          (n)  Liens securing reimbursement obligations with respect to
     commercial letters of credit which encumber documents and other Property
     relating to such letters of credit and products and proceeds thereof;

          (o)  Liens encumbering Property or assets under construction arising
     from progress or partial payments by a customer of the Company or its
     Restricted Subsidiaries relating to such Property or assets;

          (p) Liens encumbering deposits made to secure obligations arising from
     statutory, regulatory, contractual or warranty requirements of the Company
     or any of its Restricted Subsidiaries, including rights of offset and set-
     off;

          (q) Liens securing Interest Rate Protection Obligations which Interest
     Rate Protection Obligations relate to Indebtedness that is secured by Liens
     otherwise permitted under this Indenture;

          (r)  Liens on, or related to, Properties or assets to secure all or
     part of the costs incurred in the ordinary course of business for the
     exploration, drilling, development or operation thereof;

          (s)  Liens on pipeline or pipeline facilities which arise out of
     operation of law;

          (t)  Liens arising under operating agreements, joint venture
     agreements, partnership agreements, oil and gas leases, farm-out
     agreements, division orders, contracts for the sale, transportation or
     exchange of oil and natural gas, unitization and pooling declarations and
     agreements, area of mutual interest agreements and other agreements which
     are customary in the Oil and Gas Business;

          (u)  Liens reserved in oil and gas mineral leases for bonus or rental
     payments and for compliance with the terms of such leases;

                                       25
<PAGE>
 
          (v)  Liens constituting survey exceptions, encumbrances, easements, or
     reservations of, or rights to others for, rights-of-way, zoning or other
     restrictions as to the use of real properties, and minor defects of title
     which, in the case of any of the foregoing, were not incurred or created to
     secure the payment of borrowed money or the deferred purchase price of
     Property or services, and in the aggregate do not materially adversely
     affect the value of Property of the Company and the Restricted
     Subsidiaries, taken as a whole, or materially impair the use of such
     Properties for the purposes for which such Properties are held by the
     Company or any Restricted Subsidiaries;

          (w)  Liens securing Non-recourse Indebtedness; provided, however, that
     the related Non-recourse Indebtedness shall not be secured by any Property
     or assets of the Company or any Restricted Subsidiary other than the
     Property and assets acquired by the Company with the proceeds of such Non-
     recourse Indebtedness, all improvements, additions and accessions thereto
     and all proceeds thereof;

          (x)  purchase money Liens; provided, however, that (i) the related
     purchase money Indebtedness shall not be secured by any Property of the
     Company or any Restricted Subsidiary other than the Property so acquired,
     all improvements, additions and accessions thereto and all proceeds thereof
     and (ii) the Lien securing such Indebtedness shall be created within 90
     days of such acquisition; and

          (y)  Liens securing Acquired Indebtedness, provided that any such Lien
     extends only to the Properties that were subject to such Lien prior to the
     related acquisition by the Company or such Restricted Subsidiary, all
     improvements, additions and accessions thereto and all proceeds thereof,
     and was not created, incurred or assumed in contemplation of such
     transaction;

Notwithstanding anything in clauses (a) through (y) of this definition, the term
"Permitted Liens" does not include any Liens resulting from the creation,
incurrence, issuance, assumption or guarantee of any Production Payments other
than Production Payments that are created, incurred, issued, assumed or
guaranteed in connection with the financing of, and within 30 days after, the
acquisition of the Properties or assets that are subject thereto.

     "Permitted Subsidiary Indebtedness" means any of the following:

          (i)    Indebtedness of any Restricted Subsidiary under one or more
     bank credit or revolving credit facilities (and "refinancings" thereof) in
     an amount at any one time outstanding not to exceed the Maximum Credit
     Amount (in the aggregate for all Restricted Subsidiaries and the Company,
     pursuant to clause (i) of the definition of "Permitted Indebtedness");

          (ii)   Indebtedness of any Restricted Subsidiary outstanding on the
     Issue Date;

                                       26
<PAGE>
 
          (iii)  obligations of any Restricted Subsidiary pursuant to Interest
     Rate Protection Obligations, but only to the extent such obligations do not
     exceed 105% of the aggregate principal amount of the Indebtedness covered
     by such Interest Rate Protection Obligations; obligations under currency
     exchange contracts entered into in the ordinary course of business; and
     hedging arrangements that any Restricted Subsidiary enters into in the
     ordinary course of business for the purpose of protecting the production of
     the Company and its Restricted Subsidiaries against fluctuations in oil or
     natural gas prices;

          (iv)   the Subsidiary Guarantees, the Senior Guarantees and the
     Guarantees of the Existing Senior Notes and the Existing Notes (and any
     assumption of the obligations guaranteed thereby);

          (v)    Indebtedness of any Restricted Subsidiary relating to
     guarantees by such Restricted Subsidiary of Permitted Indebtedness pursuant
     to clause (i) of the definition of "Permitted Indebtedness";

          (vi)   in-kind obligations relating to net gas balancing positions
     arising in the ordinary course of business and consistent with past
     practice;

          (vii)  Indebtedness in respect of bid, performance or surety bonds
     issued for the account of any Restricted Subsidiary in the ordinary course
     of business (including obligations of the type described in clause (g) of
     the definition of the term "Permitted Liens"), including guarantees and
     letters of credit supporting such bid, performance, surety or other
     obligations (in each case other than for an obligation for money borrowed);

          (viii) Indebtedness of any Restricted Subsidiary to any other
     Restricted Subsidiary or to the Company;

          (ix)   Indebtedness relating to guarantees by any Restricted
     Subsidiary permitted to be incurred pursuant to Section 10.13 hereof;

          (x)    any guarantee of Guarantor Senior Indebtedness or Indebtedness
     of a Foreign Subsidiary incurred in compliance with Section 10.12 hereof;

          (xi)   Indebtedness of any Restricted Subsidiary permitted under
     clauses (vi), (vii), (x) or (xiii) of the definition of "Permitted
     Indebtedness"; and

          (xii)  any renewals, extensions, substitutions, refinancings or
     replacements (each, for purposes of this clause, a "refinancing") by any
     Restricted Subsidiary of any Indebtedness of such Restricted Subsidiary,
     including any successive refinancings by such Restricted Subsidiary, so
     long as (x) any such new Indebtedness shall be in a principal amount that
     does not exceed the principal amount (or, if such Indebtedness being
     refinanced provides for an amount less than the principal amount thereof to
     be due and payable upon

                                       27
<PAGE>
 
     a declaration of acceleration thereof, such lesser amount as of the date of
     determination) so refinanced plus the amount of any premium required to be
     paid in connection with such refinancing pursuant to the terms of the
     Indebtedness refinanced or the amount of any premium reasonably determined
     by such Restricted Subsidiary as necessary to accomplish such refinancing,
     plus the amount of expenses of such Subsidiary incurred in connection with
     such refinancing and (y) such new Indebtedness has an Average Life equal to
     or longer than the Average Life of the Indebtedness being refinanced and a
     final Stated Maturity equal to or later than the final Stated Maturity of
     the Indebtedness being refinanced.

     "Person" means any individual, corporation, limited liability company,
partnership, joint venture, association, joint stock company, trust,
unincorporated organization or government or any agency or political subdivision
thereof.

     "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and, for the purposes of this definition, any Security
authenticated and delivered under Section 3.8 hereof in exchange for a mutilated
Security or in lieu of a lost, destroyed or stolen Security shall be deemed to
evidence the same debt as the mutilated, lost, destroyed or stolen Security.

     "Preferred Stock" means, with respect to any Person, any and all shares,
interests, participations or other equivalents (however designated) of such
Person's preferred or preference stock, whether outstanding on or issued after
the Issue Date, including, without limitation, all classes and series of
preferred or preference stock of such Person.

     "Production Payments" means, collectively, Dollar-Denominated Production
Payments and Volumetric Production Payments.

     "Property" means, with respect to any Person, any interest of such Person
in any kind of property or asset, whether real, personal or mixed, or tangible
or intangible, including, without limitation, Capital Stock in any other Person.

     "Public Equity Offering" means an underwritten public offering for cash by
the Company of its Qualified Capital Stock pursuant to a registration statement
that has been declared effective by the Commission (other than a registration
statement on Form S-8 or any successor form or otherwise relating to equity
securities issuable under any employee benefit plan of the Company).

     "Qualified Capital Stock" of any Person means any and all Capital Stock of
such Person other than Redeemable Capital Stock.

     "Redeemable Capital Stock" means any class or series of Capital Stock that,
either by its terms, by the terms of any security into which it is convertible
or exchangeable or by contract or otherwise, is, or upon the happening of an
event or passage of time would be, required to be redeemed prior to the final
Stated Maturity of the Securities or is redeemable at the option of the

                                       28
<PAGE>
 
holder thereof at any time prior to such final Stated Maturity, or is
convertible into or exchangeable for debt securities at any time prior to such
final Stated Maturity.

     "Redemption Date," when used with respect to any Security to be redeemed,
in whole or in part, means the date fixed for such redemption by or pursuant to
this Indenture.

     "Redemption Price," when used with respect to any Security to be redeemed,
means the price at which it is to be redeemed pursuant to this Indenture.

     "Registrable Securities" shall have the meaning assigned to such term in
the Registration Rights Agreement.

     "Registration Rights Agreement" means that certain Registration Rights
Agreement dated as of July 8, 1998, among the Company and the Initial
Purchasers.

     "Regular Record Date" for the interest payable on any Interest Payment Date
means the December 15 or June 15 (whether or not a Business Day), as the case
may be, next preceding such Interest Payment Date.

     "Responsible Officer," when used with respect to the Trustee, means any
officer in the Corporate Trust Administration Department of the Trustee, and
also means, with respect to a particular corporate trust matter, any other
officer to whom such matter is referred because of his knowledge of and
familiarity with the particular subject.

     "Restricted Subsidiary" means any Subsidiary of the Company, whether
existing on or after the Issue Date, unless such Subsidiary of the Company is an
Unrestricted Subsidiary or is designated as an Unrestricted Subsidiary pursuant
to the terms of this Indenture.

     "Rule 144A" means Rule 144A under the Securities Act.

     "S&P" means Standard and Poor's Ratings Group and its successors.

     "Sale/Leaseback Transaction" means, with respect to any Person, any direct
or indirect arrangement pursuant to which Properties or assets are sold or
transferred by such Person or a Subsidiary of such Person and are thereafter
leased back from the purchaser or transferee thereof by such Person or one of
its Subsidiaries.

     "Securities" has the meaning stated in the first recital of this Indenture
and more particularly means any Securities authenticated and delivered under
this Indenture.

     "Securities Act" means the Securities of 1933, as amended, or any successor
statute.

                                       29
<PAGE>
 
     "Security Custodian" means the Trustee, as custodian with respect to the
Global Securities, or any successor entity thereto.

     "Security Register" and "Security Registrar" have the respective meanings
specified in Section 3.5 hereof.

     "Senior Guarantees" means any guarantee of the Senior Notes by any
Restricted Subsidiary.

     "Senior Indebtedness" means the principal of, premium, if any, and interest
on any Indebtedness of the Company (including, in the case of the Credit
Agreement, the Senior Notes and the Existing Senior Notes, interest accruing
after the filing of a petition by or against the Company under any bankruptcy
law, in accordance with and at the rate, including any default rate, specified
with respect to such indebtedness, whether or not a claim for such interest is
allowed as a claim after such filing in any proceeding under such bankruptcy
law), whether outstanding on the Issue Date or thereafter created, incurred or
assumed, unless, in the case of any particular Indebtedness, the instrument
creating or evidencing the same or pursuant to which the same is outstanding
expressly provides that such Indebtedness shall not be senior in right of
payment to the Securities. Without limiting the generality of the foregoing,
"Senior Indebtedness" shall also include the Senior Note Obligations.
Notwithstanding the foregoing, "Senior Indebtedness" shall not include (a)
Indebtedness evidenced by the Securities, (b) Indebtedness that is expressly
subordinate or junior in right of payment to any Senior Indebtedness of the
Company, (c) Indebtedness which, when incurred and without respect to any
election under Section 1111 (b) of Title 11 United States Code, is by its terms
without recourse to the Company, (d) any repurchase, redemption or other
obligation in respect of Redeemable Capital Stock of the Company, (e) to the
extent it might constitute Indebtedness, any liability for federal, state, local
or other taxes owed or owing by the Company, (f) Indebtedness of the Company to
a Subsidiary of the Company or any other Affiliate of the Company or any of such
Affiliate's Subsidiaries, and (g) that portion of any Indebtedness of the
Company which at the time of issuance is issued in violation of this Indenture
(but, as to any such Indebtedness, no such violation shall be deemed to exist
for purposes of this clause (g) if the holder(s) of such Indebtedness or their
representative or the Company shall have furnished to the Trustee an opinion of
counsel unqualified in all material respects of independent legal counsel,
addressed to the Trustee (which legal counsel may, as to matters of fact, rely
upon a certificate of the Company) to the effect that the incurrence of such
Indebtedness does not violate the provisions of this Indenture); provided that
the foregoing exclusions shall not affect the priorities of any Indebtedness
arising solely by operation of law in any case or proceeding or similar event
described in clause (a), (b) or (c) of the definition of Insolvency or
Liquidation Proceeding included herein.

     "Senior Notes" means (i) the 7 5/8% Senior Notes due 2005 of the Company
issued pursuant to the Indenture, dated as of July 8, 1998, between the Company,
as issuer, OEI Louisiana, as subsidiary guarantor, and Norwest Bank Minnesota,
National Association, as trustee, as amended and supplemented from time to time,
and (ii) the 8 1/4% Senior Notes due 2018 of the Company issued pursuant to the
Indenture, dated as of July 8, 1998, between the Company, as issuer, OEI

                                       30
<PAGE>
 
Louisiana, as subsidiary guarantor, and Norwest Bank Minnesota, National
Association, as trustee, as amended and supplemented from time to time.

     "Senior Note Obligations" means all monetary obligations of every nature of
the Company or a Restricted Subsidiary, including without limitation,
obligations to pay principal and interest, fees, expenses and indemnities, from
time to time owed to the holders or the trustee in respect of the Senior Notes
and the Existing Senior Notes.

     "Senior Representative" means the Bank Agent or any other representatives
designated in writing to the Trustee of the holders of any class or issue of
Designated Senior Indebtedness; provided that, in the absence of a
representative of the type described above, any holder or holders of a majority
of the principal amount outstanding of any class or issue of Designated Senior
Indebtedness may collectively act as Senior Representative for such class or
issue, subject to the provisions of any agreements relating to such Designated
Senior Indebtedness.

     "Series A Securities" means the Company's 8 3/8% Series A Senior Notes due
2008 to be issued pursuant to this Indenture.

     "Series B Securities" means the Company's 8 3/8% Series B Senior Notes due
2008 to be issued pursuant to this Indenture in the Exchange Offer.

     "Significant Subsidiary" means any Restricted Subsidiary the consolidated
assets of which comprise in excess of 5% of Adjusted Consolidated Net Tangible
Assets (as shown in the most recent audited consolidated balance sheet of the
Company and its Subsidiaries).

     "Special Record Date" for the payment of any Defaulted Interest means a
date fixed by the Trustee pursuant to Section 3.9 hereof.

     "Stated Maturity" means, when used with respect to any Security or any
installment of interest thereon, the date specified in such Security as the
fixed date on which the principal of such Security or such installment of
interest is due and payable, and, when used with respect to any other
Indebtedness or any installment of interest thereon, means the date specified in
the instrument evidencing or governing such Indebtedness as the fixed date on
which the principal of such Indebtedness or such installment of interest is due
and payable.

     "Subordinated Indebtedness" means Indebtedness of the Company which is
expressly subordinated in right of payment to the Securities.

     "Subsidiary" means, with respect to any Person, (i) a corporation a
majority of whose Voting Stock is at the time, directly or indirectly, owned by
such Person, by one or more Subsidiaries of such Person or by such Person and
one or more Subsidiaries thereof or (ii) any other Person (other than a
corporation), including, without limitation, a joint venture, in which such
Person, one or more Subsidiaries thereof or such Person and one or more
Subsidiaries thereof, directly or indirectly, at

                                       31
<PAGE>
 
the date of determination thereof, has at least majority ownership interest
entitled to vote in the election of directors, managers or trustees thereof (or
other Persons performing similar functions).

     "Subsidiary Guarantee" has the meaning specified in Section 13.1 hereof.

     "Subsidiary Guarantor" means (i) OEI Louisiana, (ii) each of the Company's
Restricted Subsidiaries that becomes a guarantor of the Securities in compliance
with the provisions of Section 10.13 or Article XIII hereof and (iii) each of
the Company's Subsidiaries executing a supplemental indenture in which such
Subsidiary agrees to be bound by the terms of this Indenture and to guarantee on
an unsubordinated basis the payment of the Securities pursuant to the provisions
of Article XIII hereof.

     "Transfer Restricted Securities" means the Registrable Securities under the
Registration Rights Agreement.

     "Treasury Yield" means, in connection with the calculation of any Make-
Whole Premium on any Security, the yield to maturity at the time of computation
of United States Treasury securities with a constant maturity (as compiled by
and published in the most recent Federal Reserve Statistical Release H.15 (519)
that has become publicly available at least two business days prior to the date
fixed for redemption (or, if such Statistical Release is no longer published,
any publicly available source of similar data)) equal to the then remaining
period of time until the Five-Year Date; provided that if no United States
Treasury security is available with such a constant maturity and for which a
closing yield is given, the Treasury Yield shall be obtained by linear
interpolation (calculated to the nearest one-twelfth of a year) from the closing
yields of United States Treasury securities for which such yields are given,
except that if the remaining period of time until the Five-Year Date is less
than one year, the weekly average yield on actually traded United States
Treasury securities adjusted to a constant maturity of one year shall be used.

     "Trust Indenture Act" or "TIA" means the Trust Indenture Act of 1939, as
amended and in force at the Issue Date, except as provided in Section 9.5
hereof.

     "Trustee" means the Person named as the "Trustee" in the first paragraph of
this Indenture until a successor Trustee shall have become such pursuant to the
applicable provisions of this Indenture, and thereafter "Trustee" shall mean
such successor Trustee.

     "Unrestricted Subsidiary" means (i) Havre Pipeline Company, LLC and Lion
GPL, S.A., (ii) any Subsidiary of the Company that at the time of determination
will be designated an Unrestricted Subsidiary by the Board of Directors of the
Company as provided below and (iii) any Subsidiary of an Unrestricted
Subsidiary, in each case until such time as such Subsidiary is designated as a
Restricted Subsidiary for purposes of this Indenture. The Board of Directors of
the Company may designate any Subsidiary of the Company as an Unrestricted
Subsidiary so long as (a) neither the Company nor any Restricted Subsidiary is
directly or indirectly liable pursuant to the terms of any Indebtedness of such
Subsidiary; (b) no default with respect to any Indebtedness of

                                       32
<PAGE>
 
such Subsidiary would permit (upon notice, lapse of time or otherwise) any
holder of any other Indebtedness of the Company or any Restricted Subsidiary to
declare a default on such other Indebtedness or cause the payment thereof to be
accelerated or payable prior to its stated maturity; (c) neither the Company nor
any Restricted Subsidiary has made an Investment in such Subsidiary unless such
Investment was made pursuant to, and in accordance with Section 10.11 hereof,
(including as a Permitted Investment thereunder); and (d) such designation shall
not result in the creation or imposition of any Lien on any of the Properties of
the Company or any Restricted Subsidiary (other than any Permitted Lien or any
Lien the creation or imposition of which shall have been in compliance with
Section 10.15 hereof); provided, however, that with respect to clause (a), the
Company or a Restricted Subsidiary may be liable for Indebtedness of an
Unrestricted Subsidiary if (x) such liability constituted a Permitted Investment
or a Restricted Payment permitted by Section 10.11 hereof, in each case at the
time of incurrence, or (y) the liability would be a Permitted Investment at the
time of designation of such Subsidiary as an Unrestricted Subsidiary. Any such
designation by the Board of Directors of the Company shall be evidenced to the
Trustee by filing a Board Resolution with the Trustee giving effect to such
designation. Any such designation shall be deemed to be an Investment, as more
particularly described in the definition of such term, above. The Board of
Directors of the Company may designate any Unrestricted Subsidiary as a
Restricted Subsidiary if, immediately after giving effect to such designation,
(i) no Default or Event of Default shall have occurred and be continuing, (ii)
the Company could incur $1.00 of additional Indebtedness (not including the
incurrence of Permitted Indebtedness) under Section 10.12 hereof, and (iii) if
any of the Properties of the Company or any of its Restricted Subsidiaries would
upon such designation become subject to any Lien (other than a Permitted Lien),
the creation or imposition of such Lien shall have been in compliance with
Section 10.15 hereof.

     "Vice President," when used with respect to the Company or the Trustee,
means any vice president, whether or not designated by a number or a word or
words added before or after the title "vice president."

     "Volumetric Production Payments" means production payment obligations
recorded as deferred revenue in accordance with GAAP, together with all
undertakings and obligations in connection therewith.

     "Voting Stock" means any class or classes of Capital Stock pursuant to
which the holders thereof have the general voting power under ordinary
circumstances to elect at least a majority of the board of directors, managers
or trustees of any Person (irrespective of whether or not, at the time, stock of
any other class or classes shall have, or might have, voting power by reason of
the happening of any contingency).

     "Wholly Owned Restricted Subsidiary" means any Restricted Subsidiary to the
extent (i) all of the Capital Stock or other ownership interests in such
Restricted Subsidiary, other than any directors qualifying shares mandated by
applicable law, is owned directly or indirectly by the Company or (ii) such
Restricted Subsidiary is organized in a foreign jurisdiction and is required by
the applicable laws and regulations of such foreign jurisdiction to be partially
owned by the

                                       33
<PAGE>
 
government of such foreign jurisdiction or individual or corporate citizens of
such foreign jurisdiction in order for such Restricted Subsidiary to transact
business in such foreign jurisdiction, provided that the Company, directly or
indirectly, owns the remaining Capital Stock or ownership interest in such
Restricted Subsidiary and, by contract or otherwise, controls the management and
business of such Restricted Subsidiary and derives the economic benefits of
ownership of such Restricted Subsidiary to substantially the same extent as if
such Restricted Subsidiary were a wholly owned Subsidiary.

     Section  1.2   Other Definitions.
 
                                                   Defined
     Term                                         in Section
     ----                                         ----------
 
     "Agent Members"...........................    3.7
     "Change of Control Notice"................   10.16(c)
     "Change of Control Offer".................   10.16(a)
     "Change of Control Purchase Date".........   10.16(a)
     "Change of Control Purchase Price"........   10.16(a)
     "Defaulted Interest"......................    3.9
     "Five-Year Date"..........................   11.1
     "Global Security".........................    2.1
     "Funding Guarantor".......................   13.5
     "Excess Proceeds".........................   10.17(b)
     "Investment Grade Ratings"................   10.22
     "Net Proceeds Deficiency".................   10.17(c)
     "Net Proceeds Offer"......................   10.17(c)
     "Net Proceeds Payment Date"...............   10.17(c)
     "Offered Price"...........................   10.17(c)
     "Pari Passu Indebtedness Amount"..........   10.17(c)
     "Pari Passu Offer"........................   10.17(c)
     "Payment Amount"..........................   10.17(c)
     "Payment Blockage Notice".................   14.3(b)
     "Payment Blockage Period".................   14.3(b)
     "Physical Securities".....................    2.1
     "Purchase Notice".........................   10.17
     "Rating Agencies".........................   10.22
     "Restricted Payment"......................   10.11(a)
     "SEC".....................................   1.1 ("Commission")
     "Subsidiary Guarantor Non-payment Default"   13.9(b)
     "Subsidiary Guarantor Payment Default"....   13.9(a)
     "Subsidiary Guarantor Payment Notice".....   13.9(b)
     "Surviving Entity"........................    8.1
     "Suspended Covenants".....................   10.22
     "Trigger Date"............................   10.17
     "U.S. Government Obligations".............   12.4(a)

                                       34
<PAGE>
 
          Section  1.3   Incorporation by Reference of Trust Indenture Act.
Whenever this Indenture refers to a provision of the TIA, the provision is
incorporated by reference in and made a part of this Indenture.  The following
TIA terms used in this Indenture have the following meanings:

     "indenture securities" means the Securities,

     "indenture security holder" means a Holder,

     "indenture to be qualified" means this Indenture,

     "indenture trustee" or "institutional trustee" means the Trustee, and

     "obligor" on the indenture securities means the Company or any other
obligor on the Securities.

          All other TIA terms used in this Indenture that are defined by the
TIA, defined by TIA reference to another statute or defined by Commission rule
and not otherwise defined herein have the meanings assigned to them therein.

          Section  1.4   Rules of Construction.  For all purposes of this
Indenture, except as otherwise expressly provided or unless the context
otherwise requires:

          (a) The terms defined in this Article have the meanings assigned to
them in this Article, and include the plural as well as the singular;

          (b) all accounting terms not otherwise defined herein have the
meanings assigned to them in accordance with GAAP;

          (c) the words "herein," "hereof" and "hereunder" and other words of
similar import refer to this Indenture as a whole and not to any particular
Article, Section or other subdivision;

          (d) unless the context otherwise requires, the word "or" is not
exclusive;

          (e) provisions apply to successive events and transactions; and

          (f) references to agreements and other instruments include subsequent
amendments and waivers but only to the extent not prohibited by this Indenture.

                                       35
<PAGE>
 
                                  ARTICLE II

                                SECURITY FORMS
                                --------------

          Section  2.1   Forms Generally.  The Definitive Securities shall be
printed, lithographed or engraved on steel-engraved borders or may be produced
in any other manner, all as determined by the officers executing such Securities
or notations of Subsidiary Guarantees, as the case may be, as evidenced by their
execution of such Securities or notations of Subsidiary Guarantees, as the case
may be.

          Securities (including the notations thereon relating to the Subsidiary
Guarantees and the Trustee's certificate of authentication) bought and sold in
reliance on Rule 144A shall be issued initially in the form of one or more
permanent global Securities substantially in the form set forth in Sections 2.2
through 2.5 hereof (the "Global Security") deposited with the Trustee, as
custodian for the Depositary, duly executed by the Company and authenticated by
the Trustee as hereinafter provided.  Subject to the limitation set forth in
Section 3.1, the principal amount of the Global Securities may be increased or
decreased from time to time by adjustments made on the records of the Trustee as
custodian for the Depositary, as hereinafter provided.

          Securities (including the notations thereon relating to the Subsidiary
Guarantees and the Trustee's certificate of authentication) offered and sold
other than as described in the preceding paragraph shall be issued in the form
of permanent certificated Securities in registered form in substantially the
form set forth in Sections 2.2 through 2.5 hereto ("Physical Securities").

          The Securities, the notations thereon relating to the Subsidiary
Guarantees and the Trustee's certificate of authentication shall be in
substantially the forms set forth in this Article, with such appropriate
insertions, omissions, substitutions and other variations as are required or
permitted by this Indenture, and may have such letters, numbers or other marks
of identification and such legends or endorsements placed thereon as may be
required to comply with the rules of any securities exchange or as may,
consistently herewith, be determined by the officers executing such Securities
or notations of Subsidiary Guarantees, as the case may be, as evidenced by their
execution of the Securities or notations of Subsidiary Guarantees, as the case
may be.  Any portion of the text of any Security may be set forth on the reverse
thereof, with an appropriate reference thereto on the face of the Security.  In
addition to the requirements of Section 2.3, the Securities may also have set
forth on the reverse side thereof a form of assignment and forms to elect
purchase by the Company pursuant to Sections 10.16 and 10.17 hereof.

          Section  2.2   Form of Face of Security.

                              OCEAN ENERGY, INC.

                8 3/8% Series [A/B] Senior Subordinated Note due 2008

     No.                                                             $_________

                                       36
<PAGE>
 
                                                  CUSIP No. [Series A: ________]
                                                            [Series B: ________]

          Ocean Energy, Inc., a Delaware corporation (herein called the
"Company," which term includes any successor Person under the Indenture
hereinafter referred to), for value received, hereby promises to pay to
____________________ or registered assigns the principal sum of ______ Dollars
on July 1, 2008, at the office or agency of the Company referred to below, and
to pay interest thereon, commencing on January 1, 1999 and continuing
semiannually thereafter, on January 1 and July 1 in each year, from July 8,
1998, or from the most recent Interest Payment Date to which interest has been
paid or duly provided for, at the rate of 8 3/8% per annum, until the principal
hereof is paid or duly provided for, and (to the extent lawful) to pay on demand
interest on any overdue interest at the rate borne by the Securities from the
date on which such overdue interest becomes payable to the date payment of such
interest has been made or duly provided for.  The interest so payable, and
punctually paid or duly provided for, on any Interest Payment Date will, as
provided in such Indenture, be paid to the Person in whose name this Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest, which shall be the December 15 or
June 15 (whether or not a Business Day), as the case may be, next preceding such
Interest Payment Date, or, in the case of interest payable at the Maturity of
the principal of the Securities, to the Person to whom principal is paid.  Any
such interest not so punctually paid or duly provided for shall forthwith cease
to be payable to the Holder on such Regular Record Date, and such defaulted
interest, and (to the extent lawful) interest on such defaulted interest at the
rate borne by the Securities, may be paid to the Person in whose name this
Security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice whereof shall be given to Holders of Securities
not less than 10 days prior to such Special Record Date, or may be paid at any
time in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities may be listed, and upon such notice
as may be required by such exchange, all as more fully provided in said
Indenture.

          Payment of the principal of (and premium, if any, on) and interest on
this Security will be made at the office or agency of the Company maintained for
that purpose in The City of New York, or at such other office or agency of the
Company as may be maintained for such purpose, in such coin or currency of the
United States of America as at the time of payment is legal tender for payment
of public and private debts; provided however, that payment of principal,
premium, if any, and interest may be made at the option of the Company (i) by
check mailed to the address of the Person entitled thereto as such address shall
appear on the Security Register or (ii) with respect to Securities held in book-
entry form, by wire transfer to an account maintained by the Holder located in
the United States, as specified in a written notice to the Trustee by any such
Holder requesting payment by wire transfer and specifying the account to which
transfer is requested.

          Unless and until it is exchanged in whole or in part for Securities in
definitive form, this Security may not be transferred except as a whole by the
Depositary to a nominee of the Depositary or by a nominee of the Depositary to
the Depositary or another nominee of the Depositary or by the 

                                       37
<PAGE>
 
Depositary or any such nominee to a successor Depositary or a nominee of such
successor Depositary. The Depository Trust Company shall act as the Depositary
until a successor shall be appointed by the Company and the Registrar. Unless
this certificate is presented by an authorized representative of The Depository
Trust Company (55 Water Street, New York, New York) ("DTC"), to the issuer or
its agent for registration of transfer, exchange or payment, and any certificate
issued is registered in the name of Cede & Co. or such other name as may be
requested by an authorized representative of DTC (and any payment is made to
Cede & Co. or such other entity as may be requested by an authorized
representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch as the registered owner
hereof, Cede & Co., has an interest herein./1/

          THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
1933, AS AMENDED ( THE "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS. NEITHER
THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND ANY
APPLICABLE STATE SECURITIES LAWS.  THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE
HEREOF AGREES (1) NOT TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR
TO (X) THE DATE THAT IS TWO YEARS (OR SUCH SHORTER PERIOD OF TIME AS PERMITTED
BY RULE 144(k) UNDER THE SECURITIES ACT OR ANY SUCCESSOR PROVISION THEREUNDER)
AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF (OR OF ANY PREDECESSOR OF THIS
SECURITY) AND THE LAST DAY ON WHICH OCEAN ENERGY, INC. (THE "COMPANY") OR ANY
AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
THIS SECURITY) AND (Y) SUCH LATER DATE, IF ANY, AS MAY BE REQUIRED BY APPLICABLE
LAWS (THE "RESALE RESTRICTION TERMINATION DATE"), EXCEPT (A) TO THE COMPANY, (B)
PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, (C)
FOR SO LONG AS THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER
THE SECURITIES ACT ("RULE 144A"), TO A PERSON IT REASONABLY BELIEVES IS A
"QUALIFIED INSTITUTIONAL BUYER" AS DEFINED IN RULE 144A THAT IS ACQUIRING SUCH
SECURITY FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL
BUYER TO WHOM NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON
RULE 144A, (D) PURSUANT TO OFFERS AND SALES TO NON-U.S. PERSONS THAT OCCUR
OUTSIDE THE UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE
SECURITIES ACT, OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, AND (2) THAT IT WILL GIVE TO
EACH PERSON TO WHOM THIS SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO 

---------------
/1/ This paragraph should be included only if the Security is issued in global
    form.

                                       38
<PAGE>
 
THE EFFECT OF THIS LEGEND; PROVIDED THAT THE COMPANY, THE TRUSTEE, THE TRANSFER
AGENT AND THE REGISTRAR SHALL HAVE THE RIGHT PRIOR TO ANY SUCH OFFER, SALE OR
TRANSFER (i) PURSUANT TO CLAUSES (D) OR (E) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM, AND (ii) IN EACH OF THE FOREGOING CASES, TO REQUIRE THAT A CERTIFICATE
OF TRANSFER IN THE FORM APPEARING ON THIS SECURITY IS COMPLETED AND DELIVERED BY
THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF A
HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE. THE HOLDER HEREOF, BY
PURCHASING THIS NOTE, REPRESENTS AND AGREES FOR THE BENEFIT OF THE COMPANY THAT
IT IS (1) A QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A OR (2)
A NON-U.S. PERSON AND IS ACQUIRING THE NOTE IN AN "OFFSHORE TRANSACTION"
PURSUANT TO RULE 904 OF REGULATION S UNDER THE SECURITIES ACT. THIS LEGEND WILL
BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE RESTRICTION
TERMINATION DATE. AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION," "UNITED
STATES" AND "U.S. PERSON" HAVE THE MEANING GIVEN TO THEM BY REGULATION S UNDER
THE SECURITIES ACT.

          Reference is hereby made to the further provisions of this Security
set forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

          Unless the certificate of authentication hereon has been duly executed
by the Trustee referred to on the reverse hereof by manual signature, this
Security shall not be entitled to any benefit under the Indenture, or be valid
or obligatory for any purpose.

                                       39
<PAGE>
 
          IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

                                    OCEAN ENERGY, INC.,
                                    a Delaware corporation


                                    By:
                                        -----------------------------------
                                         Chairman of the Board
Attest:


-------------------------------- 
Secretary


          Section  2.3   Form of Reverse of Security.  This Security is one of a
duly authorized issue of securities of the Company designated as its 8 3/8% 
Series [A/B] Senior Subordinated Notes due 2008 (herein called the
"Securities"), limited (except as otherwise provided in the Indenture referred
to below) in aggregate principal amount to $250,000,000, which may be issued
under an indenture (as amended and supplemented from time to time, the
"Indenture") dated as of July 8, 1998, between the Company, the Subsidiary
Guarantors and U.S. Bank Trust National Association, as trustee (herein called
the "Trustee," which term includes any successor trustee under the Indenture),
to which Indenture reference is hereby made for a statement of the respective
rights, limitations of rights, duties, obligations and immunities thereunder of
the Company, the Subsidiary Guarantors, the Trustee and the Holders of the
Securities, and of the terms upon which the Securities are, and are to be,
authenticated and delivered.

          The Indebtedness evidenced by the Securities is, to the extent and in
the manner provided in the Indenture, subordinate and subject in right of
payment to the prior payment in full of all Senior Indebtedness (as defined in
the Indenture) and this Security is issued subject to such provisions. Each
Holder of this Security, by accepting the same, (i) agrees to and shall be bound
by such provisions, (ii) authorizes and directs the Trustee on his behalf to
take such action as may be necessary or appropriate to effectuate the
subordination as provided in the Indenture and (iii) appoints the Trustee as his
attorney-in-fact for such purpose.

          Prior to July 1, 2003, the Securities will be redeemable, in whole but
not in part, at a redemption price equal to the sum of (a) an amount equal to
100% of the principal amount thereof and (b) the Make-Whole Premium, together
with accrued and unpaid interest to the date fixed for redemption. In no event
will such redemption price ever be less than 100% of the principal amount of the
Securities plus accrued interest to the date of redemption. On or after July 1,
2003, the Securities will be redeemable, in whole or in part, at the redemption
prices (expressed as percentages of principal amount) set forth below, plus
accrued and unpaid interest, if any, to the redemption date 

                                       40
<PAGE>
 
(subject to the right of Holders of record on the relevant record date to
receive interest due on an interest payment date that is on or prior to the
redemption date), if redeemed during the 12-month period beginning on July 1 of
the years indicated below:

       Year                      Price
       2003                     104.188%
       2004                     102.792%
       2005                     101.396%
       2006 and thereafter      100.000%

          In addition, at any time and from time to time prior to July 1, 2001,
the Company may, at its option, redeem in the aggregate up to 33 1/3% of the
aggregate principal amount of the Securities originally issued under the
Indenture with the proceeds of one or more Public Equity Offerings by the
Company at a redemption price (expressed as a percentage of principal amount) of
108.375%, plus accrued and unpaid interest, if any, to the date of redemption
(subject to the right of Holders on the relevant record date to receive interest
due on the relevant interest payment date); provided, however, that at least 66
2/3% aggregate principal amount of the Securities must remain outstanding after
each such redemption. In order to effect the foregoing redemption, the Company
must mail notice of redemption no later than 60 days after the related Public
Equity Offering and must consummate such redemption within 90 days of the
closing of the Public Equity Offering.

          In the event that less than all of the Securities are to be redeemed
at any time, selection of such Securities (or any portion thereof that is an
integral multiple of $1,000) for redemption will be made by the Trustee from the
outstanding Securities not previously called for redemption (or otherwise
purchased by the Company) on a pro rata basis, by lot or by such method as the
Trustee shall deem fair and appropriate; provided, however, that no Security
with a principal amount of $1,000 or less shall be redeemed in part.

          Notice of redemption shall be mailed by first-class mail at least 30
but not more than 60 days before the redemption date to each Holder of
Securities to be redeemed at its registered address. If any Security is to be
redeemed in part only, the notice of redemption that relates to such Security
shall state the portion of the principal amount thereof to be redeemed. A new
Security in a principal amount equal to the unredeemed portion thereof will be
issued in the name of the Holder thereof upon cancellation of the original
Security.  On and after the redemption date, interest will cease to accrue on
Securities or portions thereof called for redemption and accepted for payment.

          The Securities do not have the benefit of any sinking fund
obligations.

          In the event of a Change of Control of the Company, and subject to
certain conditions and limitations provided in the Indenture, the Company will
be obligated to make an offer to purchase, on a Business Day not more than 70 or
less than 30 days following the occurrence of a Change of Control of the
Company, all of the then outstanding Securities at a purchase price equal to
101% of 

                                       41
<PAGE>
 
the principal amount thereof, together with accrued and unpaid interest
to the Change of Control Purchase Date, all as provided in the Indenture.

          In the event of Asset Sales, under certain circumstances, the Company
will be obligated to make a Net Proceeds Offer to purchase all or a specified
portion of each Holder's Securities at a purchase price equal to 100% of the
principal amount of the Securities, together with accrued and unpaid interest to
the Net Proceeds Payment Date.

          As set forth in the Indenture, an Event of Default is generally (i)
failure to pay principal of or premium, if any, on any of the Securities upon
maturity, redemption, acceleration or otherwise (including pursuant to a Change
of Control Offer or a Net Proceeds Offer); (ii) default for 30 days in payment
of interest on any of the Securities; (iii) default in the performance of
certain provisions of the Indenture relating to mergers, consolidations and
sales of all or substantially all assets or the failure to make or consummate a
Change of Control Offer or a Net Proceeds Offer; (iv) failure for 30 days after
notice to comply with any other covenants in the Indenture or the Securities;
(v) certain payment defaults under, the acceleration prior to the maturity of,
and the exercise of certain enforcement rights with respect to, certain
Indebtedness of the Company or any Restricted Subsidiary in an aggregate
principal amount in excess of the greater of $20,000,000 and 5% of Adjusted
Consolidated Net Tangible Assets; (vi) the failure of any Subsidiary Guarantee
to be in full force and effect or otherwise to be enforceable (except as
permitted by the Indenture); (vii) certain final judgments against the Company
or any Restricted Subsidiary in an aggregate amount that is more than the
greater of $20,000,000 and 5% of Adjusted Consolidated Net Tangible Assets which
remain unsatisfied and either become subject to commencement of enforcement
proceedings or remain unstayed for a period of 60 days; and (viii) certain
events of bankruptcy, insolvency or reorganization of the Company, any
Subsidiary Guarantor or any Significant Subsidiary.  If any Event of Default
occurs and is continuing, the Trustee or the holders of at least 25% in
aggregate principal amount of the Outstanding Securities may declare the
principal amount of all the Securities to be due and payable immediately, except
that (i) in the case of an Event of Default arising from certain events of
bankruptcy, insolvency or reorganization, the principal amount of the Securities
will become due and payable immediately without further action or notice, and
(ii) in the case of an Event of Default which relates to certain payment
defaults, acceleration or the exercise of certain enforcement rights with
respect to certain Indebtedness, any acceleration of the Securities will be
automatically rescinded if any such Indebtedness is repaid or if the default
relating to such Indebtedness is cured or waived and if the holders thereof have
accelerated such Indebtedness then such holders have rescinded their declaration
of acceleration or if in certain circumstances the proceedings or enforcement
action with respect to the Indebtedness that is the subject of such Event of
Default is terminated or rescinded.  No Holder may pursue any remedy under the
Indenture unless the Trustee shall have failed to act after notice of an Event
of Default and written request by Holders of at least 25% in principal amount of
the Outstanding Securities, and the offer to the Trustee of indemnity reasonably
satisfactory to it; however, such provision does not affect the right to sue for
enforcement of any overdue payment on a Security by the Holder thereof.  Subject
to certain limitations, Holders of a majority in principal amount of the
Outstanding Securities may direct the Trustee in its exercise of any trust or
power.  The Trustee may withhold from Holders notice of any 

                                       42
<PAGE>
 
continuing default (except default in payment of principal, premium or interest)
if it determines in good faith that withholding the notice is in the interest of
the Holders. The Company is required to file quarterly reports with the Trustee
as to the absence or existence of defaults.

          The Indenture contains provisions for defeasance at any time of (i)
the entire indebtedness of the Company on this Security and (ii) certain
restrictive covenants and the related Defaults and Events of Default, upon
compliance by the Company with certain conditions set forth therein, which
provisions apply to this Security.

          The Indenture permits, with certain exceptions as therein provided,
the amendment thereof and the modification of the rights and obligations of the
Company and the Subsidiary Guarantors and the rights of the Holders under the
Indenture at any time by the Company, the Subsidiary Guarantors and the Trustee
with the consent of the Holders of a majority in aggregate principal amount of
the Securities at the time Outstanding.  The Indenture also contains provisions
permitting the Holders of specified percentages in aggregate principal amount of
the Securities at the time Outstanding, on behalf of the Holders of all the
Securities, to waive compliance by the Company with certain provisions of the
Indenture and certain past defaults under the Indenture and their consequences.
Any such consent or waiver by or on behalf of the Holder of this Security shall
be conclusive and binding upon such Holder and upon future Holders of this
Security and of any Security issued upon the registration of transfer hereof or
in exchange herefor or in lieu hereof whether or not notation of such consent or
waiver is made upon this Security.  Without the consent of any Holder, the
Company, the Subsidiary Guarantors and the Trustee may amend or supplement the
Indenture or the Securities to cure any ambiguity, defect or inconsistency, to
provide for uncertificated Securities in addition to or in place of certificated
Securities and to make certain other specified changes and other changes that do
not adversely affect the rights of any Holder in any material respect.

          No reference herein to the Indenture and no provision of this Security
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of (and premium, if any, on)
and interest on this Security at the times, place, and rate, and in the coin or
currency, herein prescribed.

          As provided in the Indenture and subject to certain limitations
therein set forth, the transfer of this Security is registerable on the Security
Register of the Company, upon surrender of this Security for registration of
transfer at the office or agency of the Company maintained for such purpose in
The City of New York, duly endorsed by, or accompanied by a written instrument
of transfer in form satisfactory to the Company and the Security Registrar duly
executed by, the Holder hereof or his attorney duly authorized in writing, and
thereupon one or more new Securities, of authorized denominations and for the
same aggregate principal amount, will be issued to the designated transferee or
transferees.

          The Securities are issuable only in registered form without coupons in
denominations of $1,000 and any integral multiple thereof.  As provided in the
Indenture and subject to certain 

                                       43
<PAGE>
 
limitations therein set forth, the Securities are exchangeable for a like
aggregate principal amount of Securities of a different authorized denomination,
as requested by the Holder surrendering the same.

          No service charge shall be made for any registration of transfer or
exchange of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge payable in connection therewith.

          A director, officer, incorporator, employee, Affiliate or stockholder
of the Company or any Subsidiary Guarantor, as such, shall not have any personal
liability under this Security or the Indenture by reason of his or its status as
such director, officer, incorporator or stockholder.  Each Holder, by accepting
this Security with the notation of Subsidiary Guarantee endorsed hereon, waives
and releases all such liability.  Such waiver and release are part of the
consideration for the issuance of this Security with the notation of Subsidiary
Guarantee endorsed hereon.

          Prior to the time of due presentment of this Security for registration
of transfer, the Company, the Subsidiary Guarantors, the Trustee and any agent
of the Company or the Trustee may treat the Person in whose name this Security
is registered as the owner hereof for all purposes, whether or not this Security
is overdue, and neither the Company, the Subsidiary Guarantors, the Trustee nor
any agent shall be affected by notice to the contrary.

          All terms used in this Security which are defined in the Indenture
shall have the meanings assigned to them in the Indenture.  The Company will
furnish to any Holder upon written request and without charge a copy of the
Indenture.  Requests may be made to the Company at 1201 Louisiana, Suite 1400,
Houston, Texas 77002.

          Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures, the Company has caused CUSIP numbers to be
printed on the Securities as a convenience to the Holders thereof.  No
representation is made as to the accuracy of such numbers as printed on the
Securities and reliance may be placed only on the other identifying information
printed hereon.

          This Security shall be governed by and construed in accordance with
the laws of the State of New York, without regard to conflicts of law
principles.

                                       44
<PAGE>
 
                                 ASSIGNMENT FORM

     To assign this Security, fill in the form below: (I) or (we) assign and
transfer this Security to

                         ------------------------------------------------------
                         (Insert assignee's social security or tax I.D. number)


--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
              (Print or type assignee's name, address and zip code)

   and irrevocably appoint
                           -----------------------------------------------------
   as agent to transfer this Security on the books of the Company.  The agent
may substitute another to act for him.


     Date:                          Your Signature:
           ------------                             ----------------------------
                                           (Sign exactly as your name appears on
                                            the face of this Security)


     Signature Guarantee:
                          ------------------------------------------------------
                              (Participant in a Recognized Signature
                               Guaranty Medallion Program)

                                       45
<PAGE>
 
                    FORM OF OPTION OF HOLDER TO ELECT PURCHASE

          If you want to elect to have this Security purchased by the Company
pursuant to Section 10.16 or Section 10.17 of the Indenture, check the
appropriate box:

                    Section 10.16 [_]    Section 10.17 [_]

          If you want to have only part of this Security purchased by the
Company pursuant to Section 10.16 or Section 10.17 of the Indenture, state the
amount in integral multiples of $1,000:



     Date:                          Signature:
           -------------------                 ---------------------------------
                                       (Sign exactly as your name appears on the
                                        other side of this Security)


     Signature Guarantee:
                          ------------------------------------------------------
                           (Participant in a Recognized Signature
                            Guaranty Medallion Program)

                                       46
<PAGE>
 
                  SCHEDULE OF EXCHANGES OF DEFINITIVE SECURITY*

     The following exchanges of a part of this Global Security for Definitive
Securities have been made:

<TABLE>
<CAPTION>
                                                                   Principal Amount                           
                     Amount of                 Amount of            of this Global          Signature of      
                    decrease in               increase in         Security following    authorized signatory  
  Date of        Principal Amount          Principal Amount          such decrease         of Trustee or      
 Exchange     of this Global Security   of this Global Security      (or increase)       Security Custodian   
------------------------------------------------------------------------------------------------------------
<S>           <C>                       <C>                       <C>                   <C>
 
 
 
 
 
 
 
 
</TABLE> 


---------------
*  This should be included only if the Security is issued in global form.

                                       47
<PAGE>
 
      Section  2.4  Form of Notation Relating to Subsidiary Guarantees.  The
form of notation to be set forth on each Security relating to the Subsidiary
Guarantees shall be in substantially the following form:

                              SUBSIDIARY GUARANTEE

     Subject to the limitations set forth in the Indenture, the Subsidiary
Guarantors (as defined in the Indenture referred to in the Security upon which
this notation is endorsed and each hereinafter referred to as a "Subsidiary
Guarantor," which term includes any successor or additional Subsidiary Guarantor
under the Indenture) have, jointly and severally, unconditionally guaranteed (a)
the due and punctual payment of the principal (and premium, if any) of and
interest on the Securities, whether at maturity, acceleration, redemption or
otherwise, (b) the due and punctual payment of interest on the overdue principal
of and interest on the Securities, if any, to the extent lawful, (c) the due and
punctual performance of all other obligations of the Company to the Holders or
the Trustee, all in accordance with the terms set forth in the Indenture, and
(d) in case of any extension of time of payment or renewal of any Securities or
any of such other obligations, the same will be promptly paid in full when due
or performed in accordance with the terms of the extension or renewal, whether
at Stated Maturity, by acceleration or otherwise.  Capitalized terms used herein
shall have the meanings assigned to them in the Indenture unless otherwise
indicated.

     The obligations of each Subsidiary Guarantor are limited to the maximum
amount as will, after giving effect to all other contingent and fixed
liabilities and after giving effect to any collections from or payments made by
or on behalf of any other Subsidiary Guarantor in respect of the obligations of
such other Subsidiary Guarantor under its Subsidiary Guarantee or pursuant to
its contribution obligations under the Indenture, result in the obligations of
such Subsidiary Guarantor under the Subsidiary Guarantee not constituting a
fraudulent conveyance or fraudulent transfer under federal or state law.  Each
Subsidiary Guarantor that makes a payment or distribution under a Subsidiary
Guarantee shall be entitled to a contribution from each other Subsidiary
Guarantor in a pro rata amount based on the Adjusted Net Assets of each
Subsidiary Guarantor.

     The obligations of the Subsidiary Guarantors to the Holders or the Trustee
pursuant to the Subsidiary Guarantee and the Indenture are expressly subordinate
to all Guarantor Senior Indebtedness to the extent set forth in Article XIII of
the Indenture and reference is made to such Indenture for the precise terms of
such subordination.

     No stockholder, officer, director or incorporator, as such, past, present
or future, of the Subsidiary Guarantors shall have any personal liability under
the Subsidiary Guarantee by reason of his or its status as such stockholder,
officer, director or incorporator.

     Any Subsidiary Guarantor may be released from its Subsidiary Guarantee upon
the terms and subject to the conditions provided in the Indenture.

                                       48
<PAGE>
 
     All terms used in this notation of Subsidiary Guarantee which are defined
in the Indenture referred to in this Security upon which this notation of
Subsidiary Guarantee is endorsed shall have the meanings assigned to them in
such Indenture.

     The Subsidiary Guarantee shall be binding upon each Subsidiary Guarantor
and its successors and assigns and shall inure to the benefit of the Trustee and
the Holders and, in the event of any transfer or assignment of rights by any
Holder or the Trustee, the rights and privileges herein conferred upon that
party shall automatically extend to and be vested in such transferee or
assignee, all subject to the terms and conditions hereof and in the Indenture.

     The Subsidiary Guarantee shall not be valid or obligatory for any purpose
until the certificate of authentication on the Security upon which this
Subsidiary Guarantee is noted shall have been executed by the Trustee under the
Indenture by the manual signature of one of its authorized officers.

                                    OCEAN ENERGY, INC.,
                                    a Louisiana corporation
 


Attest:                             By:
       -------------------              ----------------------------
       Secretary                        President


          Section  2.5  Form of Trustee's Certificate of Authentication.  The
Trustee's certificate of authentication shall be in substantially the following
form:

                    TRUSTEE'S CERTIFICATE OF AUTHENTICATION

          This is one of the 8 3/8% Series [A/B] Senior Subordinated Notes due
2008 referred to in the within-mentioned Indenture.


                              Authenticated:

Dated:
      ------------------
                              U.S. Bank Trust National Association
                              Trustee



                              By:
                                  ---------------------------------------------
                                    Authorized Officer

                                       49
<PAGE>
 
                                  ARTICLE III

                                THE SECURITIES
                                --------------

          Section  3.1  Title and Terms.  The aggregate principal amount of
Securities which may be authenticated and delivered under this Indenture is
limited to $250,000,000 except for Securities authenticated and delivered upon
registration of transfer of, or in exchange for, or in lieu of, other Securities
pursuant to Section 3.4, 3.5, 3.6, 3.8, 9.6, 10.16, 10.17 or 11.8 hereof.

          The Securities shall be known and designated as the "8 3/8% Series A
Senior Subordinated Notes Due 2008" and the "8 3/8% Series B Senior Subordinated
Notes due 2008"of the Company. Their Stated Maturity shall be July 1, 2008, and
they shall bear interest at the rate of 8 3/8% per annum from July 8, 1998, or 
from the most recent Interest Payment Date to which interest has been paid or
duly provided for, payable semiannually on January 1 and July 1 in each year,
commencing January 1, 1999, and at said Stated Maturity, until the principal
thereof is paid or duly provided for.

          The principal of (and premium, if any, on) and interest on the
Securities shall be payable at the office or agency of the Company maintained
for such purpose in The City of New York, or at such other office or agency of
the Company as may be maintained for such purpose pursuant to Section 10.2
hereof; provided, however, that, at the option of the Company, principal,
premium, if any, and interest may be paid (i) by check mailed to addresses of
the Persons entitled thereto as such addresses shall appear on the Security
Register, or (ii) with respect to Securities held in book-entry form, by wire
transfer to an account maintained by the Holder located in the United States, as
specified in a written notice to the Trustee by any such Holder requesting
payment by wire transfer and specifying the account to which transfer is
requested.

          The Securities shall be redeemable as provided in Article XI hereof.

          The Securities shall be subject to defeasance at the option of the
Company as provided in Article XII hereof.

          The Securities shall be guaranteed by the Subsidiary Guarantors as
provided in Article XIII hereof.

          The Securities shall be subordinated in right of payment to Senior
Indebtedness as provided in Article XIV hereof.

          Section  3.2  Denominations.  The Securities shall be issuable only in
registered form without coupons and only in denominations of $1,000 and any
integral multiple thereof.

          Section  3.3  Execution, Authentication, Delivery and Dating.  The
Securities shall be executed on behalf of the Company by its Chairman, its
President or a Vice President of the Company, under its corporate seal
reproduced thereon and attested by its Secretary or an Assistant 

                                       50
<PAGE>
 
Secretary or a Vice President of the Company. The signature of any of these
officers on the Securities may be manual or facsimile signatures of the present
or any future such authorized officer and may be imprinted or otherwise
reproduced on the Securities.

          Securities bearing the manual or facsimile signatures of individuals
who were at any time the proper officers of the Company shall bind the Company,
notwithstanding that such individuals or any of them have ceased to hold such
offices prior to the authentication and delivery of such Securities or did not
hold such offices at the date of such Securities.

          At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities executed by the Company and
having the notation of Subsidiary Guarantees executed by the Subsidiary
Guarantors to the Trustee for authentication, together with a Company Order for
the authentication and delivery of such Securities, and the Trustee in
accordance with such Company Order shall authenticate and deliver such
Securities with the notation of Subsidiary Guarantees thereon as provided in
this Indenture.

          Each Security shall be dated the date of its authentication.

          No Security shall be entitled to any benefit under this Indenture or
be valid or obligatory for any purpose unless there appears on such Security a
certificate of authentication substantially in the form provided for herein duly
executed by the Trustee by manual signature of an authorized officer, and such
certificate upon any Security shall be conclusive evidence, and the only
evidence, that such Security has been duly authenticated and delivered hereunder
and is entitled to the benefits of this Indenture.

          In case the Company, pursuant to and in compliance with Article VIII
hereof, shall be consolidated or merged with or into any other Person or shall
convey, transfer, lease or otherwise dispose of its Properties substantially as
an entirety to any Person, and the successor Person resulting from such
consolidation, or surviving such merger, or into which the Company shall have
been merged, or the Person which shall have received a conveyance, transfer,
lease or other disposition as aforesaid, shall have executed an indenture
supplemental hereto with the Trustee pursuant to Article VIII hereof, any of the
Securities authenticated or delivered prior to such consolidation, merger,
conveyance, transfer, lease or other disposition may, from time to time, at the
request of the successor Person, be exchanged for other Securities executed in
the name of the successor Person with such changes in phraseology and form as
may be appropriate, but otherwise in substance of like tenor as the Securities
surrendered for such exchange and of like principal amount; and the Trustee,
upon Company Request of the successor Person, shall authenticate and deliver
Securities as specified in such request for the purpose of such exchange.  If
Securities shall at any time be authenticated and delivered in any new name of a
successor Person pursuant to this Section in exchange or substitution for or
upon registration of transfer of any Securities, such successor Person, at the
option of the Holders but without expense to them, shall provide for the
exchange of all Securities at the time Outstanding for Securities authenticated
and delivered in such new name.

                                       51
<PAGE>
 
          Section  3.4  Temporary Securities.  Pending the preparation of
Definitive Securities, the Company may execute, and upon Company Order the
Trustee shall authenticate and deliver, temporary Securities which are printed,
lithographed, typewritten, mimeographed or otherwise produced, in any authorized
denomination, substantially of the tenor of the Definitive Securities in lieu of
which they are issued and having the notations of Subsidiary Guarantees thereon
and with such appropriate insertions, omissions, substitutions and other
variations as the officers executing such Securities and notations of Subsidiary
Guarantees may determine, as conclusively evidenced by their execution of such
Securities and notations of Subsidiary Guarantees.

          If temporary Securities are issued, the Company will cause Definitive
Securities to be prepared without unreasonable delay.  After the preparation of
Definitive Securities, the temporary Securities shall be exchangeable for
Definitive Securities upon surrender of the temporary Securities at the office
or agency of the Company designated for such purpose pursuant to Section 10.2
hereof, without charge to the Holder.  Upon surrender for cancellation of any
one or more temporary Securities, the Company shall execute and the Trustee
shall authenticate and deliver in exchange therefor a like principal amount of
Definitive Securities of authorized denominations having notations of Subsidiary
Guarantees thereon.  Until so exchanged, the temporary Securities shall in all
respects be entitled to the same benefits under this Indenture as Definitive
Securities.

          Section  3.5  Registration, Registration of Transfer and Exchange.
The Company shall cause to be kept at the Corporate Trust Office a register (the
register maintained in such office and in any other office or agency designated
pursuant to Section 10.2 hereof being herein sometimes referred to as the
"Security Register") in which, subject to such reasonable regulations as it may
prescribe, the Company shall provide for the registration of Securities and of
transfers of Securities. The Security Register shall be in written form or any
other form capable of being converted into written form within a reasonable
time.  At all reasonable times and during normal business hours, the Security
Register shall be open to inspection by the Trustee.  The Trustee is hereby
initially appointed as security registrar (the "Security Registrar") for the
purpose of registering Securities and transfers of Securities as herein
provided.

          The Company initially appoints The Depository Trust Company to act as
Depositary with respect to the Global Security.

          Section 3.6 Transfer and Exchange.

          (a) Transfer and Exchange of Definitive Securities.  When Definitive
Securities are presented to the Securities Registrar with the request:

          (x) to register the transfer of the Definitive Securities, or

               (y) to exchange such Definitive Securities for an equal principal
     amount of Definitive Securities of other authorized denominations,

                                       52
<PAGE>
 
the Securities Registrar shall register the transfer or make the exchange as
requested if its requirement for such transactions are met; provided, however,
that the Definitive Securities presented or surrendered for registration of
transfer or exchange:

               (i) shall be duly endorsed or accompanied by a written instrument
     of transfer in form satisfactory to the Securities Registrar duly executed
     by the Holder thereof or by his attorney, duly authorized in writing; and

               (ii  in the case of Transfer Restricted Securities that are
     Definitive Securities, shall be accompanied by the following additional
     information and documents, as applicable, upon which the Securities
     Registrar may conclusively rely:

                    (A) if such Transfer Restricted Securities are being
          delivered to the Registrar by a Holder for registration in the name of
          such Holder, without transfer, a certification from such Holder to
          that effect (in substantially the form of Exhibit A hereto); or

                    (B) if such Transfer Restricted Securities are being
          transferred (1) to a "qualified institutional buyer" (as defined in
          Rule 144A under the Securities Act) in accordance with Rule 144A under
          the Securities Act or (2) pursuant to an exemption from registration
          in accordance with Rule 144 under the Securities Act (and based upon
          an opinion of counsel if the Company or the Trustee so requests) or
          (3) pursuant to an effective registration statement under the
          Securities Act, a certification to that effect from such Holder (in
          substantially the form of Exhibit A hereto); or

                    (C) if such Transfer Restricted Securities are being
          transferred to an institutional "accredited investor," within the
          meaning of Rule 501 (a)(1), (2), (3) or (7) under the Securities Act
          pursuant to a private placement exemption from the registration
          requirements of the Securities Act, a certification to that effect
          from such Holder (in substantially the form of Exhibit A hereto) and a
          certification from the applicable transferee (in substantially the
          form of Exhibit B hereto) and an opinion of counsel to that effect if
          the Company or the Trustee so requests;

                    (D) if such Transfer Restricted Securities are being
          transferred pursuant to an exemption from registration in accordance
          with Rule 904 under the Securities Act, certifications to that effect
          from such Holder (in substantially the form of Exhibits A and C
          hereto) and an opinion of counsel to that effect if the Company or the
          Trustee so requests; or

                    (E) if such Transfer Restricted Securities are being
          transferred in reliance on another exemption from the registration
          requirements of the Securities Act, a certification to that effect
          from such Holder (in substantially the form of Exhibit A 

                                       53
<PAGE>
 
          hereto) and an opinion of counsel to that effect if the Company or
          the Trustee so requests.

          (b) Restriction on Transfer of a Definitive Security for a Beneficial
Interest in a Global Security.  A Definitive Security may not be exchanged for a
beneficial interest in a Global Security except upon satisfaction of the
requirements set forth below.  Upon receipt by the Trustee of a Definitive
Security, duly endorsed or accompanied by appropriate instruments of transfer,
in form satisfactory to the Trustee, together with the following additional
information and documents, as applicable, upon which the Trustee may
conclusively rely:

               (i) if such Definitive Security is a Transfer Restricted
     Security, certification, substantially in the form of Exhibit A hereto that
     such Definitive Security is being transferred to a "qualified institutional
     buyer" (as defined in Rule 144A under the Securities Act) in accordance
     with Rule 144A under the Securities Act; or

               (ii) if such Definitive Security is a Transfer Restricted
     Security and is being transferred pursuant to an exemption from
     registration in accordance with Rule 904 under the Securities Act,
     certifications to that effect from such Holder (in substantially the form
     of Exhibits A and C hereto) and an opinion of counsel to that effect if the
     Company or Trustee so requests; and

               (iii) whether or not such Definitive Security is a Transfer
     Restricted Security written instructions directing the Trustee to make, or
     direct the Security Custodian to make, an endorsement on the Global
     Security to reflect an increase in the aggregate principal amount of the
     Securities represented by the Global Security;

then the Trustee shall cancel such Definitive Security in accordance with
Section 3.11 hereof and cause, or direct the Security Custodian to cause, in
accordance with the standing instructions and procedures existing between the
Depositary and the Security Custodian, the aggregate principal amount of
Securities represented by the Global Security to be increased accordingly.  If
no Global Securities are then outstanding, the Company shall issue and the
Trustee shall authenticate a new Global Security in the appropriate principal
amount.

          (c) Transfer and Exchange of Global Securities.  The transfer and
exchange of Global Securities or beneficial interests therein shall be effected
through the Depositary, in accordance with this Indenture (including the
restrictions on transfer set forth herein) and the procedures of the Depositary
therefor, which shall include restrictions on transfer comparable to those set
forth herein to the extent required by the Securities Act.

          (d) Transfer of a Beneficial Interest in a Global Security for a
Definitive Security.

               (i) Any Person having a beneficial interest in a Global Security
     may upon request exchange such beneficial interest for a Definitive
     Security.  Upon receipt by the Trustee of 

                                       54
<PAGE>
 
     written instructions or such other form of instructions as is customary for
     the Depositary, from the Depositary or its nominee on behalf of any Person
     having a beneficial interest in a Global Security, and in the case of a
     Transfer Restricted Security, the following additional information and
     documents (all of which may be submitted by facsimile), upon which the
     Trustee may conclusively rely:

                    (A) if such beneficial interest is being transferred to the
          Person designated by the Depositary as being the beneficial owner, a
          certification from such Person to that effect (in substantially the
          form of Exhibit A hereto); or

                    (B) if such beneficial interest is being transferred (1) to
          a "qualified institutional buyer" (as defined in Rule 144A under the
          Securities Act) in accordance with Rule 144A under the Securities Act
          or (2) pursuant to an exemption from registration in accordance with
          Rule 144 under the Securities Act (and based upon an opinion of
          counsel to that effect if the Company or the Trustee so requests) or
          (3) pursuant to an effective registration statement under the
          Securities Act, a certification to that effect from the transferor (in
          substantially the form of Exhibit A hereto); or

                    (C) if such beneficial interest is being transferred to an
          institutional "accredited investor," within the meaning of Rule 501
          (a)(1), (2), (3) or (7) under the Securities Act pursuant to a private
          placement exemption from the registration requirements of the
          Securities Act (and based upon an opinion of counsel to that effect if
          the Company or the Trustee so requests), a certification to that
          effect from such transferor (in substantially the form of Exhibit A
          hereto) and a certification from the applicable transferee (in
          substantially the form of Exhibit B hereto); or

                    (D) if such beneficial interest is being transferred
          pursuant to an exemption from registration in accordance with Rule 904
          under the Securities Act (and based upon an opinion to that effect of
          counsel if the Company or the Trustee so requests), certifications to
          that effect from such transferor (in substantially the form of
          Exhibits A and C hereto); or

                    (E) if such beneficial interest is being transferred in
          reliance on another exemption from the registration requirements of
          the Securities Act (and based upon an opinion of counsel to that
          effect if the Company or the Trustee so requests), a certification to
          that effect from such transferor (in substantially the form of Exhibit
          A hereto);

the Trustee or the Security Custodian, at the direction of the Trustee, shall,
in accordance with the standing instructions and procedures existing between the
Depositary and the Security Custodian, cause the aggregate principal amount of
Global Securities to be reduced accordingly and, following such reduction, the
Company shall execute and the Trustee shall authenticate and deliver to the
transferee a Definitive Security in the appropriate principal amount.

                                       55
<PAGE>
 
               (ii)  Definitive Securities issued in exchange for a beneficial
     interest in a Global Security pursuant to this Section 3.6(d) shall be
     registered in such names and in such authorized denominations as the
     Depositary, pursuant to instructions from its direct or indirect
     participants or otherwise, shall instruct the Trustee.  The Trustee shall
     deliver such Definitive Securities to the Persons in whose names such
     Securities are so registered.

          (e) Restrictions on Transfer and Exchange of Global Securities.
Notwithstanding any other provisions of this Indenture (other than the
provisions set forth in subsection (f) of this Section 3.6), a Global Security
may not be transferred as a whole except by the Depositary to a nominee of the
Depositary or by a nominee of the Depositary to the Depositary or another
nominee of the Depositary or by the Depositary or any such nominee to a
successor Depositary or a nominee of such successor Depositary.

          (f) Authentication of Definitive Securities in Absence of Depositary.
If at any time:

               (i) the Depositary for the Securities notifies the Company that
     the Depositary is unwilling or unable to continue as Depositary for the
     Global Securities and a successor Depositary for the Global Securities is
     not appointed by the Company within 90 days after delivery of such notice;

               (ii) an Event of Default has occurred and is continuing and the
     Security Registrar has received a request from the Depositary to issue
     Definitive Securities in lieu of all or a portion of the Global Security
     (in which case the Company shall deliver Definitive Securities within 30
     days of such request); or

               (iii) the Company, at its sole discretion, notifies the Trustee
     in writing that it elects to cause the issuance of Definitive Securities
     under this Indenture,

then the Company will execute, and the Trustee will authenticate and deliver
Definitive Securities, in an aggregate principal amount equal to the principal
amount of the Global Securities, in exchange for such Global Securities and
registered in such names as the Depositary shall instruct the Trustee or the
Company in writing.

          (g)  Legends.

               (i) Except as permitted by the following paragraphs (ii) and
     (iii) immediately below, each Security certificate evidencing the Global
     Securities and the Definitive Securities (and all Securities issued in
     exchange therefor or substitution thereof) shall bear a legend in
     substantially the following form:

          THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
     1933, AS AMENDED ( THE "SECURITIES ACT"), OR ANY STATE 

                                       56
<PAGE>
 
     SECURITIES LAWS. NEITHER THIS SECURITY NOR ANY INTEREST OR PARTICIPATION
     HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED
     OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH
     TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, THE REGISTRATION
     REQUIREMENTS OF THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES
     LAWS. THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES (1) NOT
     TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO (X) THE DATE
     THAT IS TWO YEARS (OR SUCH SHORTER PERIOD OF TIME AS PERMITTED BY RULE
     144(k) UNDER THE SECURITIES ACT OR ANY SUCCESSOR PROVISION THEREUNDER)
     AFTER THE LATER OF THE ORIGINAL ISSUE DATE HEREOF (OR OF ANY PREDECESSOR OF
     THIS SECURITY) AND THE LAST DAY ON WHICH OCEAN ENERGY, INC. (THE "COMPANY")
     OR ANY AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS SECURITY (OR ANY
     PREDECESSOR OF THIS SECURITY) AND (Y) SUCH LATER DATE, IF ANY, AS MAY BE
     REQUIRED BY APPLICABLE LAWS (THE "RESALE RESTRICTION TERMINATION DATE"),
     EXCEPT (A) TO THE COMPANY, (B) PURSUANT TO AN EFFECTIVE REGISTRATION
     STATEMENT UNDER THE SECURITIES ACT, (C) FOR SO LONG AS THIS SECURITY IS
     ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES ACT ("RULE
     144A"), TO A PERSON IT REASONABLY BELIEVES IS A "QUALIFIED INSTITUTIONAL
     BUYER" AS DEFINED IN RULE 144A THAT IS ACQUIRING SUCH SECURITY FOR ITS OWN
     ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM
     NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A,
     (D) PURSUANT TO OFFERS AND SALES TO NON-U.S. PERSONS THAT OCCUR OUTSIDE THE
     UNITED STATES WITHIN THE MEANING OF REGULATION S UNDER THE SECURITIES ACT,
     OR (E) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION
     REQUIREMENTS OF THE SECURITIES ACT, AND (2) THAT IT WILL GIVE TO EACH
     PERSON TO WHOM THIS SECURITY IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE
     EFFECT OF THIS LEGEND; PROVIDED THAT THE COMPANY, THE TRUSTEE, THE TRANSFER
     AGENT AND THE REGISTRAR SHALL HAVE THE RIGHT PRIOR TO ANY SUCH OFFER, SALE
     OR TRANSFER (i) PURSUANT TO CLAUSES (D) OR (E) TO REQUIRE THE DELIVERY OF
     AN OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY
     TO EACH OF THEM, AND (ii) IN EACH OF THE FOREGOING CASES, TO REQUIRE THAT A
     CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THIS SECURITY IS COMPLETED
     AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE. THIS LEGEND WILL BE REMOVED
     UPON THE REQUEST OF A HOLDER AFTER THE RESALE RESTRICTION TERMINATION DATE.
     THE HOLDER HEREOF, BY PURCHASING THIS NOTE, REPRESENTS AND AGREES FOR THE
     BENEFIT OF THE COMPANY THAT IT IS (1) A QUALIFIED INSTITUTIONAL BUYER
     WITHIN THE MEANING OF RULE 144A OR (2) A NON-U.S. PERSON AND IS ACQUIRING
     THE NOTE IN AN "OFFSHORE 

                                       57
<PAGE>
 
     TRANSACTION" PURSUANT TO RULE 904 OF REGULATION S UNDER THE SECURITIES ACT.
     THIS LEGEND WILL BE REMOVED UPON THE REQUEST OF THE HOLDER AFTER THE RESALE
     RESTRICTION TERMINATION DATE. AS USED HEREIN, THE TERMS "OFFSHORE
     TRANSACTION," "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANING GIVEN TO
     THEM BY REGULATION S UNDER THE SECURITIES ACT.

Each Security certificate evidencing the Global Securities also shall bear the
paragraph referred to in the first footnote of the form of Security in Section
2.2 hereof.

               (ii) Upon any sale or transfer of a Transfer Restricted Security
     (including any Transfer Restricted Security represented by a Global
     Security) pursuant to Rule 144 under the Securities Act or an effective
     registration statement under the Securities Act, which shall be certified
     to the Trustee and Security Registrar upon which each may conclusively
     rely:

                    (A) in the case of any Transfer Restricted Security that is
          a Definitive Security, the Security Registrar shall permit the Holder
          thereof to exchange such Transfer Restricted Security for a Definitive
          Security that does not bear the legend set forth in (i) above and
          rescind any restriction on the transfer of such Transfer Restricted
          Security; and

                    (B) in the case of any Transfer Restricted Security
          represented by a Global Security, such Transfer Restricted Security
          shall not be required to bear the legend set forth in (i) above if all
          other interests in such Global Security have been or are concurrently
          being sold or transferred pursuant to Rule 144 under the Securities
          Act or pursuant to an effective registration statement under the
          Securities Act, but such Transfer Restricted Security shall continue
          to be subject to the provisions of Section 3.6(c) hereof; provided,
          however, that with respect to any request for an exchange of a
          Transfer Restricted Security that is represented by a Global Security
          for a Definitive Security that does not bear a legend set forth in (i)
          above, which request is made in reliance upon Rule 144 under the
          Securities Act, the Holder thereof shall certify in writing to the
          Security Registrar that such request is being made pursuant to Rule
          144 under the Securities Act (such certification to be substantially
          in the form of Exhibit A hereto and upon which the Security Registrar
          may conclusively rely).

               (iii) Notwithstanding the foregoing, upon consummation of the
     Exchange Offer, the Company shall issue and, upon receipt of an
     authentication order in accordance with Section 3.3 hereof, the Trustee
     shall authenticate Series B Securities in exchange for Series A Securities
     accepted for exchange in the Exchange Offer, which Series B Securities
     shall not bear the legend set forth in (i) above, and the Security
     Registrar shall rescind any restriction on the transfer of such Securities,
     in each case unless the Holder of such Series A Securities is either (A) a
     broker-dealer, (B) a Person participating in the distribution of the Series
     A Securities or (C) a Person who is an affiliate (as defined in Rule 144
     under the

                                       58
<PAGE>
 
     Securities Act) of the Company.  The Company shall identify to the Trustee
     such Holders of the Securities in a written certification signed by an
     Officer of the Company and, absent certification from the Company to such
     effect, the Trustee shall assume that there are no such Holders.

          (h) Cancellation and/or Adjustment of Global Security. At such time as
all beneficial interests in a Global Security have either been exchanged for
Definitive Securities, redeemed, repurchased or canceled, such Global Security
shall be returned to or retained and canceled by the Trustee. At any time prior
to such cancellation, if any beneficial interest in a Global Security is
exchanged for Definitive Securities, redeemed, repurchased or canceled, the
principal amount of Securities represented by such Global Security shall be
reduced and an endorsement shall be made on such Global Security, by the Trustee
or the Security Custodian, at the direction of the Trustee to reflect such
reduction.

          (i) General Provisions with respect to Transfer and Exchanges.

          (i) To permit registrations of transfers and exchanges, the Company
     shall execute and the Trustee shall authenticate Definitive Securities and
     Global Securities at the Security Registrar's request.

          (ii) No service charge shall be made to a Holder for any registration
     of transfer or exchange or redemption of Securities (except as otherwise
     permitted herein), but the Company may require payment of a sum sufficient
     to cover any transfer tax or similar governmental charge payable in
     connection therewith (other than such transfer tax or similar governmental
     charge payable upon exchanges pursuant to the last paragraph of Section 3.3
     or Sections 3.4, 9.6 or 11.8 hereof).

          (iii) The Trustee shall authenticate Definitive Securities and Global
     Securities in accordance with the provisions of Section 3.3 hereof.

          (iv) Notwithstanding any other provisions of this Indenture to the
     contrary, the Company shall not be required to register the transfer or
     exchange of a Security between a Regular Record Date and the next
     succeeding Interest Payment Date.

          (v) Neither the Company nor the Trustee will have any responsibility
     or liability for any aspect of the records relating to, or payments made on
     account of, Securities by the Depositary, or for maintaining, supervising
     or reviewing any records of the Depositary relating to such Securities.
     Neither the Company nor the Trustee shall be liable for any delay by the
     related Global Security Holder or the Depositary in identifying the
     beneficial owners of the related Securities and each such Person may
     conclusively rely on, and shall be protected in relying on, instructions
     from such Global Security Holder or the Depositary for all purposes
     (including with respect to the registration and delivery, and the
     respective principal amounts, of the Securities to be issued).

                                       59
<PAGE>
 
          (vi) Neither the Trustee, the Security Registrar nor the Company shall
     be required (A) to issue, register the transfer of or exchange any Security
     during a period beginning at the opening of business 15 days before the
     mailing of a notice of redemption of Securities selected for redemption
     under Section 11.4 hereof and ending at the close of business on the day of
     such mailing of the relevant notice of redemption, or (B) to register the
     transfer of or exchange any Security so selected for redemption in whole or
     in part, except the unredeemed portion of any Security being redeemed in
     part.

          (vii) All Securities and the Subsidiaries Guarantees, if any, noted
     thereon issued upon any registration of transfer or exchange of Securities
     shall be the valid obligations of the Company and the respective Subsidiary
     Guarantors, if any, evidencing the same debt, and entitled to the same
     benefits under this Indenture, as the Securities surrendered upon such
     registration of transfer or exchange.

          (viii) Each Holder of a Security agrees to indemnify the Company and
     the Trustee against any liability that may result from the transfer,
     exchange or assignment of such Holder's Security in violation of any
     provision of this Indenture and/or applicable federal or state securities
     law.

          (ix) The Trustee shall have no obligation or duty to monitor,
     determine or inquire as to compliance with any restrictions on transfer
     imposed under this Indenture or under applicable law with respect to any
     transfer of any interest in any Security other than to require delivery of
     such certificates and other documentation or evidence as are expressly
     required by, and to do so if and when expressly required by the terms of,
     this Indenture, and to examine the same to determine substantial compliance
     as to form with the express requirements hereof.

     Section 3.7   Additional Provisions for Global Security.

          (a) The Global Security initially shall be registered in the name of
the Depositary for such Global Security or the nominee of such Depositary and be
delivered to the Trustee as custodian for, such Depositary.

          Members of or participants in, the Depositary ("Agent Members") shall
have no rights under this Indenture with respect to any Global Security held on
their behalf by the Depositary, or the Trustee as its custodian, or under the
Global Security, and the Depositary may be treated by the Company, the Trustee
and any agent of the Company or the Trustee as the absolute owner of such Global
Security for all purposes whatsoever.  Notwithstanding the foregoing, nothing
herein shall prevent the Company, the Trustee or any agent of the Company or the
Trustee, from giving effect to any written certification, proxy or other
authorization furnished by the Depositary or shall impair, as between the
Depositary and its Agent Members, the operation of customary practices governing
the exercise of the rights of a Holder of any Security.

                                       60
<PAGE>
 
          (b) The registered Holder of the Global Security may grant proxies and
otherwise authorize any Person, including Agent Members and Persons that may
hold interests through Agent Members, to take any action which a Holder is
entitled to take under this Indenture or the Securities.

     Section 3.8 Mutilated, Destroyed, Lost and Stolen Securities.  If (i) any
mutilated Security is surrendered to the Trustee or (ii) the Company and the
Trustee receive evidence to their satisfaction of the destruction, loss or theft
of any Security, and there is delivered to the Company, the Subsidiary
Guarantors and the Trustee such security or indemnity as may be required by them
to save each of them harmless, then, in the absence of notice to the Company or
the Trustee that such Security has been acquired by a bona fide purchaser, the
Company shall execute, the Subsidiary Guarantors shall execute the notations of
Subsidiary Guarantees, and upon Company Order the Trustee shall authenticate and
deliver, in exchange for any such mutilated Security or in lieu of any such
destroyed, lost or stolen Security, a new Security of like tenor and principal
amount, having the notations of Subsidiary Guarantees thereon bearing a number
not contemporaneously outstanding.

          In case any such mutilated, destroyed, lost or stolen Security has
become or is about to become due and payable, the Company in its discretion may,
instead of issuing a new Security, pay such Security.

          Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

          Every new Security issued pursuant to this Section in lieu of any
mutilated, destroyed, lost or stolen Security shall constitute an original
additional contractual obligation of the Company and the respective Subsidiary
Guarantors, whether or not the mutilated, destroyed, lost or stolen Security
shall be at any time enforceable by anyone, and shall be entitled to all
benefits of this Indenture equally and proportionately with any and all other
Securities duly issued hereunder.

          The provisions of this Section are exclusive and shall preclude (to
the extent lawful) all other rights and remedies with respect to the replacement
or payment of mutilated, destroyed, lost or stolen Securities.

     Section 3.9 Payment of Interest; Interest Rights Preserved. Interest on any
Security which is payable, and is punctually paid or duly provided for, on any
Interest Payment Date shall be paid to the Person in whose name such Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest, or, in the case of interest
payable at the Maturity of the principal of the Securities, to the Person to
whom principal is paid, in each case at the office or agency of the Company
maintained for such purpose pursuant to Section 10.2 hereof.

                                       61
<PAGE>
 
          Any interest on any Security which is payable, but is not punctually
paid or duly provided for, on any Interest Payment Date shall forthwith cease to
be payable to the Holder on the Regular Record Date by virtue of having been
such Holder, and such defaulted interest and (to the extent lawful) interest on
such defaulted interest at the rate borne by the Securities (such defaulted
interest and interest thereon herein collectively called "Defaulted Interest")
may be paid by the Company, at its election in each case, as provided in clause
(a) or (b) below:

          (a) The Company may elect to make payment of any Defaulted Interest to
the Persons in whose names the Securities (or their respective Predecessor
Securities) are registered, at the close of business on a Special Record Date
for the payment of such Defaulted Interest, which shall be fixed in the
following manner. The Company shall notify the Trustee in writing of the amount
of Defaulted Interest proposed to be paid on each Security and the date of the
proposed payment, and at the same time the Company shall deposit with the
Trustee an amount of money equal to the aggregate amount proposed to be paid in
respect of such Defaulted Interest or shall make arrangements satisfactory to
the Trustee for such deposit prior to the date of the proposed payment, such
money when deposited shall be held in trust for the benefit of the Persons
entitled to such Defaulted Interest as in this clause provided. Thereupon the
Trustee shall fix a Special Record Date for the payment of such Defaulted
Interest which shall be not more than 15 days and not less than 10 days prior to
the date of the proposed payment and not less than 10 days after the receipt by
the Trustee of the notice of the proposed payment. The Trustee shall promptly
notify the Company of such Special Record Date, and in the name and at the
expense of the Company, shall cause notice of the proposed payment of such
Defaulted Interest and the Special Record Date therefor to be given in the
manner provided for in Section 15.5 hereof, not less than 10 days prior to such
Special Record Date. Notice of the proposed payment of such Defaulted Interest
and the Special Record Date therefor having been so given, such Defaulted
Interest shall be paid to the Persons in whose names the Securities (or their
respective Predecessor Securities) are registered at the close of business on
such Special Record Date and shall no longer be payable pursuant to the
following clause (b).

          (b) The Company may make payment of any Defaulted Interest in any
other lawful manner not inconsistent with the requirements of any securities
exchange on which the Securities may be listed, and upon such notice as may be
required by such exchange, if, after notice given by the Company to the Trustee
of the proposed payment pursuant to this clause, such manner of payment shall be
deemed practicable by the Trustee.

          Subject to the foregoing provisions of this Section, each Security
delivered under this Indenture upon registration of transfer of or in exchange
for or in lieu of any other Security shall carry the rights to interest accrued
and unpaid, and to accrue, which were carried by such other Security.

     Section 3.10  Persons Deemed Owners.  Prior to the due presentment of a
Security for registration of transfer, the Company, the Subsidiary Guarantors,
the Security Registrar, the Trustee and any agent of the Company, the Subsidiary
Guarantors or the Trustee may treat the Person in whose name such Security is
registered as the owner of such Security for the purpose of receiving 

                                       62
<PAGE>
 
payment of principal of (and premium, if any, on) and (subject to Section 3.9
hereof) interest on such Security and for all other purposes whatsoever, whether
or not such Security be overdue, and none of the Company, the Subsidiary
Guarantors, the Security Registrar, the Trustee or any agent of the Company, the
Subsidiary Guarantors or the Trustee shall be affected by notice to the
contrary.

     Section 3.11 Cancellation.  All Securities surrendered for payment,
redemption, registration of transfer or exchange shall, if surrendered to any
Person other than the Trustee, be delivered to the Trustee and shall be promptly
canceled by it.  The Company may at any time deliver to the Trustee for
cancellation any Securities previously authenticated and delivered hereunder
which the Company may have acquired in any manner whatsoever, and all Securities
so delivered shall be promptly canceled by the Trustee.  No Securities shall be
authenticated in lieu of or in exchange for any Securities canceled as provided
in this Section, except as expressly permitted by this Indenture.  All canceled
Securities held by the Trustee shall be destroyed and a certificate of their
destruction delivered to the Company unless by a Company Order the Company shall
direct that canceled Securities be returned to it.

     Section 3.12  Computation of Interest.  Interest on the Securities shall be
computed on the basis of a 360-day year comprised of twelve 30-day months.

     Section 3.13 CUSIP Numbers.  The Company in issuing the Securities may use
"CUSIP" numbers (if then generally in use), and, if so, the Trustee shall use
"CUSIP" numbers in notices of redemption as a convenience to Holders; provided,
that any such notice may state that no representation is made as to the
correctness of such numbers either as printed on the Securities or as contained
in any notice of a redemption and that reliance may be placed only on the other
identification numbers printed on the Securities, and any such redemption shall
not be affected by any defect in or omission of such numbers.  The Company will
promptly notify the Trustee of any change in the CUSIP numbers.

                                  ARTICLE IV

                          SATISFACTION AND DISCHARGE
                          --------------------------

     Section 4.1 Satisfaction and Discharge of Indenture.  This Indenture shall
upon Company Request be discharged and cease to be of further effect (except as
to surviving rights of registration of transfer or exchange of Securities, as
expressly provided for in this Indenture) as to all outstanding Securities, and
the Trustee, at the expense of the Company, shall, upon payment of all amounts
due the Trustee under Section 6.6 hereof, execute proper instruments
acknowledging satisfaction and discharge of this Indenture when

          (a) either

              (i) all Securities theretofore authenticated and delivered (other
     than (1) Securities which have been mutilated, destroyed, lost or stolen
     and which have been replaced or paid 

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<PAGE>
 
     as provided in Section 3.8 hereof and (2) Securities for whose payment
     money or United States governmental obligations of the type described in
     clause (i) of the definition of Cash Equivalents has theretofore been
     deposited in trust with the Trustee or any Paying Agent or segregated and
     held in trust by the Company and thereafter repaid to the Company or
     discharged from such trust, as provided in Section 10.3 hereof) have been
     delivered to the Trustee for cancellation, or

              (i) all such Securities not theretofore delivered to the Trustee
     for cancellation

                  (A) have become due and payable, or

                  (B) will become due and payable at their Stated Maturity
          within one year, or

                  (C) are to be called for redemption within one year under
          arrangements satisfactory to the Trustee for the giving of notice of
          redemption by the Trustee in the name, and at the expense, of the
          Company,

          and the Company, in the case of (ii)(A), (ii)(B) or (ii)(C) above, has
          irrevocably deposited or caused to be deposited with the Trustee as
          trust funds in trust for the purpose an amount sufficient to pay and
          discharge the entire indebtedness on such Securities not theretofore
          delivered to the Trustee for cancellation, for principal (and premium,
          if any) and interest to the date of such deposit (in the case of
          Securities which have become due and payable) or to the Stated
          Maturity or Redemption Date, as the case may be, together with
          instructions from the Company irrevocably directing the Trustee to
          apply such funds to the payment thereof at maturity or redemption, as
          the case may be;

          (b) the Company has paid or caused to be paid all other sums payable
hereunder by the Company; and

          (c) the Company has delivered to the Trustee an Officers' Certificate
and an Opinion of Counsel each satisfactory in form to the Trustee, which, taken
together, state that all conditions precedent herein relating to the
satisfaction and discharge of this Indenture have been complied with.

          Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under Section 6.6 hereof and, if money
shall have been deposited with the Trustee pursuant to this Section, the
obligations of the Trustee under Section 4.2 hereof and the last paragraph of
Section 10.3 hereof shall survive.

     Section 4.2  Application of Trust Money.  Subject to the provisions of the
last paragraph of Section 10.3 hereof, all money deposited with the Trustee
pursuant to Section 4.1 hereof shall be 

                                       64
<PAGE>
 
held in trust and applied by it, in accordance with the provisions of the
Securities and this Indenture, to the payment, either directly or through any
Paying Agent (including the Company acting as its own Paying Agent) as the
Trustee may determine, to the Persons entitled thereto, of the principal (and
premium, if any) and interest for whose payment such money has been deposited
with the Trustee.

                                   ARTICLE V

                                   REMEDIES
                                   --------

     Section 5.1  Events of Default.  "Events of Default," wherever used herein,
means any one of the following events (whatever the reason for such Event of
Default and whether it shall be voluntary or involuntary or be effected by
operation of law or pursuant to any judgment, decree or order of any court or
any order, rule or regulation of any administrative or governmental body):

          (a) default in the payment of the principal of or premium, if any, on
any of the Securities, whether such payment is due at maturity, upon redemption,
upon repurchase pursuant to a Change of Control Offer or a Net Proceeds Offer,
upon acceleration or otherwise; or

          (b) default in the payment of any installment of interest on any of
the Securities, when it becomes due and payable, and the continuance of such
default for a period of 30 days; or

          (c) default in the performance or breach of the provisions of Article
VIII hereof, the failure to make or consummate a Change of Control Offer in
accordance with the provisions of Section 10.16 or the failure to make or
consummate a Net Proceeds Offer in accordance with the provisions of Section
10.17; or

          (d) the Company or any Subsidiary Guarantor shall fail to perform or
observe any other term, covenant or agreement contained in the Securities, any
Subsidiary Guarantee or this Indenture (other than a default specified in (a),
(b) or (c) above) for a period of 30 days after written notice of such failure
stating that it is a "notice of default" hereunder and requiring the Company or
such Subsidiary Guarantor to remedy the same shall have been given (i) to the
Company by the Trustee or (ii) to the Company and the Trustee by the holders of
at least 25% in aggregate principal amount of the Securities then Outstanding;
or

          (e) the occurrence and continuation beyond any applicable grace period
of any default in the payment of the principal of (or premium, if any, on) or
interest on any Indebtedness of the Company (other than the Securities) or any
Subsidiary Guarantor or any other Restricted Subsidiary for money borrowed when
due, or any other default causing acceleration of any Indebtedness of the
Company or any Subsidiary Guarantor or any other Restricted Subsidiary for money
borrowed, provided that the aggregate principal amount of such Indebtedness
shall exceed the greater of (i) $20 million and (ii) 5% of Adjusted Consolidated
Net Tangible Assets; provided further that if any such default is cured or
waived or any such acceleration rescinded, or such debt 

                                       65
<PAGE>
 
is repaid, within a period of 10 days from the continuation of such default
beyond the applicable grace period or the occurrence of such acceleration, as
the case may be, such Event of Default under this Indenture and any
consequential acceleration of the Securities shall be automatically rescinded,
so long as such rescission does not conflict with any judgment or decree; or

          (f) the commencement of proceedings, or the taking of any enforcement
action (including by way of set-off), by any holder of at least the greater of
(i) $20 million and (ii) 5% of Adjusted Consolidated Net Tangible Assets in
aggregate principal amount of Indebtedness of the Company or any Subsidiary
Guarantor or any other Restricted Subsidiary, after a default under such
Indebtedness, to retain in satisfaction of such Indebtedness or to collect or
seize, dispose of or apply in satisfaction of such Indebtedness, Property or
assets of the Company or any Subsidiary Guarantor or any other Restricted
Subsidiary having a Fair Market Value (as determined by the Board of Directors
of the Company and evidenced by a Board Resolution) in excess of the greater of
(i) $20 million and (ii) 5% of Adjusted Consolidated Net Tangible Assets
individually or in the aggregate, provided that if any such proceedings or
actions are terminated or rescinded, or such Indebtedness is repaid, such Event
of Default under this Indenture and any consequential acceleration of the
Securities shall be automatically rescinded, so long as (x) such rescission does
not conflict with any judgment or decree and (y) the holder of such Indebtedness
shall not have applied any such property or assets in satisfaction of such
Indebtedness; or

          (g) any Subsidiary Guarantee shall for any reason cease to be, or be
asserted by the Company or any Subsidiary Guarantor, as applicable, not to be,
in full force and effect, enforceable in accordance with its terms (except
pursuant to the release of any such Subsidiary Guarantee in accordance with this
Indenture); or

          (h) final judgments or orders rendered against the Company or any
Subsidiary Guarantor or any other Restricted Subsidiary that are unsatisfied and
that require the payment in money, either individually or in an aggregate
amount, that is more than the greater of (i) $20 million and (ii) 5% of Adjusted
Consolidated Net Tangible Assets over the coverage under applicable insurance
policies and either (x) commencement by any creditor of an enforcement
proceeding upon such judgment (other than a judgment that is stayed by reason of
pending appeal or otherwise) or (y) the occurrence of a 60-day period during
which a stay of such judgment or order, by reason of pending appeal or
otherwise, was not in effect; or

          (i) the entry of a decree or order by a court having jurisdiction in
the premises (i) for relief in respect of the Company, any Subsidiary Guarantor
or any Significant Subsidiary in an involuntary case or proceeding under the
Federal Bankruptcy Code or any other applicable federal or state bankruptcy,
insolvency, reorganization or other similar law or (ii) adjudging the Company,
any Subsidiary Guarantor or any Significant Subsidiary bankrupt or insolvent, or
approving a petition seeking reorganization, arrangement, adjustment or
composition of the Company, any Subsidiary Guarantor or any Significant
Subsidiary under the Federal Bankruptcy Code or any other applicable federal or
state law, or appointing under any such law a custodian, receiver, liquidator,
assignee, trustee, sequestrator or other similar official of the Company, any
Subsidiary Guarantor 

                                       66
<PAGE>
 
or any Significant Subsidiary or of a substantial part of their consolidated
assets, or ordering the winding up or liquidation of their affairs, and the
continuance of any such decree or order for relief or any such other decree or
order unstayed and in effect for a period of 60 consecutive days; or

          (j) the commencement by the Company, any Subsidiary Guarantor or any
Significant Subsidiary of a voluntary case or proceeding under the Federal
Bankruptcy Code or any other applicable federal or state bankruptcy, insolvency,
reorganization or other similar law or any other case or proceeding to be
adjudicated a bankrupt or insolvent, or the consent by the Company, any
Subsidiary Guarantor or any Significant Subsidiary to the entry of a decree or
order for relief in respect thereof in an involuntary case or proceeding under
the Federal Bankruptcy Code or any other applicable federal or state bankruptcy,
insolvency, reorganization or other similar law or to the commencement of any
bankruptcy or insolvency case or proceeding against it, or the filing by the
Company, any Subsidiary Guarantor or any Significant Subsidiary of a petition or
consent seeking reorganization or relief under any applicable federal or state
law, or the consent by it under any such law to the filing of any such petition
or to the appointment of or taking possession by a custodian, receiver,
liquidator, assignee, trustee or sequestrator (or other similar official) of any
of the Company, any Subsidiary Guarantor or any Significant Subsidiary or of any
substantial part of their consolidated assets, or the making by it of an
assignment for the benefit of creditors under any such law, or the admission by
it in writing of its inability to pay its debts generally as they become due or
taking of corporate action by the Company, any Subsidiary Guarantor or any
Significant Subsidiary in furtherance of any such action.

     Section 5.2 Acceleration of Maturity; Rescission and Annulment. If an Event
of Default (other than an Event of Default specified in clause (i) or (j) of
Section 5.1 hereof) shall occur and be continuing, the Trustee, by written
notice to the Company, or the holders of at least 25% in aggregate principal
amount of the Securities then Outstanding, by notice to the Trustee and the
Company, may declare the principal of, premium, if any, and accrued interest on
all of the Outstanding Securities due and payable immediately, upon which
declaration all amounts payable in respect of the Securities shall be
immediately due and payable. If an Event of Default specified in Section 5.1(i)
or (j) hereof occurs and is continuing, then the principal of, premium, if any,
and accrued interest on all of the Outstanding Securities shall ipso facto
become and be immediately due and payable without any declaration, notice or
other act on the part of the Trustee or any Holder of Securities.

          After a declaration of acceleration has been made and before a
judgment or decree for payment of the money due has been obtained by the
Trustee, the Holders of a majority in aggregate principal amount of the
Securities Outstanding, by written notice to the Company and the Trustee, may
rescind and annul such declaration and its consequences if (a) the Company or
any Subsidiary Guarantor has paid or deposited with the Trustee a sum sufficient
to pay (i) all sums paid or advanced by the Trustee hereunder and the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agents
and counsel, (ii) all overdue interest on all Securities, (iii) the principal of
and premium, if any, on any Securities which have become due otherwise than by
such declaration of acceleration and interest thereon at the rate borne by the
Securities, and (iv) to the 

                                       67
<PAGE>
 
extent that payment of such interest is lawful, interest upon overdue interest
and overdue principal at the rate borne by the Securities which has become due
otherwise than by such declaration of acceleration; (b) the rescission would not
conflict with any judgment or decree of a court of competent jurisdiction; and
(c) all Events of Default, other than the nonpayment of principal of, premium,
if any, and interest on the Securities that has become due solely by such
declaration of acceleration, have been cured or waived.

          The Holders of not less than a majority in aggregate principal amount
of the outstanding Securities may on behalf of the holders of all the Securities
waive any past defaults under this Indenture, except (i) a default in the
payment of the principal of, premium, if any, or interest on any Security, (ii)
a default in respect of a covenant or provision which under this Indenture
cannot be modified or amended without the consent of the Holder of each Security
Outstanding, and (iii) as limited by Section 10.21 hereof.

          Section 5.3 Collection of Indebtedness and Suits for Enforcement by
Trustee.  The Company covenants that if

          (a) default is made in the payment of any installment of interest on
any Security when such interest becomes due and payable and such default
continues for a period of 30 days, or

          (b) default is made in the payment of the principal of (or premium, if
any, on) any Security at the Maturity thereof or with respect to any Security
required to have been purchased by the Company on the Change of Control Purchase
Date or the Net Proceeds Payment Date pursuant to a Change of Control Offer or a
Net Proceeds Offer, as applicable,

the Company will, upon demand of the Trustee, pay to the Trustee for the benefit
of the Holders of such Securities, the whole amount then due and payable on such
Securities for principal (and premium, if any) and interest, and interest on any
overdue principal (and premium, if any) and, to the extent that payment of such
interest shall be legally enforceable, upon any overdue installment of interest,
at the rate borne by the Securities, and, in addition thereto, such further
amount as shall be sufficient to cover the costs and expenses of collection,
including the reasonable compensation, expenses, disbursements and advances of
the Trustee, its agents and counsel.

          If the Company fails to pay such amounts forthwith upon such demand,
the Trustee, in its own name as trustee of an express trust, may institute a
judicial proceeding for the collection of the sums so due and unpaid, may
prosecute such proceeding to judgment or final decree and may enforce the same
against the Company or any other obligor upon the Securities and collect the
moneys adjudged or decreed to be payable in the manner provided by law out of
the Property of the Company or any other obligor upon the Securities, wherever
situated.

          If an Event of Default occurs and is continuing, the Trustee may in
its discretion proceed to protect and enforce its rights and the rights of the
Holders by such appropriate judicial proceedings as the Trustee shall deem most
effectual to protect and enforce any such rights, whether

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<PAGE>
 
for the specific enforcement of any covenant or agreement in this Indenture or
in aid of the exercise of any power granted herein, or to enforce any other
proper remedy.

          Section 5.4 Trustee May File Proofs of Claim.  In case of the pendency
of any receivership, insolvency, liquidation, bankruptcy, reorganization,
arrangement, adjustment, composition or other judicial proceeding relative to
the Company, the Subsidiary Guarantors or any other obligor upon the Securities
or the Property of the Company, the Subsidiary Guarantors or of such other
obligor or their creditors, the Trustee (irrespective of whether the principal
of the Securities shall then be due and payable as therein expressed or by
declaration or otherwise and irrespective of whether the Trustee shall have made
any demand on the Company, the Subsidiary Guarantors or such other obligor for
the payment of overdue principal, premium, if any, or interest) shall be
entitled and empowered, by intervention in such proceeding or otherwise,

          (a) to file and prove a claim for the whole amount of principal (and
premium, if any) and interest owing and unpaid in respect of the Securities and
to file such other papers or documents and take any other actions including
participation as a full member of any creditor or other committee as may be
necessary or advisable in order to have the claims of the Trustee (including any
claim for the reasonable compensation, expenses, disbursements and advances of
the Trustee, its agents and counsel) and of the Holders allowed in such judicial
proceeding, and

          (b) to collect and receive any moneys or other Property payable or
deliverable on any such claims and to distribute the same;

and any custodian, receiver, assignee, trustee, liquidator, sequestrator or
similar official in any such judicial proceeding is hereby authorized by each
Holder to make such payments to the Trustee and, in the event that the Trustee
shall consent to the making of such payments directly to the Holders, to pay the
Trustee any amount due to it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any other
amounts due the Trustee under Section 6.6 hereof.

          Nothing herein contained shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Securities
or the Subsidiary Guarantees or the rights of any Holder thereof, or to
authorize the Trustee to vote in respect of the claim of any Holder in any such
proceeding.

          Section 5.5 Trustee May Enforce Claims Without Possession of
Securities.  All rights of action and claims under this Indenture or the
Securities or the Subsidiary Guarantees may be prosecuted and enforced by the
Trustee without the possession of any of the Securities or the production
thereof in any proceeding relating thereto, and any such proceeding instituted
by the Trustee shall be brought in its own name and as trustee of an express
trust, and any recovery of judgment shall, after provision for the payment of
the reasonable compensation, expenses,

                                       69
<PAGE>
 
disbursements and advances of the Trustee, its agents and counsel, be for the
ratable benefit of the Holders of the Securities in respect of which such
judgment has been recovered.

          Section 5.6 Application of Money Collected.  Any money collected by
the Trustee pursuant to this Article shall be applied in the following order, at
the date or dates fixed by the Trustee and, in the case of the distribution of
such money on account of principal (or premium, if any) or interest, upon
presentation of the Securities and the notation thereon of the payment if only
partially paid and upon surrender thereof if fully paid:

          FIRST:  To the payment of all amounts due the Trustee under Section
     6.6 hereof,

          SECOND:  To the payment of the amounts then due and unpaid for
     principal of (and premium, if any, on,) and interest on the Securities in
     respect of which or for the benefit of which such money has been collected,
     ratably, without preference or priority of any kind, according to the
     amounts due and payable on such Securities for principal (and premium, if
     any) and interest, respectively; and

          THIRD:  The balance, if any, to the Company.

     Section 5.7 Limitation on Suits. No Holder of any Securities shall have any
right to institute any proceeding, judicial or otherwise, with respect to this
Indenture, or for the appointment of a receiver or trustee, or for any other
remedy hereunder, unless

          (a) such Holder has previously given written notice to the Trustee of
a continuing Event of Default;

          (b) the Holders of not less than 25% in aggregate principal amount of
the Outstanding Securities shall have made written request to the Trustee to
institute proceedings in respect of such Event of Default in its own name as
Trustee hereunder;

          (c) such Holder or Holders have offered to the Trustee reasonable
indemnity against the costs, expenses and liabilities to be incurred in
compliance with such request;

          (d) the Trustee for 60 days after its receipt of such notice, request
and offer of indemnity has failed to institute any such proceeding; and

          (e) no direction inconsistent with such written request has been given
to the Trustee during such 60-day period by the Holders of a majority or more in
aggregate principal amount of the Outstanding Securities;

it being understood and intended that no one or more Holders shall have any
right in any manner whatever by virtue of, or by availing of, any provision of
this Indenture to affect, disturb or prejudice the rights of any other Holders,
or to obtain or to seek to obtain priority or preference over any other

                                       70
<PAGE>
 
Holders or to enforce any right under this Indenture, except in the manner
herein provided and for the equal and ratable benefit of all the Holders.

          Section 5.8 Unconditional Right of Holders to Receive Principal,
Premium and Interest.  Notwithstanding any other provision in this Indenture,
the Holder of any Security shall have the right, which is absolute and
unconditional, to receive payment, as provided herein (including, if applicable,
Article XII hereof) and in such Security of the principal of (and premium, if
any, on) and (subject to Section 3.9 hereof) interest on, such Security on the
respective Stated Maturities expressed in such Security (or, in the case of
redemption, on the Redemption Date) and to institute suit for the enforcement of
any such payment, and such rights shall not be impaired without the consent of
such Holder.

          Section 5.9 Restoration of Rights and Remedies.  If the Trustee or any
Holder has instituted any proceeding to enforce any right or remedy under this
Indenture and such proceeding has been discontinued or abandoned for any reason,
or has been determined adversely to the Trustee or to such Holder, then and in
every such case, subject to any determination in such proceeding, the Company,
the Subsidiary Guarantors, the Trustee and the Holders shall be restored
severally and respectively to their former positions hereunder and thereunder
and all rights and remedies of the Trustee and the Holders shall continue as
though no such proceeding had been instituted.

          Section 5.10 Rights and Remedies Cumulative.  Except as otherwise
provided with respect to the replacement or payment of mutilated, destroyed,
lost or stolen Securities in the last paragraph of Section 3.8 hereof, no right
or remedy herein conferred upon or reserved to the Trustee or to the Holders is
intended to be exclusive of any other right or remedy, and every right and
remedy shall, to the extent permitted by law, be cumulative and in addition to
every other right and remedy given hereunder or now or hereafter existing at law
or in equity or otherwise.  The assertion or employment of any right or remedy
hereunder, or otherwise, shall not prevent the concurrent assertion or
employment of any other appropriate right or remedy.

          Section 5.11 Delay or Omission Not Waiver. No delay or omission of the
Trustee or of any Holder of any Security to exercise any right or remedy
accruing upon any Event of Default shall impair any such right or remedy or
constitute a waiver of any such Event of Default or an acquiescence therein.
Every right and remedy given by this Article or by law to the Trustee or to the
Holders may be exercised from time to time, and as often as may be deemed
expedient, by the Trustee or by the Holders, as the case may be.

          Section 5.12 Control by Holders.  The Holders of not less than a
majority in principal amount of the Outstanding Securities shall have the right
to direct the time, method and place of conducting any proceeding for any remedy
available to the Trustee, or exercising any trust or power conferred on the
Trustee, provided that

          (a) such direction shall not be in conflict with any rule of law or
with this Indenture,

                                       71
<PAGE>
 
          (b) the Trustee may take any other action deemed proper by the
Trustee which is not inconsistent with such direction, and

          (c) the Trustee need not take any action which might involve it in
personal liability or be unduly prejudicial to the Holders not joining therein.

     Section 5.13 Waiver of Past Defaults.  The Holders of not less than a
majority in principal amount of the Outstanding Securities may on behalf of the
Holders of all the Securities waive any existing Default or Event of Default
hereunder and its consequences, except a Default or Event of Default

          (a) in respect of the payment of the principal of (or premium, if
any, on) or interest on any Security, or

          (b) in respect of a covenant or provision hereof which under Article
IX hereof cannot be modified or amended without the consent of the Holder of
each Outstanding Security affected.

          Upon any such waiver, such Default or Event of Default shall cease to
exist for every purpose under this Indenture, but no such waiver shall extend to
any subsequent or other Default or Event of Default or impair any right
consequent thereon.

     Section 5.14 Waiver of Stay, Extension or Usury Laws.  Each of the
Company and the Subsidiary Guarantors covenants (to the extent that each may
lawfully do so) that it will not at any time insist upon, plead or in any manner
whatsoever claim or take the benefit or advantage of, any stay, extension, or
usury law or other law, which would prohibit or forgive the Company or any
Subsidiary Guarantor from paying all or any portion of the principal of
(premium, if any, on) and/or interest on the Securities as contemplated herein,
wherever enacted, now or at any time hereafter in force, or which may affect the
covenants or the performance of this Indenture; and (to the extent that it may
lawfully do so) each of the Company and the Subsidiary Guarantors hereby
expressly waives all benefit or advantage of any such law, and covenants that it
will not hinder, delay or impede the execution of any power herein granted to
the Trustee, but will suffer and permit the execution of every such power as
though no such law had been enacted.


                                  ARTICLE VI

                                  THE TRUSTEE
                                  -----------

     Section 6.1 Notice of Defaults.  Within 60 days after the occurrence of any
Default hereunder, the Trustee shall transmit in the manner and to the extent
provided in TIA Section 313(c), notice of such Default hereunder known to the
Trustee, unless such Default shall have been cured or waived; provided, however,
that, except in the case of a Default in the payment of the principal

                                       72
<PAGE>
 
of (or premium, if any, on) or interest on any Security, the Trustee shall be
protected in withholding such notice if and so long as the board of directors,
the executive committee or a trust committee of directors and/or Responsible
Officers of the Trustee in good faith determines that the withholding of such
notice is in the interest of the Holders; and provided, further, that in the
case of any Default of the character specified in Section 5.1(e) hereof, no such
notice to Holders shall be given until at least 60 days after the occurrence
thereof.

     Section 6.2 Certain Rights and Duties of Trustee.

          (a) If an Event of Default has occurred and is continuing, the Trustee
shall exercise such of the rights and powers vested in it by this Indenture, and
use the same degree of care and skill in its exercise, as a prudent Person would
exercise or use under the circumstances in the conduct of his or her own
affairs.

          (b) Except during the continuance of an Event of Default:

              (i) The Trustee need perform only those duties that are
     specifically set forth in this Indenture and the TIA and no others, and no
     implied covenants or obligations shall be read into this Indenture against
     the Trustee. To the extent of any conflict between the duties of the
     Trustee hereunder and under the TIA, the TIA shall control.

              (ii) In the absence of bad faith on its part, the Trustee may
     conclusively rely, as to the truth of the statements and the correctness of
     the opinions expressed therein, upon certificates or opinions furnished to
     the Trustee and conforming to the requirements of this Indenture.  However,
     the Trustee shall examine the certificates and opinions to determine
     whether or not they conform to the requirements of this Indenture (but need
     not confirm or investigate the accuracy of mathematical calculations or
     other facts stated therein).

          (c) The Trustee may not be relieved from liabilities for its own
negligent action, its own negligent failure to act, or its own willful
misconduct, except that:

              (i) this paragraph does not limit the effect of paragraph (b) of
     this Section;

              (ii) the Trustee shall not be liable for any error of judgment
     made in good faith by a Responsible Officer, unless it is proved that the
     Trustee was negligent in ascertaining the pertinent facts; and

              (iii) the Trustee shall not be liable with respect to any action
     it takes or omits to take in good faith in accordance with a direction
     received by it pursuant to Section 5.12 hereof.

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<PAGE>
 
          (d) Whether or not therein expressly so provided, every provision of
this Indenture that in any way relates to the Trustee is subject to paragraphs
(a), (b), and (c) of this Section.

          (e) The Trustee shall not be liable for interest on any money received
by it except as the Trustee may agree in writing with the Company. Money held in
trust by the Trustee need not be segregated from other funds except to the
extent required by law.

          (f) Subject to the provisions of TIA Sections 315(a) through 315(d):

              (i) the Trustee may rely and shall be protected in acting or
     refraining from acting upon any resolution, certificate, statement,
     instrument, opinion, report, notice, request, direction, consent, order,
     bond, debenture, note, other evidence of indebtedness or other paper or
     document believed by it to be genuine and to have been signed or presented
     by the proper party or parties;

              (ii) any request or direction of the Company mentioned herein
     shall be sufficiently evidenced by a Company Request or Company Order and
     any resolution of the Board of Directors may be sufficiently evidenced by a
     Board Resolution;

              (iii) whenever in the administration of this Indenture the Trustee
     shall deem it desirable that a matter be proved or established prior to
     taking, suffering or omitting any action hereunder, the Trustee (unless
     other evidence be herein specifically prescribed) may, in the absence of
     bad faith on its part, rely upon an Officers' Certificate;

              (iv) the Trustee may consult with counsel and the written advice
     of such counsel or any Opinion of Counsel shall be full and complete
     authorization and protection in respect of any action taken, suffered or
     omitted by it hereunder in good faith and in reliance thereon;

              (v) the Trustee shall be under no obligation to exercise any of
     the rights or powers vested in it by this Indenture at the request or
     direction of any of the Holders pursuant to this Indenture, unless such
     Holders shall have offered to the Trustee reasonable security or indemnity
     against the costs, expenses and liabilities which might be incurred by it
     in compliance with such request or direction;

              (vi) the Trustee shall not be bound to make any investigation into
     the facts or matters stated in any resolution, certificate, statement,
     instrument, opinion, report, notice, request, direction, consent, order,
     bond, debenture, note, other evidence of indebtedness or other paper or
     document, but the Trustee, in its discretion, may make such further inquiry
     or investigation into such facts or matters as it may see fit, and, if the
     Trustee shall determine to make such further inquiry or investigation, it
     shall be entitled to examine the books, records and premises of the
     Company, personally or by agent or attorney;

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<PAGE>
 
              (vii) the Trustee may execute any of the trusts or powers
     hereunder or perform any duties hereunder either directly or by or through
     agents or attorneys and the Trustee shall not be responsible for any
     misconduct or negligence on the part of any agent or attorney appointed
     with due care by it hereunder; and

              (viii) the Trustee shall not be liable for any action taken,
     suffered or omitted by it in good faith and believed by it to be authorized
     or within the discretion or rights or powers conferred upon it by this
     Indenture.

          (g) The Trustee shall not be required to advance, expend or risk its
own funds or otherwise incur any financial liability in the performance of any
of its duties hereunder, or in the exercise of any of its rights or powers if it
shall have reasonable grounds for believing that repayment of such funds or
adequate indemnity against such risk or liability is not reasonably assured to
it.

     Section 6.3 Trustee Not Responsible for Recitals or Issuance of Securities.
The recitals contained herein and in the Securities and the notations of
Subsidiary Guarantees thereon, except for the Trustee's certificates of
authentication, shall be taken as the statements of the Company or the
Subsidiary Guarantors, as the case may be, and the Trustee assumes no
responsibility for their correctness.  The Trustee makes no representations as
to the validity or sufficiency of this Indenture or of the Securities, except
that the Trustee represents that it is duly authorized to execute and deliver
this Indenture, authenticate the Securities and perform its obligations
hereunder, and that the statements made by it in a Statement of Eligibility and
Qualification on Form T-1 supplied to the Company are true and accurate, subject
to the qualifications set forth herein.  The Trustee shall not be accountable
for the use or application by the Company of Securities or the proceeds thereof.

     Section 6.4 May Hold Securities. The Trustee, any Paying Agent, any
Security Register or any other agent of the Company, any Subsidiary Guarantor or
of the Trustee, in its individual or any other capacity, may become the owner or
pledgee of Securities and, subject to TIA Sections 310(b) and 311, may otherwise
deal with the Company and the Subsidiary Guarantors with the same rights it
would have if it were not the Trustee, Paying Agent, Security Registrar or such
other agent.

     Section 6.5 Money Held in Trust.  Money held by the Trustee in trust
hereunder need not be segregated from other funds except to the extent required
by law.  The Trustee shall be under no liability for interest on any money
received by it hereunder except as otherwise agreed with the Company or any
Subsidiary Guarantor.

     Section 6.6 Compensation and Reimbursement.  The Company agrees:

          (a) to pay to the Trustee from time to time reasonable compensation
for all services rendered by it hereunder (which compensation shall not be
limited by any provision of law in regard to the compensation of a trustee of an
express trust);

                                       75
<PAGE>
 
          (b) except as otherwise expressly provided herein, to reimburse the
Trustee upon its request for all reasonable expenses, disbursements and advances
incurred or made by the Trustee in accordance with any provision of this
Indenture (including the reasonable compensation and the expenses and
disbursements of its agents and counsel, except any such expense, disbursement
or advance as may be attributable to the Trustee's negligence or bad faith); and

          (c) to indemnify the Trustee for, and to hold it harmless against, any
loss, liability or expense incurred without negligence or bad faith on its part,
arising out of or in connection with the acceptance or administration of this
trust, including the costs and expenses of defending itself against any claim or
liability in connection with the exercise or performance of any of its powers or
duties hereunder or  in connection with enforcing this indemnification
provision.

          The obligations of the Company under this Section 6.6 to compensate
the Trustee, to pay or reimburse the Trustee for expenses, disbursements and
advances and to indemnify and hold harmless the Trustee shall constitute
additional indebtedness hereunder and shall survive the satisfaction and
discharge of this Indenture or any other termination under any Insolvency or
Liquidation Proceeding.  As security for the performance of such obligations of
the Company, the Trustee shall have a claim and lien prior to the Securities
upon all property and funds held or collected by the Trustee as such, except
funds held in trust for payment of principal of (and premium, if any, on) or
interest on particular Securities.  Such lien shall survive the satisfaction and
discharge of this Indenture or any other termination under any Insolvency or
Liquidation Proceeding.

          When the Trustee incurs expenses or renders services after the
occurrence of an Event of Default specified in paragraphs (i) or (j) of Section
5.1 of this Indenture, such expenses and the compensation for such services are
intended to constitute expenses of administration under any Insolvency or
Liquidation Proceeding.

     Section 6.7 Corporate Trustee Required; Eligibility.  There shall at all
times be a Trustee hereunder which shall be eligible to act as Trustee under TIA
Section 310(a)(1) and shall have a combined capital and surplus of at least
$50,000,000.  If such corporation publishes reports of condition at least
annually, pursuant to law or to the requirements of federal, state, territorial
or District of Columbia supervising or examining authority, then for the
purposes of this Section 6.7, the combined capital and surplus of such
corporation shall be deemed to be its combined capital and surplus as set forth
in its most recent report of condition so published.  If at any time the Trustee
shall cease to be eligible in accordance with the provisions of this Section, it
shall resign immediately in the manner and with the effect hereinafter specified
in this Article.

     Section 6.8 Conflicting Interests.  The Trustee shall comply with the
provisions of Section 310(b) of the Trust Indenture Act.

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<PAGE>
 
     Section 6.9 Resignation and Removal; Appointment of Successor.

          (a) No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee in accordance with the
applicable requirements of Section 6.10 hereof.

          (b) The Trustee may resign at any time by giving written notice
thereof to the Company. If the instrument of acceptance by a successor Trustee
required by Section 6.10 hereof shall not have been delivered to the Trustee
within 30 days after the giving of such notice of resignation, the resigning
Trustee may petition any court of competent jurisdiction for the appointment of
a successor Trustee.

          (c) The Trustee may be removed at any time by Act of the Holders of
not less than a majority in principal amount of the Outstanding Securities,
delivered to the Trustee and to the Company.

          (d) If at any time:

              (i) the Trustee shall fail to comply with the provisions of TIA
     Section 310(b) after written request therefor by the Company or by any
     Holder who has been a bona fide Holder of a Security for at least six
     months, or

              (ii) the Trustee shall cease to be eligible under Section 6.7
     hereof and shall fail to resign after written request therefor by the
     Company or by any Holder who has been a bona fide Holder of a Security for
     at least six months, or

              (iii) the Trustee shall become incapable of acting or shall be
     adjudged a bankrupt or insolvent or a receiver of the Trustee or of its
     property shall be appointed or any public officer shall take charge or
     control of the Trustee or of its property or affairs for the purpose of
     rehabilitation, conservation or liquidation,

then, in any such case, (i) the Company, by a Board Resolution, may remove the
Trustee, or (ii) subject to TIA Section 315(e), any Holder who has been a bona
fide Holder of a Security for at least six months may, on behalf of himself and
all others similarly situated, petition any court of competent jurisdiction for
the removal of the Trustee and the appointment of a successor Trustee.

          (e) If the Trustee shall resign, be removed or become incapable of
acting, or if a vacancy shall occur in the office of Trustee for any cause, the
Company, by a Board Resolution, shall promptly appoint a successor Trustee.  If,
within one year after such resignation, removal or incapability, or the
occurrence of such vacancy, a successor Trustee shall be appointed by Act of the
Holders of a majority in principal amount of the Outstanding Securities
delivered to the Company and the retiring Trustee, the successor Trustee so
appointed shall, forthwith upon its acceptance of such appointment, become the
successor Trustee and supersede the successor Trustee appointed by 

                                       77
<PAGE>
 
the Company. If no successor Trustee shall have been so appointed by the Company
or the Holders and accepted appointment in the manner hereinafter provided, any
Holder who has been a bona fide Holder of a Security for at least six months
may, on behalf of himself and all others similarly situated, petition any court
of competent jurisdiction for the appointment of a successor Trustee. The
evidence of such successorship may, but need not be, evidenced by a supplemental
indenture.

          (f) The Company shall give notice of each resignation and each removal
of the Trustee and each appointment of a successor Trustee to the Holders of
Securities in the manner provided for in Section 15.5 hereof.  Each notice shall
include the name of the successor Trustee and the address of its Corporate Trust
Office.

     Section 6.10 Acceptance of Appointment by Successor.  Every successor
Trustee appointed hereunder shall execute, acknowledge and deliver to the
Company and to the retiring Trustee an instrument accepting such appointment,
and thereupon the resignation or removal of the retiring Trustee shall become
effective and such successor Trustee, without any further act, deed or
conveyance, shall become vested with all the rights, powers, trusts and duties
of the retiring Trustee, but, on request of the Company or the successor
Trustee, such retiring Trustee shall, upon payment of all amounts due it under
Section 6.6 hereof, execute and deliver an instrument transferring to such
successor Trustee all the rights, powers and trusts of the retiring Trustee and
shall duly assign, transfer and deliver to such successor Trustee all property
and money held by such retiring Trustee hereunder.  Upon request of any such
successor Trustee, the Company shall execute any and all instruments for more
fully and certainly vesting in and confirming to such successor Trustee all such
rights, powers and trusts.

          No successor Trustee shall accept its appointment unless at the time
of such acceptance such successor Trustee shall be qualified and eligible under
this Article.

     Section 6.11 Merger, Conversion, Consolidation or Succession to Business.
Any corporation into which the Trustee may be merged or converted or with which
it may be consolidated, or any corporation resulting from any merger, conversion
or consolidation to which the Trustee shall be a party, or any corporation
succeeding to all or substantially all of the corporate trust business of the
Trustee, shall be the successor of the Trustee hereunder, provided such
corporation shall be otherwise qualified and eligible under this Article,
without the execution or filing of any paper or any further act on the part of
any of the parties hereto. In case any Securities shall have been authenticated,
but not delivered, by the Trustee then in office, any successor by merger,
conversion or consolidation to such authenticating Trustee may adopt such
authentication and deliver the Securities so authenticated with the same effect
as if such successor Trustee had itself authenticated such Securities; and in
case at that time any of the Securities shall not have been authenticated, any
successor Trustee may authenticate such Securities either in the name of any
predecessor hereunder or in the name of the successor Trustee; provided,
however, that the right to adopt the certificate of authentication of any
predecessor Trustee or to authenticate Securities in the name of any predecessor
Trustee shall apply only to its successor or successors by merger, conversion or
consolidation.

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<PAGE>
 
     Section 6.12 Preferential Collection of Claims Against Company.  If and
when the Trustee shall be or become a creditor of the Company (or any other
obligor under the Securities), the Trustee shall be subject to the provisions of
the Trust Indenture Act regarding the collection of claims against the Company
or any such other obligor.


                                  ARTICLE VII

                     HOLDERS' LISTS AND REPORTS BY TRUSTEE
                     -------------------------------------

     Section 7.1 Disclosure of Names and Addresses of Holders.  Every Holder of
Securities, by receiving and holding the same, agrees with the Company, the
Subsidiary Guarantors, the Security Registrar and the Trustee that none of the
Company, the Subsidiary Guarantors, the Security Registrar or the Trustee, or
any agent of any of them, shall be held accountable by reason of the disclosure
of any such information as to the names and addresses of the Holders in
accordance with TIA Section 312, regardless of the source from which such
information was derived, and that the Trustee shall not be held accountable by
reason of mailing any material pursuant to a request made under TIA Section
312(b).

     Section 7.2 Reports By Trustee.  Within 60 days after May 15 of each year
commencing with May 15, 1999, the Trustee shall transmit by mail to the Holders,
as their names and addresses appear in the Security Register, a brief report
dated as of such May 15 in accordance with and to the extent required under TIA
Section 313(a).  The Trustee shall also comply with TIA Sections 313(b) and
313(c).

     The Company shall promptly notify the Trustee in writing if the Securities
become listed on any stock exchange or automatic quotation system.

     A copy of each Trustee's report, at the time of its mailing to Holders of
Securities, shall be mailed to the Company and filed with the Commission and
each stock exchange, if any, on which the Securities are listed.


                                 ARTICLE VIII

             CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER OR LEASE
             ----------------------------------------------------

     Section 8.1 Company May Consolidate, etc., Only on Certain Terms.  The
Company (A) will not, in any single transaction or series of related
transactions, merge or consolidate with or into any other Person, or sell,
assign, convey, transfer, lease or otherwise dispose of all or substantially all
of its Properties and assets to any Person or group of Affiliated Persons, and
(B) shall not permit any of its Restricted Subsidiaries to enter into any such
transaction or series of transactions if such transaction or series of
transactions by Restricted Subsidiaries, in the aggregate, would result in a

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<PAGE>
 
sale, assignment, conveyance, transfer, lease or other disposition of all or
substantially all of the Properties and assets of the Company and its Restricted
Subsidiaries on a consolidated basis to any other Person or group of Affiliated
Persons, unless at the time and after giving effect thereto (i) either (a) if
the transaction or transactions is a merger or consolidation, the Company or a
Restricted Subsidiary, as the case may be, shall be the surviving Person of such
merger or consolidation, or (b) the Person (if other than the Company or a
Restricted Subsidiary, as the case may be) formed by such consolidation or into
which the Company or such Restricted Subsidiary is merged or to which the
Properties and assets of the Company or such Restricted Subsidiary, as the case
may be, are sold, assigned, conveyed, transferred, leased or otherwise disposed
of (any such surviving Person or transferee Person being the "Surviving Entity")
shall be a corporation organized and existing under the laws of the United
States of America, any state thereof or the District of Columbia and shall, in
either case, expressly assume by a supplemental indenture to this Indenture
executed and delivered to the Trustee, in form satisfactory to the Trustee, all
the obligations of the Company for the due and punctual payment of the principal
of (and premium, if any, on) and interest on all the Securities and the
performance and observance of every covenant of this Indenture on the part of
the Company, to be performed or observed, and this Indenture shall remain in
full force and effect; (ii) immediately before and immediately after giving
effect to such transaction or series of transactions on a pro forma basis (and
treating any Indebtedness not previously an obligation of the Company or any of
its Restricted Subsidiaries which becomes the obligation of the Company or any
of its Restricted Subsidiaries in connection with or as a result of such
transaction or transactions as having been incurred at the time of such
transaction or transactions), no Default or Event of Default shall have occurred
and be continuing; (iii) except in the case of the consolidation or merger of
any Restricted Subsidiary with or into the Company, immediately after giving
effect to such transaction or transactions on a pro forma basis, the
Consolidated Net Worth of the Company (or the Surviving Entity if the Company is
not the continuing obligor under this Indenture) is at least equal to the
Consolidated Net Worth of the Company immediately before such transaction or
transactions; (iv) except in the case of the consolidation or merger of any
Restricted Subsidiary with or into the Company or any Wholly Owned Restricted
Subsidiary, immediately before and immediately after giving effect to such
transaction or transactions on a pro forma basis (on the assumption that the
transaction or transactions occurred on the first day of the period of four full
fiscal quarters ending immediately prior to the consummation of such transaction
or transactions, with the appropriate adjustments with respect to the
transaction or transactions being included in such pro forma calculation), the
Company (or the Surviving Entity if the Company is not the continuing obligor
under this Indenture) could incur $1.00 of additional Indebtedness (excluding
Permitted Indebtedness) pursuant to Section 10.12 hereof; (v) if the Company is
not the Surviving Entity, each Subsidiary Guarantor, unless it is the other
party to the transactions described above, shall have by supplemental indenture
to this Indenture confirmed that its Subsidiary Guarantee shall apply to such
Person's obligations under this Indenture and the Securities; and (vi) if any of
the Properties or assets of the Company or any of its Restricted Subsidiaries
would upon such transaction or series of related transactions become subject to
any Lien (other than a Permitted Lien), the creation and imposition of such Lien
shall have been in compliance with Section 10.15 hereof.

                                       80
<PAGE>
 
          In connection with any consolidation, merger, sale, assignment,
conveyance, transfer, lease or other disposition contemplated hereby, the
Company shall deliver, or cause to be delivered, to the Trustee, in form and
substance reasonably satisfactory to the Trustee, an Officers' Certificate
stating that such consolidation, merger, sale, assignment, conveyance, transfer,
lease or other disposition and any supplemental indenture in respect thereto
comply with the requirements under this Indenture and an Opinion of Counsel
stating that the requirements of clause (i) of the preceding paragraph have been
complied with.

     Section 8.2 Successor Substituted.   Upon any consolidation of the Company
with or merger of the Company with or into any other Person or any sale,
assignment, conveyance, transfer, lease or other disposition of all or
substantially all of the Properties of the Company to any Person in accordance
with Section 8.1 hereof, the successor Person formed by such consolidation or
into which the Company is merged or to which such sale, assignment, conveyance.
transfer or other disposition (other than by lease) is made shall succeed to,
and be substituted for, and may exercise every right and power of, the Company
under this Indenture with the same effect as if such successor Person had been
named as the Company herein, and in the event of any such sale, assignment,
lease, conveyance, transfer or other disposition, the Company (which term shall
for this purpose mean the Person named as the "Company" in the first paragraph
of this Indenture or any successor Person which shall theretofore become such in
the manner described in Section 8.1 hereof), except in the case of a lease,
shall be discharged of all obligations and covenants under this Indenture and
the Securities and the Company may be dissolved and liquidated and such
dissolution and liquidation shall not cause a Change of Control under clause (e)
of the definition thereof to occur unless the merger, or the sale, assignment,
lease, conveyance, transfer or other disposition of all or substantially all of
the Properties of the Company to any Person otherwise results in a Change of
Control.


                                  ARTICLE IX

                            SUPPLEMENTAL INDENTURES
                            -----------------------

     Section 9.1 Supplemental Indentures Without Consent of Holders. Without the
consent of any Holders, the Company, the Subsidiary Guarantors and the Trustee,
at any time and from time to time, may enter into one or more indentures
supplemental hereto, in form satisfactory to the Trustee, for any of the
following purposes:

          (a) to evidence the succession of another Person to the Company and
the assumption by any such successor of the covenants of the Company contained
herein and in the Securities; or

          (b) to add to the covenants of the Company for the benefit of the
Holders or to surrender any right or power herein conferred upon the Company; or

          (c) to add any additional Events of Default; or

                                       81
<PAGE>
 
          (d) to evidence and provide for the acceptance of appointment
hereunder by a successor Trustee pursuant to the requirements of Sections 6.9
and 6.10 hereof; or

          (e) to cure any ambiguity, to correct or supplement any provision
herein which may be defective or inconsistent with any other provision herein;
or

          (f) to secure the Securities pursuant to the requirements of Section
10.15 hereof or otherwise; or

          (g) to add any Person as a Subsidiary Guarantor as provided in
Sections 10.13 and 13.1 hereof or as contemplated by the definition of
"Permitted Subsidiary Indebtedness" or to evidence the succession of another
Person to any Guarantor and the assumption by any such successor of the
covenants and agreements of such Subsidiary Guarantor contained herein, in the
Securities and in the Subsidiary Guarantee; or

          (h) to release a Subsidiary Guarantor from its Guarantee pursuant to
Sections 10.13 and 13.3 hereof; or

          (i) to provide for uncertificated Securities in addition to or in
place of certificated Securities; or

          (j) to make any other provisions with respect to matters or questions
arising under this Indenture; provided that such action shall not adversely
affect the interests of the Holders in any material respect.

     Section 9.2 Supplemental Indenture with Consent of Holders. With the
consent of the Holders of not less than a majority in principal amount of the
Outstanding Securities, by Act of said Holders delivered to the Company and the
Trustee, the Company, when authorized by a Board Resolution, the Subsidiary
Guarantors, when authorized by a Board Resolution, and the Trustee may enter
into an indenture or indentures supplemental hereto for the purpose of adding
any provisions to or changing in any manner or eliminating any of the provisions
of this Indenture or of modifying in any manner the rights of the Holders under
this Indenture; provided, however, that no such supplemental indenture shall,
without the consent of the Holder of each Outstanding Security affected thereby:

          (a) change the Stated Maturity of the principal of, or any installment
of interest on, any Security, or reduce the principal amount thereof or the rate
of interest thereon or any premium payable upon the redemption thereof, or
change the place, coin or currency in which any Security or any premium or the
interest thereon is payable, or impair the right to institute suit for the
enforcement of any such payment after the Stated Maturity thereof (or, in the
case of redemption, on or after the Redemption Date); or

                                       82
<PAGE>
 
          (b) reduce the percentage of aggregate principal amount of the
Outstanding Securities, the consent of whose Holders is required for any such
supplemental indenture, or the consent of whose Holders is required for any
waiver of compliance with certain provisions of this Indenture or certain
defaults hereunder and their consequences provided for in this Indenture; or

          (c) modify any of the provisions of this Section or Sections 5.13 and
10.21 hereof, except to increase any such percentage or to provide that certain
other provisions of this Indenture cannot be modified or waived without the
consent of the Holder of each Outstanding Security affected thereby; or

          (d) modify Section 10.13(a) hereof or any provisions of this Indenture
relating to the Subsidiary Guarantees in a manner adverse to the Holders
thereof; or

          (e) amend, change or modify the obligation of the Company to make and
consummate a Change of Control Offer in the event of a Change of Control, or to
make and consummate a Net Proceeds Offer with respect to any Asset Sale or
modify any of the provisions or definitions with respect thereto.

     It shall not be necessary for any Act of the Holders under this Section to
approve the particular form of any proposed supplemental indenture, but it shall
be sufficient if such Act shall approve the substance thereof.

     Section 9.3 Execution of Supplemental Indentures. In executing, or
accepting the additional trusts created by, any supplemental indenture permitted
by this Article or the modifications thereby of the trusts created by this
Indenture, the Trustee shall be entitled to receive, and shall be fully
protected in relying upon, an Opinion of Counsel stating that the execution of
such supplemental indenture is authorized or permitted by this Indenture. The
Trustee may, but shall not be obligated to, enter into any such supplemental
indenture which affects the Trustee's own rights, duties or immunities under
this Indenture or otherwise.

     Section 9.4 Effect of Supplemental Indentures.  Upon the execution of any
supplemental indenture under this Article, this Indenture shall be modified in
accordance therewith, and such supplemental indenture shall form a part of this
Indenture for all purposes, and every Holder of Securities theretofore or
thereafter authenticated and delivered hereunder shall be bound thereby.

     Section 9.5 Conformity With Trust Indenture Act.  Every supplemental
indenture executed pursuant to this Article shall conform to the requirements of
the Trust Indenture Act as then in effect.

     Section 9.6 Reference in Securities to Supplemental Indentures.  Securities
authenticated and delivered after the execution of any supplemental indenture
pursuant to this Article may, and shall if required by the Trustee, bear a
notation in form approved by the Trustee as to any matter provided for in such
supplemental indenture.  If the Company shall so determine, new Securities so

                                       83
<PAGE>
 
modified as to conform, in the opinion of the Trustee and the Company, to any
such supplemental indenture may be prepared and executed by the Company, with
the notations of Subsidiary Guarantees thereon executed by the Subsidiary
Guarantors, and authenticated and delivered by the Trustee in exchange for
Outstanding Securities.

     Section 9.7 Notice of Supplemental Indentures. Promptly after the execution
by the Company and the Trustee of any supplemental indenture pursuant to the
provisions of Section 9.2 hereof, the Company shall give notice thereof to the
Holders of each Outstanding Security affected, in the manner provided for in
Section 15.5 hereof, setting forth in general terms the substance of such
supplemental indenture.


                                   ARTICLE X

                                   COVENANTS
                                   ---------

     Section 10.1 Payment of Principal, Premium, if any, and Interest. The
Company covenants and agrees for the benefit of the Holders that it will duly
and punctually pay the principal of (and premium, if any, on) and interest on
the Securities in accordance with the terms of the Securities and this
Indenture.

     Section 10.2 Maintenance of Office or Agency. The Company shall maintain in
the Borough of Manhattan, The City of New York, an office or agency where
Securities may be presented or surrendered for payment, where Securities may be
surrendered for registration of transfer or exchange and where notices and
demands to or upon the Company in respect of the Securities, the Subsidiary
Guarantees and this Indenture may be served. The office of U.S. Bank Trust
National Association located at 100 Wall Street, Suite 1600, New York, NY 10005,
Attn: Corporate Trust Department, shall be such office or agency of the Company,
unless the Company shall designate and maintain some other office or agency for
one or more of such purposes. The Company will give prompt written notice to the
Trustee of any change in the location of any such office or agency. If at any
time the Company shall fail to maintain any such required office or agency or
shall fail to furnish the Trustee with the address thereof, such presentations,
surrenders, notices and demands may be made or served at the aforementioned
office of the Trustee, and the Company hereby appoints the Trustee as its agent
to receive all such presentations, surrenders, notices and demands.

     The Company may also from time to time designate one or more other offices
or agencies (in or outside of The City of New York) where the Securities may be
presented or surrendered for any or all such purposes and may from time to time
rescind any such designation; provided, however, that no such designation or
rescission shall in any manner relieve the Company of its obligation to maintain
an office or agency in the Borough of Manhattan, The City of New York for such
purposes.  The Company will give prompt written notice to the Trustee of any
such designation or rescission and any change in the location of any such other
office or agency.

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     Section 10.3 Money for Security Payments to Be Held in Trust.  If the
Company shall at any time act as its own Paying Agent, it shall, on or before
each due date of the principal of (and premium, if any, on) or interest on any
of the Securities, segregate and hold in trust for the benefit of the Persons
entitled thereto a sum sufficient to pay the principal (and premium, if any) or
interest so becoming due until such sums shall be paid to such Persons or
otherwise disposed of as herein provided and will promptly notify the Trustee of
its action or failure so to act.

     Whenever the Company shall have one or more Paying Agents for the
Securities, it will, on or before 12:00 noon on each due date of the principal
of (and premium, if any, on), or interest on, any Securities, deposit with a
Paying Agent a sum sufficient to pay the principal (and premium, if any) or
interest so becoming due, such sum to be held in trust for the benefit of the
Persons entitled to such principal, premium or interest, and (unless such Paying
Agent is the Trustee) the Company shall promptly notify the Trustee of such
action or any failure so to act.

     The Company shall cause each Paying Agent (other than the Trustee) to
execute and deliver to the Trustee an instrument in which such Paying Agent
shall agree with the Trustee, subject to the provisions of this Section, that
such Paying Agent will:

          (a) hold all sums held by it for the payment of the principal of (and
premium, if any, on) or interest on Securities in trust for the benefit of the
Persons entitled thereto until such sums shall be paid to such Persons or
otherwise disposed of as herein provided;

          (b) give the Trustee notice of any default by the Company (or any
other obligor upon the Securities) in the making of any payment of principal
(and premium, if any) or interest; and

          (c) at any time during the continuance of any such default, upon the
written request of the Trustee, forthwith pay to the Trustee all sums so held in
trust by such Paying Agent.

     The Company may at any time, for the purpose of obtaining the satisfaction
and discharge of this Indenture or for any other purpose, pay, or by Company
Order direct any Paying Agent to pay, to the Trustee all sums held in trust by
the Company or such Paying Agent, such sums to be held by the Trustee upon the
same trusts as those upon which such sums were held by the Company or such
Paying Agent; and, upon such payment by any Paying Agent to the Trustee, such
Paying Agent shall be released from all further liability with respect to such
sums.

     Subject to applicable escheat and abandoned property laws, any money
deposited with the Trustee or any Paying Agent, or then held by the Company, in
trust for the payment of the principal of (and premium, if any, on) or interest
on any Security and remaining unclaimed for two years after such principal (and
premium, if any) or interest has become due and payable shall be paid to the
Company on Company Request, or (if then held by the Company) shall be discharged
from such trust; and the Holder of such Security shall thereafter, as an
unsecured general creditor, look only to the Company for payment thereof, and
all liability of the Trustee or such Paying Agent with respect to such trust
money, and all liability of the Company as trustee thereof, shall thereupon

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<PAGE>
 
cease; provided, however, that the Trustee or such Paying Agent, before being
required to make any such repayment, may at the expense of the Company cause to
be published once, in a newspaper published in the English language, customarily
published on each Business Day and of general circulation in the Borough of
Manhattan, The City of New York, notice that such money remains unclaimed and
that, after a date specified therein, which shall not be less than 30 days from
the date of such publication, any unclaimed balance of such money then remaining
will be repaid to the Company.

     Section 10.4 Corporate Existence.  Except as expressly permitted by Article
VIII hereof, Section 10.16 hereof or other provisions of this Indenture, the
Company shall do or cause to be done all things necessary to preserve and keep
in full force and effect the corporate existence, rights (charter and statutory)
and franchises of the Company and each Restricted Subsidiary; provided, however,
that the Company shall not be required to preserve any such existence of its
Restricted Subsidiaries, rights or franchises, if the Board of Directors shall
determine that the preservation thereof is no longer desirable in the conduct of
the business of the Company and its Restricted Subsidiaries, taken as a whole
and that the loss thereof is not disadvantageous in any material respect to the
Holders.

     Section 10.5 Payment of Taxes and Other Claims.  The Company shall pay or
discharge or cause to be paid or discharged, before the same shall become
delinquent, (a) all taxes, assessments and governmental charges levied or
imposed upon the Company or any Restricted Subsidiary or upon the income,
profits or Property of the Company or any Restricted Subsidiary and (b) all
lawful claims for labor, materials and supplies, which, if unpaid, might by law
become a Lien upon the Property of the Company or any Restricted Subsidiary;
provided, however, that the Company shall not be required to pay or discharge or
cause to be paid or discharged any such tax, assessment, charge or claim whose
amount, applicability or validity is being contested in good faith by
appropriate proceedings and for which appropriate provision has been made in
accordance with GAAP.

     Section 10.6 Maintenance of Properties. The Company shall cause all
material Properties owned by the Company or any Restricted Subsidiary and used
or held for use in the conduct of its business or the business of any Restricted
Subsidiary to be maintained and kept in good condition, repair and working order
(ordinary wear and tear excepted), all as in the judgment of the Company may be
necessary so that its business may be properly and advantageously conducted at
all times; provided, however, that nothing in this Section shall prevent the
Company from discontinuing the maintenance of any of such Properties if such
discontinuance is, in the judgment of the Company, desirable in the conduct of
its business or the business of the Company and its Restricted Subsidiaries
taken as a whole and not disadvantageous in any material respect to the Holders.
Notwithstanding the foregoing, nothing contained in this Section 10.6 shall
limit or impair in any way the right of the Company and its Restricted
Subsidiaries to sell, divest and otherwise to engage in transactions that are
otherwise permitted by this Indenture.

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<PAGE>
 
     Section 10.7 Insurance.  The Company shall at all times keep all of its and
its Restricted Subsidiaries' Properties which are of an insurable nature insured
with insurers, believed by the Company to be responsible, against loss or damage
to the extent that property of similar character is usually so insured by
corporations similarly situated and owning like properties.

     The Company may adopt such other plan or method of protection, in lieu of
or supplemental to insurance with insurers, whether by the establishment of an
insurance fund or reserve to be held and applied to make good losses from
casualties, or otherwise, conforming to the systems of self-insurance maintained
by corporations similarly situated and owning like properties, as may be
determined by the Board of Directors.

     Section 10.8 Statement by Officers as to Default.

          (a) The Company shall deliver to the Trustee, within 90 days after the
end of each fiscal year of the Company and within 45 days of the end of each of
the first, second and third quarters of each fiscal year of the Company, an
Officers' Certificate stating that a review of the activities of the Company and
its Subsidiaries during the preceding fiscal quarter or fiscal year, as
applicable, has been made under the supervision of the signing Officers with a
view to determining whether the Company has kept, observed, performed and
fulfilled its obligations under this Indenture, and further stating, as to each
such Officer signing such certificate, that to the best of such Officer's
knowledge the Company has kept, observed, performed and fulfilled each and every
covenant contained in this Indenture and is not in default in the performance or
observance of any of the terms, provisions and conditions hereof (or, if a
Default or Event of Default shall have occurred and be continuing, describing
all such Defaults or Events of Default of which such Officer may have knowledge
and what action the Company is taking or proposes to take with respect thereto).
Such Officers' Certificate shall comply with TIA Section 314(a)(4). For purposes
of this Section 10.8(a), such compliance shall be determined without regard to
any period of grace or requirement of notice under this Indenture.

          (b) The Company and the Subsidiary Guarantors shall, so long as any of
the Securities are outstanding, deliver to the Trustee forthwith upon any
Officer becoming aware of any Default or Event of Default or default in the
performance of any covenant, agreement or condition contained in this Indenture,
an Officers' Certificate specifying such Default or Event of Default and what
action the Company or any Subsidiary Guarantor proposes to take with respect
thereto within 10 days of its occurrence.

     Section 10.9 Provision of Financial Information.  The Company and the
Subsidiary Guarantors shall file with the Trustee (with exhibits) and deliver to
each Holder (without exhibits), without cost to such Holder, within 15 days
after it files them with the Commission (or would have been required to file
them with the Commission if such filing were required), copies of the annual and
quarterly reports and of the information, documents and other reports (or copies
of such portions of any of the foregoing as the Commission may by rules and
regulations prescribe) which each of the Company and the Subsidiary Guarantors
is required to file with the Commission pursuant to 

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<PAGE>
 
Section 13 or 15(d) of the Exchange Act. If the Company is not subject to the
requirements of Section 13 or 15(d) of the Exchange Act, the Company shall
nonetheless file with the Commission (to the extent such filings are accepted by
the Commission) and the Trustee, and deliver to each Holder (without exhibits),
without cost to such Holder, copies of such annual reports and such information,
documents and other reports as it would file if it were subject to the
requirements of Section 13 or 15(d) of the Exchange Act. If filing such reports
and documents with the Commission is not accepted by the Commission or is
prohibited under the Exchange Act, the Company shall supply at the Company's
cost copies of such reports and documents to any Holder of Securities promptly
upon written request. The Company is obligated to make available, upon request,
to any Holder of Securities the information required by Rule 144A(d)(4) under
the Securities Act, during any period in which the Company is not subject to
Section 13 or 15(d) of the Exchange Act. So long as any Transfer Restricted
Securities remain outstanding during any period in which the Company is not
subject to Section 13 or 15(d) of the Exchange Act, the Company shall furnish to
all Holders and prospective purchasers of the Securities designated by the
Holders of Transfer Restricted Securities, promptly upon their request, the
information required to be delivered pursuant to Rule 144A(d)(4) of the
Securities Act. The Company and each Subsidiary Guarantor also shall comply with
the other provisions of TIA Section 314(a).

     Section 10.10 Limitation on Other Senior Subordinated Indebtedness.  The
Company will not incur, directly or indirectly, any Indebtedness which is
expressly subordinate or junior in right of payment in any respect to Senior
Indebtedness unless such Indebtedness (i) ranks pari passu in right of payment
with the Securities pursuant to subordination provisions substantially similar
to those contained in Article XIV hereof, or (ii) is expressly subordinated in
right of payment to the Securities.

     Section 10.11 Limitation on Restricted Payments.

          (a) The Company shall not, and shall not permit any Restricted
Subsidiary to, directly or indirectly, take the following actions:

              (i) declare or pay any dividend on, or make any distribution to
     holders of, any shares of the Company's Capital Stock (other than dividends
     or distributions payable solely in shares of Qualified Capital Stock of the
     Company or in options, warrants or other rights to purchase Qualified
     Capital Stock of the Company);

              (ii) purchase, redeem or otherwise acquire or retire for value any
     Capital Stock of the Company or any Affiliate thereof (other than any
     Wholly Owned Restricted Subsidiary of the Company) or any options, warrants
     or other rights to acquire such Capital Stock (other than with respect to
     any such Capital Stock or other interests held by the Company or any Wholly
     Owned Restricted Subsidiary of the Company);

              (iii) make any principal payment on or repurchase, redeem, defease
     or otherwise acquire or retire for value, prior to any scheduled principal
     payment, scheduled sinking fund 

                                       88
<PAGE>
 
     payment or maturity, any Subordinated Indebtedness, except in any case out
     of a Net Proceeds Deficiency pursuant to the terms of this Indenture and
     except upon the occurrence of a Change of Control to the extent (and only
     to the extent) required by the indenture or other agreement or instrument
     pursuant to which such Subordinated Indebtedness was issued, provided that
     the Company is then in compliance with its obligations under Section 10.16
     hereof;

              (iv) declare or pay any dividend on, or make any distribution to
     the holders of, any shares of Capital Stock of any Restricted Subsidiary of
     the Company (other than to the Company or any of its Wholly Owned
     Restricted Subsidiaries) or purchase, redeem or otherwise acquire or retire
     for value any Capital Stock of any Restricted Subsidiary or any options,
     warrants or other rights to acquire any such Capital Stock (other than with
     respect to any such Capital Stock or other interests held by the Company or
     any Wholly Owned Restricted Subsidiary of the Company); or

              (v) make any Investment (other than any Permitted Investment);

(such payments or other actions described in (but not excluded from) clauses (i)
through (v) are collectively referred to as "Restricted Payments") , unless at
the time of and after giving effect to the proposed Restricted Payment (the
amount of any such Restricted Payment, if other than cash, shall be the amount
determined by the Board of Directors of the Company, whose determination shall
be conclusive and evidenced by a Board Resolution), (A) no Default or Event of
Default shall have occurred and be continuing, (B) the Company could incur $1.00
of additional Indebtedness (excluding Permitted Indebtedness) in accordance with
Section 10.12 hereof, and (C) the aggregate amount of all Restricted Payments
declared or made after the Issue Date shall not exceed the sum (without
duplication) of the following:

              (1) 50% of the aggregate cumulative Consolidated Net Income of the
     Company (including, without limitation, notwithstanding clause (d) of the
     definition of "Consolidated Net Income," the Consolidated Net Income of
     each of Ocean Energy, Inc. and United Meridian Corporation prior to their
     merger) accrued on a cumulative basis during the period beginning June 1,
     1997 and ending on the last day of the Company's last fiscal quarter ending
     prior to the date of such proposed Restricted Payment (or, if such
     aggregate cumulative Consolidated Net Income shall be a loss, minus 100% of
     such loss), plus

              (2) the aggregate net cash proceeds received after June 1, 1997 by
     the Company as capital contributions to the Company (other than from any
     Restricted Subsidiary), plus

              (3) the aggregate net cash proceeds received after June 1, 1997,
     by the Company from the issuance or sale (other than to any of its
     Restricted Subsidiaries) of shares of Qualified Capital Stock of the
     Company or any options, warrants or rights to purchase such shares of
     Qualified Capital Stock of the Company, plus

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<PAGE>
 
              (4) the aggregate net cash proceeds received after June 1, 1997 by
     the Company (other than from any of its Restricted Subsidiaries) upon the
     exercise of any options, warrants or rights to purchase shares of Qualified
     Capital Stock of the Company, plus

              (5) the aggregate net cash proceeds received after June 1, 1997 by
     the Company from the issuance or sale (other than to any of its Restricted
     Subsidiaries) of debt securities or shares of Redeemable Capital Stock that
     have been converted into or exchanged for Qualified Capital Stock of the
     Company to the extent such debt securities were originally sold for cash,
     together with the aggregate cash received by the Company at the time of
     such conversion or exchange, plus

              (6) the aggregate net cash proceeds received after June 1, 1997 by
     the Company or its Restricted Subsidiaries, computed on a consolidated
     basis, constituting a return of capital on an Investment (other than a
     Permitted Investment) made by the Company or any Restricted Subsidiary
     after June 1, 1997, including, without limitation, from the redesignation
     of an Unrestricted Subsidiary as a Restricted Subsidiary (valued in each
     case as provided in the definition of Investment), not to exceed in the
     case of any Unrestricted Subsidiary the total amount of Investments (other
     than Permitted Investments) in such Unrestricted Subsidiary made by the
     Company and its Restricted Subsidiaries in such Unrestricted Subsidiary
     after June 1, 1997, plus

              (7) $50,000,000.

          (b) Notwithstanding paragraph (a) above, the Company and its
Restricted Subsidiaries may take the following actions so long as (in the case
of clauses (ii), (iii) and (iv) below) no Default or Event of Default shall have
occurred and be continuing:

              (i) the payment of any dividend within 60 days after the date of
     declaration thereof, if at such declaration date such declaration complied
     with the provisions of paragraph (a) above (and such payment shall be
     deemed to have been paid on such date of declaration for purposes of any
     calculation required by the provisions of paragraph (a) above);

              (ii) the repurchase, redemption or other acquisition or retirement
     of any shares of any class of Capital Stock of the Company or any
     Restricted Subsidiary, in exchange for, or out of the aggregate net cash
     proceeds of, a substantially concurrent issue and sale (other than to a
     Restricted Subsidiary) of shares of Qualified Capital Stock of the Company;

              (iii) the purchase, redemption, repayment, defeasance or other
     acquisition or retirement for value of any Subordinated Indebtedness (other
     than Redeemable Capital Stock) in exchange for or out of the aggregate net
     cash proceeds of a substantially concurrent issue and sale (other than to a
     Restricted Subsidiary) of shares of Qualified Capital Stock of the Company;
     and

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<PAGE>
 
              (iv) the purchase, redemption, repayment, defeasance or other
     acquisition or retirement for value of Subordinated Indebtedness (other
     than Redeemable Capital Stock) in exchange for, or out of the aggregate net
     cash proceeds of a substantially concurrent incurrence (other than to a
     Restricted Subsidiary) of, Subordinated Indebtedness of the Company so long
     as (A) the principal amount of such new Indebtedness does not exceed the
     principal amount (or, if such Subordinated Indebtedness being refinanced
     provides for an amount less than the principal amount thereof to be due and
     payable upon a declaration of acceleration thereof, such lesser amount as
     of the date of determination) of the Subordinated Indebtedness being so
     purchased, redeemed, repaid, defeased, acquired or retired, plus the amount
     of any premium required to be paid in connection with such refinancing
     pursuant to the terms of the Subordinated Indebtedness refinanced or the
     amount of any premium reasonably determined by the Company as necessary to
     accomplish such refinancing, plus the amount of expenses of the Company
     incurred in connection with such refinancing, (B) such new Subordinated
     Indebtedness is subordinated to the Securities at least to the same extent
     as such Subordinated Indebtedness so purchased, redeemed, repaid, defeased,
     acquired or retired, and (C) such new Subordinated Indebtedness has an
     Average Life to Stated Maturity that is longer than the Average Life to
     Stated Maturity of the Securities and such new Subordinated Indebtedness
     has a Stated Maturity for its final scheduled principal payment that is at
     least 91 days later than the Stated Maturity for the final scheduled
     principal payment of the Securities.

The actions described in clauses (i), (ii) and (iii) of this paragraph (b) shall
be Restricted Payments that shall be permitted to be taken in accordance with
this paragraph (b) but shall reduce the amount that would otherwise be available
for Restricted Payments under clause (C) of paragraph (a) (provided that any
dividend paid pursuant to clause (i) of this paragraph (b) shall reduce the
amount that would otherwise be available under clause (C) of paragraph (a) when
declared, but not also when subsequently paid pursuant to such clause (i)), and
the actions described in clause (iv) of this paragraph (b) shall be Restricted
Payments that shall be permitted to be taken in accordance with this paragraph
and shall not reduce the amount that would otherwise be available for Restricted
Payments under clause (C) of paragraph (a).

          (c) In computing Consolidated Net Income of the Company under
paragraph (a) above, (1) the Company shall use audited financial statements for
the portions of the relevant period for which audited financial statements are
available on the date of determination and unaudited financial statements and
other current financial data based on the books and records of the Company for
the remaining portion of such period and (2) the Company shall be permitted to
rely in good faith on the financial statements and other financial data derived
from the books and records of the Company that are available on the date of
determination. If the Company makes a Restricted Payment which, at the time of
the making of such Restricted Payment would in the good faith determination of
the Company be permitted under the requirements of this Indenture, such
Restricted Payment shall be deemed to have been made in compliance with this
Indenture notwithstanding any subsequent adjustments made in good faith to the
Company's financial statements affecting Consolidated Net Income of the Company
for any period.

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<PAGE>
 
     Section 10.12 Limitation on Indebtedness.  The Company shall not, and
shall not permit any Restricted Subsidiary to create, incur, issue, assume,
guarantee or in any manner become directly or indirectly liable for the payment
of (collectively "incur") any Indebtedness (including any Acquired
Indebtedness), other than Permitted Indebtedness and Permitted Subsidiary
Indebtedness, as the case may be; provided, however, that the Company and its
Restricted Subsidiaries that are either Subsidiary Guarantors or Foreign
Subsidiaries may incur Indebtedness (and Restricted Subsidiaries that are not
Subsidiary Guarantors or  Foreign Subsidiaries may incur Acquired Indebtedness)
if (x) the Company's Consolidated Fixed Charge Coverage Ratio for the four full
fiscal quarters immediately preceding the incurrence of such Indebtedness (and
for which financial statements are available), taken as one period (at the time
of such incurrence, after giving pro forma effect to:  (i) the incurrence of
such Indebtedness and (if applicable) the application of the net proceeds
therefrom, including to refinance other Indebtedness, as if such Indebtedness
was incurred and the application of such proceeds occurred at the beginning of
such four-quarter period; (ii) the incurrence, repayment or retirement of any
other Indebtedness (including Permitted Indebtedness) by the Company or its
Restricted Subsidiaries since the first day of such four-quarter period
(including any other Indebtedness to be incurred concurrent with the incurrence
of such Indebtedness) as if such Indebtedness was incurred, repaid or retired at
the beginning of such four-quarter period; and (iii) notwithstanding clause (d)
of the definition of Consolidated Net Income, the acquisition (whether by
purchase, merger or otherwise) or disposition (whether by sale, merger or
otherwise) of any Person (or any properties outside of the ordinary course of
business) acquired or disposed of by the Company or its Restricted Subsidiaries,
as the case may be, since the first day of such four-quarter period, as if such
acquisition or disposition occurred at the beginning of such four-quarter
period), would have been equal to at least 2.5 to 1.0.  The incurrence of
certain guarantees by certain Restricted Subsidiaries is further limited by
Section 10.13 hereof.

     Section 10.13 Limitation on Guarantees of Indebtedness by Subsidiaries;
Additional Subsidiary Guarantors.

          (a) The Company shall not permit any Restricted Subsidiary that is not
a Subsidiary Guarantor to guarantee the payment of any Indebtedness of the
Company unless (i) (A) such Restricted Subsidiary simultaneously executes and
delivers a supplemental indenture to this Indenture providing for a Subsidiary
Guarantee of the Securities by such Restricted Subsidiary which Subsidiary
Guarantee will be subordinated to Guarantor Senior Indebtedness (but no other
Indebtedness) to the same extent that the Securities are subordinated to Senior
Indebtedness and (B) with respect to any guarantee of Subordinated Indebtedness
by a Restricted Subsidiary, any such guarantee shall be subordinated to such
Restricted Subsidiary's Subsidiary Guarantee at least to the same extent as such
Subordinated Indebtedness is subordinated to the Securities; (ii) except to the
extent contemplated by Section 13.5 hereof, such Restricted Subsidiary waives
and will not in any manner whatsoever claim or take the benefit or advantage of,
any rights of reimbursement, indemnity or subrogation or any other rights
against the Company or any other Restricted Subsidiary as a result of any
payment by such Restricted Subsidiary under its Subsidiary Guarantee until such
time as the obligations guaranteed thereby are paid in full; and (iii) such
Restricted Subsidiary shall deliver to the Trustee an Opinion of Counsel to the
effect that such Subsidiary Guarantee has been 

                                       92
<PAGE>
 
duly executed and authorized and constitutes a valid, binding and enforceable
obligation of such Restricted Subsidiary, except insofar as enforcement thereof
may be limited by bankruptcy, insolvency or similar laws (including, without
limitation, all laws relating to fraudulent transfers) and except insofar as
enforcement thereof is subject to general principles of equity; provided that
this paragraph (a) shall not be applicable to any guarantee of any Restricted
Subsidiary that (x) existed at the time such Person became a Restricted
Subsidiary of the Company and (y) was not incurred in connection with, or in
contemplation of, such Person becoming a Restricted Subsidiary of the Company.

          (b) The Company may from time to time, at its option, nominate any
Restricted Subsidiary as an additional Subsidiary Guarantor.  Any such
Restricted Subsidiary shall execute and deliver a supplemental indenture to this
Indenture agreeing to guarantee the Securities.  At the election of the Company,
such Subsidiary Guarantee may contain such release provisions as the Company may
deem appropriate (including, without limitation, release provisions of the type
in paragraph (c) below).

          (c) Notwithstanding the foregoing paragraph (a) and the other
provisions of this Indenture, any Subsidiary Guarantee incurred by a Restricted
Subsidiary pursuant to this Section 10.13 may, at the election of the Company,
provide by its terms that it shall be automatically and unconditionally released
and discharged upon (i) any sale, exchange or transfer, to any Person that is
not an Affiliate of the Company, of all of the Company's Capital Stock in, or
all or substantially all the Property of, such Restricted Subsidiary (which
sale, exchange or transfer is not prohibited by this Indenture), (ii) the merger
of such Restricted Subsidiary into the Company or any other Restricted
Subsidiary (provided the surviving Restricted Subsidiary assumes the Subsidiary
Guarantee) or the liquidation and dissolution of such Restricted Subsidiary (in
each case to the extent not prohibited by this Indenture), or (iii) the release
or discharge of the guarantee which resulted in the creation of such Subsidiary
Guarantee, except a discharge or release by or as a result of payment under such
guarantee.

          (d) Unless specified to the contrary in a supplemental indenture
hereto, any Subsidiary Guarantee incurred by a Restricted Subsidiary pursuant to
this Section 10.13 shall be deemed to provide for the release and discharge
thereof as contemplated by Sections 10.13(c) and 13.3 hereof.

     Section 10.14 Limitation on Issuances and Sale of Capital Stock by
Restricted Subsidiaries. The Company (a) shall not permit any Restricted
Subsidiary to issue any Capital Stock (other than to the Company or a Wholly
Owned Restricted Subsidiary) and (b) shall not permit any Person (other than the
Company or a Wholly Owned Restricted Subsidiary) to own any Capital Stock of any
Restricted Subsidiary, except, in each case, for (i) directors' qualifying
shares, (ii) Capital Stock of a Restricted Subsidiary organized in a foreign
jurisdiction required to be issued to, or owned by, the government of such
foreign jurisdiction or individual or corporate citizens of such foreign
jurisdiction in order for such Restricted Subsidiary to transact business in
such foreign jurisdiction, (iii) a sale of all or substantially all the Capital
Stock of a Restricted Subsidiary effected in

                                       93
<PAGE>
 
accordance with Section 10.17 hereof, (iv) the Capital Stock of a Restricted
Subsidiary owned by a Person at the time such Restricted Subsidiary became a
Restricted Subsidiary or acquired by such Person in connection with the
formation of the Restricted Subsidiary and (v) Capital Stock of Havre Pipeline
Company, LLC and Capital Stock of Big Sky Gas Marketing L.L.C.; provided,
however, that any Capital Stock retained by the Company or a Restricted
Subsidiary shall be treated as an Investment for purposes of Section 10.11
hereof if the amount of such Capital Stock represents less than a majority of
the Voting Stock of such Restricted Subsidiary.

     Section 10.15 Limitation on Liens. The Company shall not, and shall not
permit any Restricted Subsidiary to, directly or indirectly, create, incur,
assume, affirm or suffer to exist or become effective any Lien of any kind
except for Permitted Liens, on or with respect to any of its Property or assets
(including any intercompany notes), whether owned at the Issue Date or
thereafter acquired, or any income, profits or proceeds therefrom, or assign or
otherwise convey any right to receive income thereon, unless (x) in the case of
any Lien securing Subordinated Indebtedness, the Securities are secured by a
Lien on such Property, assets or proceeds that is senior in priority to such
Lien and (y) in the case of any other Lien, the Securities are directly secured
equally and ratably with the obligation or liability secured by such Lien.

     Section 10.16 Purchase of Securities Upon Change of Control.

          (a) Upon the occurrence of a Change of Control, the Company shall be
obligated to make an offer to purchase all of the then outstanding Securities (a
"Change of Control Offer"), and shall purchase, on a business day (the "Change
of Control Purchase Date") not more than 70 nor less than 30 days following the
Change of Control, all of the then outstanding Securities validly tendered
pursuant to such Change of Control Offer, at a purchase price (the "Change of
Control Purchase Price") equal to 101% of the principal amount thereof plus
accrued and unpaid interest, if any, to the Change of Control Purchase Date.

          (b) The Change of Control Offer is required to remain open for at
least 20 Business Days and until the close of business on the Change of Control
Purchase Date. The Company will not be required to make a Change of Control
Offer upon a Change of Control if a third party makes the Change of Control
Offer at the same purchase price, at the same times and otherwise in substantial
compliance with the requirements applicable to a Change of Control Offer made by
the Company and purchases all Securities validly tendered and not withdrawn
under such Change of Control Offer.

          (c) Not later than the 30th day following any Change of Control, the
Company shall give to the Trustee in the manner provided in Section 15.4 and
each Holder of the Securities in the manner provided in Section 15.5, a notice
(the "Change of Control Notice") stating:

              (1) that a Change of Control has occurred and that such Holder has
     the right to require the Company to repurchase such Holder's Securities, or
     portion thereof, at the Change of Control Purchase Price;

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<PAGE>
 
              (2) any information regarding such Change of Control required to
     be furnished pursuant to Rule 14e-1 under the Exchange Act and any other
     securities laws and regulations thereunder;

              (3) the Change of Control Purchase Date which shall be on a
     Business Day and no earlier than 30 days nor later than 70 days from the
     date the Change of Control occurred;

              (4) that any Security, or portion thereof, not tendered or
     accepted for payment will continue to accrue interest;

              (5) that unless the Company defaults in depositing money with the
     Paying Agent in accordance with the last paragraph of clause (d) of this
     Section 10.16, or payment is otherwise prevented, any Security, or portion
     thereof, accepted for payment pursuant to the Change of Control Offer shall
     cease to accrue interest after the Change of Control Purchase Date; and

              (6) the instructions a Holder must follow in order to have its
     Securities repurchased in accordance with paragraph (d) of this Section.

          (d) Holders electing to have Securities purchased will be required to
surrender such Securities to the Company at the address specified in the Change
of Control Notice at least five Business Days prior to the Change of Control
Purchase Date.  Holders will be entitled to withdraw their election if the
Company receives, not later than three Business Days prior to the Change of
Control Purchase Date, a telegram, telex, facsimile transmission or letter
setting forth the name of the Holder, the certificate number(s) and principal
amount of the Securities delivered for purchase by the Holder as to which his
election is to be withdrawn and a statement that such Holder is withdrawing his
election to have such Securities purchased.  Holders whose Securities are
purchased only in part will be issued new Securities equal in principal amount
to the unpurchased portion of the Securities surrendered.

          On the Change of Control Purchase Date, the Company shall (i) accept
for payment Securities or portions thereof tendered pursuant to a Change of
Control Offer, (ii) deposit with the Paying Agent money sufficient to pay the
purchase price of all Securities or portions thereof so tendered, and (iii)
deliver or cause to be delivered to the Trustee the Securities so accepted.  The
Paying Agent shall promptly mail or deliver to Holders of the Securities so
tendered payment in an amount equal to the purchase price for the Securities,
and the Company will promptly execute and the Trustee will promptly authenticate
and mail or make available for delivery to such Holders a new Security equal in
principal amount to any unpurchased portion of the Security which any such
Holder did not surrender for purchase.  The Company shall announce the results
of a Change of Control Offer on or as soon as practicable after the Change of
Control Purchase Date.  For purposes of this Section 10.16, the Trustee will act
as the Paying Agent.

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<PAGE>
 
          (e) The Company shall comply with Rule 14e-1 under the Exchange Act
and any other securities laws and regulations thereunder to the extent such laws
and regulations are applicable, in the event that a Change of Control occurs and
the Company is required to purchase Securities as described above.

     Section 10.17 Disposition of Proceeds of Asset Sales.

          (a) The Company will not, and will not permit any Restricted
Subsidiary to, engage in any Asset Sale unless (i) the Company or such
Restricted Subsidiary, as the case may be, receives consideration at the time of
such Asset Sale at least equal to the Fair Market Value of the assets and
Properties sold or otherwise disposed of pursuant to the Asset Sale (as
determined by the Board of Directors of the Company, whose determination shall
be conclusive and evidenced by a Board Resolution) and (ii) at least 70% of the
consideration received by the Company or the Restricted Subsidiary, as the case
may be, in respect of such Asset Sale consists of cash, Cash Equivalents or the
assumption by the purchaser of liabilities of the Company (other than
liabilities of the Company that are by their terms subordinated to the
Securities) or any Restricted Subsidiary as a result of which the Company and
its remaining Restricted Subsidiaries are no longer liable.

          (b) If the Company or any Restricted Subsidiary engages in an Asset
Sale the Company may either (x) apply the Net Cash Proceeds thereof to
permanently reduce Senior Indebtedness or to permanently reduce Guarantor Senior
Indebtedness, or (y) invest all or any part of the Net Cash Proceeds thereof,
within 365 days after such Asset Sale, in Properties and assets which replace
the Properties and assets that were the subject of the Asset Sale or in
Properties and assets that will be used in the business of the Company or its
Restricted Subsidiaries, as the case may be ("Replacement Assets"). The amount
of such Net Cash Proceeds not applied or invested as provided in this paragraph
constitutes "Excess Proceeds."

          (c) When the aggregate amount of Excess Proceeds equals or exceeds
$20,000,000 (the "Trigger Date"), the Company shall make an offer to purchase,
from all Holders of the Securities and holders of any then outstanding Pari
Passu Indebtedness required to be repurchased or repaid on a permanent basis in
connection with an Asset Sale, an aggregate principal amount of Securities and
any such Pari Passu Indebtedness equal to such Excess Proceeds as follows:

              (i) (A) not later than the 30th day following the Trigger Date,
     the Company shall give to the Trustee in the manner provided in Section
     15.4 hereof and each Holder of the Securities in the manner provided in
     Section 15.5 hereof, a notice (a "Purchase Notice") offering to purchase (a
     "Net Proceeds Offer") from all Holders of the Securities in accordance with
     the procedures set forth herein the maximum principal amount (expressed as
     a multiple of $1,000) of Securities that may be purchased out of an amount
     (the "Payment Amount") equal to the product of such Excess Proceeds
     multiplied by a fraction, the numerator of which is the outstanding
     principal amount of the Securities and the denominator of which is the sum
     of the outstanding principal amount of the Securities and

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<PAGE>
 
     such Pari Passu Indebtedness, if any (subject to proration in the event
     such amount is less than the aggregate Offered Price (as hereinafter
     defined) of all Securities tendered), and (B) to the extent required by
     such Pari Passu Indebtedness and provided there is a permanent reduction in
     the principal amount of such Pari Passu Indebtedness, the Company shall
     make an offer to purchase Pari Passu Indebtedness (a "Pari Passu Offer") in
     an amount (the "Pari Passu Indebtedness Amount") equal to the excess of the
     Excess Proceeds over the Payment Amount.

              (ii) The offer price for the Securities shall be payable in cash
     in an amount equal to 100% of the principal amount of the Securities
     tendered pursuant to a Net Proceeds Offer, plus accrued and unpaid
     interest, if any, to the date such Net Proceeds Offer is consummated (the
     "Offered Price"), in accordance with the procedures set forth herein. To
     the extent that the aggregate Offered Price of the Securities tendered
     pursuant to a Net Proceeds Offer is less than the Payment Amount relating
     thereto or the aggregate amount of the Pari Passu Indebtedness that is
     purchased or repaid pursuant to the Pari Passu Offer is less than the Pari
     Passu Indebtedness Amount (such shortfall constituting a "Net Proceeds
     Deficiency"), the Company may use such Net Proceeds Deficiency, or a
     portion thereof, for general corporate purposes, subject to the limitations
     of Section 10.11 hereof.

              (iii) If the aggregate Offered Price of Securities validly
     tendered and not withdrawn by Holders thereof exceeds the Payment Amount,
     Securities to be purchased will be selected on a pro rata basis by the
     Trustee based on the principal amount of Securities so tendered. Upon
     completion of such Net Proceeds Offer and Pari Passu Offer, the amount of
     Excess Proceeds shall be reset to zero.

              (iv) The Purchase Notice shall set forth a purchase date (the "Net
     Proceeds Payment Date"), which shall be on a Business Day no earlier than
     30 days nor later than 70 days from the Trigger Date.  The Purchase Notice
     shall also state (i) that a Trigger Date with respect to one or more Asset
     Sales has occurred and that such Holder has the right to require the
     Company to repurchase such Holders, Securities at the Offered Price,
     subject to the limitations described in this Section, (ii) any information
     regarding such Net Proceeds Offer required to be furnished pursuant to Rule
     14e-1 under the Exchange Act and any other securities laws and regulations
     thereunder, (iii) that any Security, or portion thereof, not tendered or
     accepted for payment will continue to accrue interest, (iv) that, unless
     the Company defaults in depositing money with the Paying Agent in
     accordance with the last paragraph of clause (d) of this Section 10.17, or
     payment is otherwise prevented, any Security, or portion thereof, accepted
     for payment pursuant to the Net Proceeds Offer shall cease to accrue
     interest after the Net Proceeds Payment Date, and (v) the instructions a
     Holder must follow in order to have its Securities repurchased in
     accordance with paragraph (d) of this Section.

          (d) Holders electing to have Securities purchased will be required to
surrender such Securities to the Company at the address specified in the
Purchase Notice at least five Business

                                       97
<PAGE>
 
Days prior to the Net Proceeds Payment Date.  Holders will be entitled to
withdraw their election if the Company receives, not later than three Business
Days prior to the Net Proceeds Payment Date, a telegram, telex, facsimile
transmission or letter setting forth the name of the Holder, the certificate
number(s) and principal amount of the Securities delivered for purchase by the
Holder as to which his election is to be withdrawn and a statement that such
Holder is withdrawing his election to have such Securities purchased.  Holders
whose Securities are purchased only in part will be issued new Securities equal
in principal amount to the unpurchased portion of the Securities surrendered.

          On the Net Proceeds Payment Date, the Company shall (i) accept for
payment Securities or portions thereof tendered pursuant to a Net Proceeds Offer
in an aggregate principal amount equal to the Payment Amount or such lesser
amount of Securities as has been tendered, (ii) deposit with the Paying Agent
money sufficient to pay the purchase price of all Securities or portions thereof
so tendered in an aggregate principal amount equal to the Payment Amount or such
lesser amount and (iii) deliver or cause to be delivered to the Trustee the
Securities so accepted.  The Paying Agent shall promptly mail or deliver to
Holders of the Securities so accepted payment in an amount equal to the purchase
price, and the Company shall execute and the Trustee will promptly authenticate
and mail or make available for delivery to such Holders a new Security equal in
principal amount to any unpurchased portion of the Security which any such
Holder did not surrender for purchase.  Any Securities not so accepted will be
promptly mailed or delivered to the Holder thereof.  The Company shall announce
the results of a Net Proceeds Offer on or as soon as practicable after the Net
Proceeds Payment Date.  For purposes of this Section 10.17, the Trustee will act
as the Paying Agent.

     The Company shall not permit any Subsidiary (except a Foreign Subsidiary)
to enter into or suffer to exist any agreement that would place any restriction
of any kind (other than pursuant to law or regulation) on the ability of the
Company to make a Net Proceeds Offer following any Asset Sale. The Company
intends to comply with Rule l4e-1 under the Exchange Act, and any other
securities laws and regulations thereunder, if applicable, in the event that an
Asset Sale occurs and the Company is required to purchase Securities as
described above.

     Section 10.18 Limitation on Transactions with Affiliates. The Company shall
not, and shall not permit any Restricted Subsidiary to, directly or indirectly,
enter into or suffer to exist any transaction or series of related transactions
(including, without limitation, the sale, purchase, exchange or lease of assets,
Property or the rendering of any services) with, or for the benefit of, any
Affiliate of the Company, unless (i) such transaction or series of transactions
are on terms that are no less favorable to the Company or such Restricted
Subsidiary, as the case may be, than those that would be available in a
comparable arm's length transaction with unrelated third parties who are not
Affiliates, (ii) with respect to any one transaction or series of transactions
involving aggregate payments in excess of $10,000,000, the Company delivers an
Officers' Certificate to the Trustee certifying that such transaction or series
of transactions complies with clause (i) above and such transaction or series of
transactions have been approved by a Board Resolution of the Board of Directors
of the Company, and (iii) with respect to any one transaction or series of
transactions involving aggregate payments in excess of $20,000,000, the
Officers' Certificate referred to in

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<PAGE>
 
clause (ii) above also certifies that such transaction or series of transactions
have been approved by a majority of the Disinterested Directors (or, in the
event there are no such Disinterested Directors, that the Company has obtained a
written opinion from an independent nationally recognized investment banking
firm or appraisal firm, in either case specializing or having a specialty in the
type and subject matter of the transaction or series of transactions at issue,
which opinion shall be to the effect set forth in clause (i) above or shall
state that such transaction or series of transactions are fair from a financial
point of view to the Company or such Restricted Subsidiary); provided, however,
that this Section 10.18 shall not apply to (1) the payment of reasonable and
customary regular compensation and fees to directors of the Company who are not
employees of the Company or any Restricted Subsidiary, (2) the payment of
dividends on, or making distributions with respect to, shares of Capital Stock
of the Company on a pro rata basis to the extent permitted by Section 10.11
hereof, (3) transactions between or among the Company and/or any of its Wholly
Owned Restricted Subsidiaries, (4) Restricted Payments permitted by the
provisions of Section 10.11 hereof, (5) loans or advances to officers, directors
and employees of the Company or any Restricted Subsidiary made in the ordinary
course of business and consistent with past practices of the Company and its
Restricted Subsidiaries in an aggregate amount not to exceed $1,000,000
outstanding at any one time, (6) any transaction or series of related
transactions entered into prior to the Issue Date or (7) the Company's employee
compensation and other benefit arrangements.

     Section 10.19 Limitation on Dividend and Other Payment Restrictions
Affecting Restricted Subsidiaries. The Company shall not, and shall not permit
any Restricted Subsidiary to, directly or indirectly, create or otherwise cause
or suffer to exist or become effective any consensual encumbrance or restriction
of any kind on the ability of any Restricted Subsidiary (except a Foreign
Subsidiary) to (a) pay dividends, in cash or otherwise, or make any other
distributions on or in respect of its Capital Stock to the Company or any other
Restricted Subsidiary, (b) pay any Indebtedness owed to the Company or any other
Restricted Subsidiary, (c) make an Investment in the Company or any other
Restricted Subsidiary or (d) transfer any of its Properties or assets to the
Company or any other Restricted Subsidiary, except for such encumbrances or
restrictions (i) pursuant to this Indenture, the Existing Indentures, the Credit
Agreement or any agreement in effect or entered into on the Issue Date, (ii) any
agreement or other instrument of a Person acquired by the Company or any
Restricted Subsidiary in existence at the time of such acquisition (but not
created in contemplation thereof), which encumbrance or restriction is not
applicable to any other Person, or the Properties or assets of any other Person,
other than the Person, or the Property or assets of the Person, so acquired,
(iii) that constitute customary restrictions in leases and licenses relating to
the Property covered thereby and entered into in the ordinary course of
business, (iv) contained in agreements governing Indebtedness permitted to be
incurred in accordance with this Indenture provided that the restrictions are
not materially more restrictive in the aggregate than the restrictions contained
in this Indenture, or (v) existing under any agreement that extends, renews,
refinances or replaces (in whole or in part, and whether or not such prior
agreements remain outstanding) the agreements containing the restrictions in the
foregoing clauses (i), (ii), (iii) and (iv) provided that the terms and
conditions of any such restrictions are not materially less favorable to the
Holders of the Securities than those under or pursuant to the agreement
evidencing the Indebtedness so extended, renewed, refinanced or replaced.

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<PAGE>
 
     Section 10.20 Limitation on Restrictive Covenants. Notwithstanding any
other provision of this Indenture, the restrictive covenants set forth in this
Indenture, including, without limitation, those set forth in Sections 8.1, 10.11
and 10.18, shall be and shall be deemed limited to the extent necessary so that
the creation, existence and effectiveness of such restrictive covenants shall
not result in a breach of the covenant of any of the Existing Indentures
entitled "Limitation on Dividends and Other Payment Restrictions Affecting
Restricted Subsidiaries."

     Section 10.21 Waiver of Certain Covenants. Subject to Section 5.2 hereof,
the Company may omit in any particular instance to comply with any term,
provision or condition set forth in Sections 10.04 through 10.12 and Sections
10.14, 10.15, 10.18 and 10.19 hereof if, before or after the time for such
compliance, the Holders of at least a majority in principal amount of the
Outstanding Securities and the Subsidiary Guarantors, by Act of such Holders and
written agreement of the Subsidiary Guarantors, waive such compliance in such
instance with such term, provision or condition, but no such waiver shall extend
to or affect such term, provision or condition except to the extent so expressly
waived, and, until such waiver shall become effective, the obligations of the
Company and the duties of the Trustee in respect of any such term, provision or
condition shall remain in full force and effect.

     Section 10.22 Suspension of Certain Covenants. The covenants set forth in
this Indenture will be applicable to the Company, except that during any period 
of time that (i) the ratings assigned to the Securities by both S&P and
Moody's (collectively, the "Rating Agencies") are equal to or higher than BBB-
and Baa3, or the equivalents thereof, respectively (the "Investment Grade
Ratings"), except subsequent to a Change of Control of the Company, and (ii) no
Default or Event of Default shall have occurred and be continuing, the Company
and its Subsidiaries shall not be subject to the provisions of Sections 10.10,
10.11, 10.12, 10.14, 10.17, 10.18 and 10.19 hereof and clauses (iii) and (iv) of
Section 8.1 hereof (collectively, the "Suspended Covenants"). In the event that
the Company is not subject to the Suspended Covenants for any period of time as
a result of the preceding sentence (a "Suspension Period") and, subsequently,
one or both Rating Agencies withdraws its ratings or downgrades the ratings
assigned to the Securities below the required Investment Grade Ratings, then,
from and after the date of such withdrawal or downgrade, the Company and its
Subsidiaries will again be subject to the Suspended Covenants and compliance
with the Suspended Covenants with respect to Restricted Payments made after the
time of such withdrawal or downgrade will be calculated in accordance with the
terms of Section 10.11 hereof as if such covenant had been in effect during the
entire period of time from the Issue Date. Notwithstanding any other provision
of this Indenture, the continued existence, after the date of such withdrawal or
downgrade, of facts and circumstances that were incurred or otherwise, came into
being during a Suspension Period shall not constitute a breach of any covenant
set forth in this Indenture or a Default or Event of Default hereunder.

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                                  ARTICLE XI

                           REDEMPTION OF SECURITIES
                           -------------------------

     Section 11.1 Right of Redemption.  Prior to July 1, 2003 (the "Five-Year
Date"), the Securities will be redeemable, in whole but not in part, at a
Redemption Price equal to the sum of (a) an amount equal to 100% of the
principal amount thereof and (b) the Make-Whole Premium, together with accrued
and unpaid interest to the Redemption Date.  In no event will such redemption
price ever be less than 100% of the principal amount of the Securities plus
accrued interest to the Redemption Date.  On or after July 1, 2003, the
Securities will be redeemable, in whole or in part, at the Redemption Prices
(expressed as percentages of principal amount) set forth below, plus accrued and
unpaid interest, if any, to the Redemption Date (subject to the right of Holders
of record on the relevant record date to receive interest due on an Interest
Payment Date that is on or prior to the redemption date), if redeemed during the
12-month period beginning on July 1 of the years indicated below:

            Year                 Price
       2003                     104.188%
       2004                     102.792%
       2005                     101.396%
       2006 and thereafter      100.000%

In addition, at any time and from time to time prior to July 1, 2001, the
Company may, at its option, redeem in the aggregate up to 33 1/3% of the
aggregate principal amount of the Securities originally issued under this
Indenture with the proceeds of one or more Public Equity Offerings by the
Company at a redemption price (expressed as a percentage of principal amount) of
108.375%, plus accrued and unpaid interest, if any, to the date of redemption
(subject to the right of Holders on the relevant record date to receive interest
due on the relevant Interest Payment Date); provided, however, that at least
66-2/3% aggregate principal amount of the Securities originally issued under
this Indenture must remain outstanding after each such redemption. In order to
effect the foregoing redemption, the Company must mail notice of redemption no
later than 60 days after the related Public Equity Offering and must consummate
such redemption within 90 days of the closing of the Public Equity Offering.

     Section 11.2 Applicability of Article.  Redemption of Securities at the
election of the Company or otherwise, as permitted or required by any provision
of this Indenture, shall be made in accordance with such provision and this
Article.

     Section 11.3 Election to Redeem; Notice to Trustee.  The election of the
Company to redeem any Securities pursuant to Section 11.1 hereof shall be
evidenced by a Board Resolution.  In case of any redemption at the election of
the Company, the Company shall, at least 60 days prior to the Redemption Date
fixed by the Company (unless a shorter notice shall be satisfactory to the
Trustee), notify the Trustee of such Redemption Date and of the principal amount
of Securities to

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<PAGE>
 
be redeemed and shall deliver to the Trustee such documentation and records as
shall enable the Trustee to select the Securities to be redeemed pursuant to
Section 11.4 hereof.  Any election to redeem Securities shall be revocable until
the Company gives a notice of redemption pursuant to Section 11.5 hereof to the
Holders of Securities to be redeemed.

     Section 11.4 Selection by Trustee of Securities to Be Redeemed. In the
event that less than all of the Securities are to be redeemed at any time,
selection of such Securities (or any portion thereof that is an integral
multiple of $1,000) for redemption will be made by the Trustee from the
Outstanding Securities not previously called for redemption (or otherwise
purchased by the Company) on a pro rata basis, by lot or by such method as the
Trustee shall deem fair and appropriate; provided, however, that no Security
with a principal amount of $1,000 or less shall be redeemed in part.

     Section 11.5 Notice of Redemption. Notice of redemption shall be given in
the manner provided for in Section 15.5 hereof not less than 30 nor more than 60
days prior to the Redemption Date, to each Holder of Securities to be redeemed.

     All notices of redemption shall state:

          (a) the Redemption Date;

          (b) the Redemption Price;

          (c) if less than all Outstanding Securities are to be redeemed, the
identification (and in the case of a partial redemption, the principal amounts)
of the particular Securities to be redeemed;

          (d) that on the Redemption Date the Redemption Price (together with
accrued interest, if any, to the Redemption Date payable as provided in Section
11.7 hereof) will become due and payable upon each such Security, or the portion
thereof, to be redeemed, and that, unless the Company shall default in the
payment of the Redemption Price and any applicable accrued interest, interest
thereon will cease to accrue on and after said date; and

          (e) the place or places where such Securities are to be surrendered
for payment of the Redemption Price.

     Notice of redemption of Securities to be redeemed at the election of the
Company shall be given by the Company or, at the Company's request, by the
Trustee in the name and at the expense of the Company.  Failure to give such
notice by mailing to any Holder of Securities or any defect therein shall not
affect the validity of any proceedings for the redemption of other Securities.

     Section 11.6 Deposit of Redemption Price.  On or before 12:00 noon on any
Redemption Date, the Company shall deposit with the Trustee or with a Paying
Agent (or, if the Company is

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<PAGE>
 
acting as its own Paying Agent, segregate and hold in trust as provided in
Section 10.3 hereof) an amount of money sufficient to pay the Redemption Price
of, and accrued and unpaid interest on, all the Securities which are to be
redeemed on such Redemption Date.

     Section 11.7 Securities Payable on Redemption Date.   Notice of redemption
having been given as aforesaid, the Securities so to be redeemed shall, on the
Redemption Date, become due and payable at the Redemption Price therein
specified (together with accrued and unpaid interest, if any, to the Redemption
Date), and from and after such date (unless the Company shall default in the
payment of the Redemption Price and accrued and unpaid interest) such Securities
shall cease to bear interest.  Upon surrender of any such Security for
redemption in accordance with said notice, such Security shall be paid by the
Company at the Redemption Price, together with accrued and unpaid interest, if
any, to the Redemption Date; provided, however, that installments of interest
whose Stated Maturity is on or prior to the Redemption Date shall be payable to
the Holders of such Securities, or one or more Predecessor Securities,
registered as such at the close of business on the relevant Record Dates
according to their terms and the provisions of Section 3.9 hereof.

     If any Security called for redemption shall not be so paid upon surrender
thereof for redemption, the principal (and premium, if any) shall, until paid,
bear interest from the Redemption Date at the rate borne by the Securities.

     Section 11.8 Securities Redeemed in Part.  Any Security which is to be
redeemed only in part shall be surrendered at the office or agency of the
Company maintained for such purpose pursuant to Section 10.2 hereof (with, if
the Company or the Trustee so requires, due endorsement by, or a written
instrument of transfer in form satisfactory to the Company and the Trustee duly
executed by, the Holder thereof or such Holder's attorney duly authorized in
writing), and the Company shall execute, and the Trustee shall authenticate and
deliver to the Holder of such Security without service charge, a new Security or
Securities, of any authorized denomination as requested by such Holder, in
aggregate principal amount equal to and in exchange for the unredeemed portion
of the principal amount of the Security so surrendered.


                                  ARTICLE XII

                      DEFEASANCE AND COVENANT DEFEASANCE
                      ----------------------------------

     Section 12.1 Company's Option to Effect Defeasance or Covenant Defeasance.
The Company may, at its option by Board Resolution, at any time, with respect to
the Securities, elect to have either Section 12.2 or Section 12.3 hereof be
applied to all Outstanding Securities upon compliance with the conditions set
forth below in this Article XII.

     Section 12.2  Defeasance and Discharge.  Upon the Company's exercise under
Section 12.1 hereof of the option applicable to this Section 12.2, the Company
and the Subsidiary Guarantors shall be deemed to have been discharged from their
obligations with respect to all Outstanding

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<PAGE>
 
Securities on the date the conditions set forth in Section 12.4 hereof are
satisfied (hereinafter, "legal defeasance").  For this purpose, such legal
defeasance means that the Company and the Subsidiary Guarantors shall be deemed
(i) to have paid and discharged their respective obligations under the
Outstanding Securities; provided, however that the Securities shall continue to
be deemed to be "Outstanding" for purposes of Section 12.6 hereof and the other
Sections of this Indenture referred to in clauses (A) and (B) below, and (ii) to
have satisfied all their other obligations under such Securities and this
Indenture insofar as such Securities are concerned (and the Trustee, at the
expense of the Company, shall execute proper instruments acknowledging the
same), except for the following which shall survive until otherwise terminated
or discharged hereunder: (A) the rights of Holders of Outstanding Securities to
receive, solely from the trust fund described in Section 12.4 hereof and as more
fully set forth in such Section, payments in respect of the principal of (and
premium, if any, on) and interest on such Securities when such payments are due
(or at such time as the Securities would be subject to redemption at the option
of the Company in accordance with this Indenture), (B) the obligations of the
Company under Sections 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 5.8, 5.14, 6.6, 6.9, 6.10
and 10.2 hereof, (C) the rights, powers, trusts, duties and immunities of the
Trustee hereunder, and (D) the obligations of the Company under this Article
XII.  Subject to compliance with this Article XII, the Company may exercise its
option under this Section 12.2 notwithstanding the prior exercise of its option
under Section 12.3 hereof with respect to the Securities.

     Section 12.3 Covenant Defeasance. Upon the Company's exercise under Section
12.1 hereof of the option applicable to this Section 12.3, the Company and the
Subsidiary Guarantors shall be released from their obligations under any
covenant contained in Articles VIII and XIII and in Sections 10.5 through 10.19
hereof and the Defaults and Events of Default contained in Sections 5.1(e), (f),
(g) and (h) hereof with respect to the Outstanding Securities on and after the
date the conditions set forth below are satisfied (hereinafter, "covenant
defeasance"), and the Securities shall thereafter be deemed not to be
"Outstanding" for the purposes of any direction, waiver, consent or declaration
or Act of Holders (and the consequences of any thereof) in connection with such
covenants, Defaults and Events of Default, but shall continue to be deemed
"Outstanding" for all other purposes hereunder.  For this purpose, such covenant
defeasance means that, with respect to the Outstanding Securities, the Company
and the Subsidiary Guarantors may omit to comply with and shall have no
liability in respect of any term, condition or limitation set forth in any such
covenant, Default or Event of Default, whether directly or indirectly, by reason
of any reference elsewhere herein to any such provision or by reason of any
reference in any such provision to any other provision herein or in any other
document and such omission to comply shall not constitute a Default or an Event
of Default under Sections 5.1 (c), (d), (e), (f), (g) and (h) hereof, but,
except as specified above, the remainder of this Indenture and such Securities
shall be unaffected thereby.

     Section 12.4 Conditions to Legal Defeasance or Covenant Defeasance.  The
following shall be the conditions to application of either Section 12.2 or
Section 12.3 hereof to the Outstanding Securities:

          (a) The Company or any Subsidiary Guarantor shall irrevocably have
deposited or caused to be deposited with the Trustee (or another trustee
satisfying the requirements of Section

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6.7 hereof who shall agree to comply with the provisions of this Article XII
applicable to it) as trust funds in trust for the purpose of making the
following payments, specifically pledged as security for, and dedicated solely
to, the benefit of the Holders of such Securities, (A) cash in U.S. Dollars in
an amount, or (B) U.S. Government Obligations which through the scheduled
payment of principal and interest in respect thereof in accordance with their
terms will provide, not later than one day before the due date of any payment,
money in an amount, or (C) a combination thereof, sufficient, in the opinion of
a nationally recognized firm of independent public accountants expressed in a
written certification thereof delivered to the Trustee, to pay and discharge,
and which shall be applied by the Trustee (or other qualifying trustee) to pay
and discharge, the principal of (and premium, if any, on) and interest on the
Outstanding Securities on the Stated Maturity (or Redemption Date, if
applicable) of such principal (and premium, if any) or installment of interest;
provided that the Trustee shall have been irrevocably instructed in writing by
the Company to apply such money or the proceeds of such U.S. Government
Obligations to said payments with respect to the Securities.  Before such a
deposit, the Company may give to the Trustee, in accordance with Section 11.3
hereof, a notice of its election to redeem all of the Outstanding Securities at
a future date in accordance with Article XI hereof, which notice shall be
irrevocable.  Such irrevocable redemption notice, if given, shall be given
effect in applying the foregoing.  For this purpose, "U.S. Government
Obligations" means securities that are (x) direct obligations of the United
States of America for the timely payment of which its full faith and credit is
pledged or (y) obligations of a Person controlled or supervised by and acting as
an agency or instrumentality of the United States of America the timely payment
of which is unconditionally guaranteed as a full faith and credit obligation by
the United States of America, which, in either case, are not callable or
redeemable at the option of the issuer thereof, and shall also include a
depository receipt issued by a bank (as defined in Section 3(a)(2) of the
Securities Act of 1933, as amended), as custodian with respect to any such U.S.
Government Obligation or a specific payment of principal of or interest on any
such U.S. Government Obligation held by such custodian for the account of the
holder of such depository receipt, provided that (except as required by law)
such custodian is not authorized to make any deduction from the amount payable
to the holder of such depository receipt from any amount received by the
custodian in respect of the U.S. Government Obligation or the specific payment
of principal of or interest on the U.S. Government Obligation evidenced by such
depository receipt.

          (b) No Default or Event of Default with respect to the Securities
shall have occurred and be continuing on the date of such deposit.

          (c) Such legal defeasance or covenant defeasance shall not cause the
Trustee to have a conflicting interest under this Indenture or the Trust
Indenture Act with respect to any securities of the Company or any Subsidiary
Guarantor.

          (d) Such legal defeasance or covenant defeasance shall not result in a
breach or violation of, or constitute a default under any other material
agreement or instrument to which the Company or any Subsidiary Guarantor is a
party or by which it is bound, as evidenced to the Trustee in an Officers'
Certificate delivered to the Trustee concurrently with such deposit.

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          (e) In the case of an election under Section 12.2 hereof, the Company
shall have delivered to the Trustee an Opinion of Counsel stating that (i) the
Company has received from, or there has been published by, the Internal Revenue
Service a ruling, or (ii) since the Issue Date there has been a change in the
applicable Federal income tax laws; in either case providing that the Holders of
the Outstanding Securities will not recognize income, gain or loss for federal
income tax purposes as a result of such legal defeasance and will be subject to
federal income tax on the same amounts, in the same manner and at the same times
as would have been the case if such legal defeasance had not occurred (it being
understood that (x) such Opinion of Counsel shall also state that such ruling or
applicable law is consistent with the conclusions reached in such Opinion of
Counsel and (y) the Trustee shall be under no obligation to investigate the
basis of correctness of such ruling).

          (f) In the case of an election under Section 12.3 hereof, the Company
shall have delivered to the Trustee an Opinion of Counsel to the effect that the
Holders of the Outstanding Securities will not recognize income, gain or loss
for Federal income tax purposes as a result of such covenant defeasance and will
be subject to federal income tax on the same amounts, in the same manner and at
the same times as would have been the case if such covenant defeasance had not
occurred.

          (g) The Company shall have delivered to the Trustee an Officers'
Certificate and an Opinion of Counsel, which, taken together, state that all
conditions precedent provided for relating to either the legal defeasance under
Section 12.2 hereof or the covenant defeasance under Section 12.3 (as the case
may be) have been complied with and that no violations under agreements
governing any other outstanding Indebtedness would result therefrom.

     Section 12.5 Deposited Money and U.S. Government Obligations to Be Held in
Trust; Other Miscellaneous Provisions.  Subject to the provisions of the last
paragraph of Section 10.3 hereof, all money and U.S. Government Obligations
(including the proceeds thereof) deposited with the Trustee (or other qualifying
trustee--collectively for purposes of this Section 12.5, the "Trustee") pursuant
to Section 12.4 hereof in respect of the Outstanding Securities shall be held in
trust and applied by the Trustee, in accordance with the provisions of such
Securities and this Indenture, to the payment, either directly or through any
Paying Agent (including the Company acting as its own Paying Agent) as the
Trustee may determine, to the Holders of such Securities of all sums due and to
become due thereon in respect of principal (and premium, if any) and interest,
but such money need not be segregated from other funds except to the extent
required by law.

     The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the U.S. Government Obligations
deposited pursuant to Section 12.4 hereof or the principal and interest received
in respect thereof other than any such tax, fee or other charge which by law is
for the account of the Holders of the Outstanding Securities.

     Anything in this Article XII to the contrary notwithstanding, the Trustee
shall deliver or pay to the Company from time to time upon Company Request any
money or U.S. Government

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Obligations held by it as provided in Section 12.4 hereof which, in the opinion
of a nationally recognized firm of independent public accountants expressed in a
written certification thereof delivered to the Trustee, are in excess of the
amount thereof which would then be required to be deposited to effect an
equivalent legal defeasance or covenant defeasance, as applicable, in accordance
with this Article.

     Section 12.6 Reinstatement. If the Trustee or any Paying Agent is unable to
apply any money in accordance with Section 12.5 hereof by reason of any order or
judgment of any court or governmental authority enjoining, restraining or
otherwise prohibiting such application, then the Company's and the Subsidiary
Guarantors' obligations under this Indenture and the Securities shall be revived
and reinstated as though no deposit had occurred pursuant to Section 12.2 or
12.3 hereof, as the case may be, until such time as the Trustee or Paying Agent
is permitted to apply all such money in accordance with Section 12.5 hereof;
provided, however, that if the Company or any Subsidiary Guarantor makes any
payment of principal of (or premium, if any, on) or interest on any Security
following the reinstatement of its obligations, the Company or such Subsidiary
Guarantor shall be subrogated to the rights of the Holders of such Securities to
receive such payment from the money held by the Trustee or Paying Agent.


                                 ARTICLE XIII

                                  GUARANTEES
                                  ----------

     Section 13.1  Unconditional Guarantee.  Each Subsidiary Guarantor hereby
unconditionally, jointly and severally, guarantees (each such guarantee to be
referred to herein as a "Subsidiary Guarantee," with all such guarantees being
referred to herein as the "Subsidiary Guarantees") to each Holder of Securities
authenticated and delivered by the Trustee and to the Trustee and its successors
and assigns, the full and prompt performance of the Company's obligations under
this Indenture and the Securities and that:

          (a) the principal of (premium, if any, on) and interest on the
Securities will be promptly paid in full when due, whether at maturity, by
acceleration, redemption or otherwise, and interest on the overdue principal of
and interest on the Securities, if any, to the extent lawful, and all other
obligations of the Company to the Holders or the Trustee hereunder or thereunder
will be promptly paid in full or performed, all in accordance with the terms
hereof and thereof; and

          (b) in case of any extension of time of payment or renewal of any
Securities or of any such other obligations, the same will be promptly paid in
full when due or performed in accordance with the terms of the extension or
renewal, whether at Stated Maturity, by acceleration or otherwise;

subject, however, in the case of clauses (a) and (b) above, to the limitations
set forth in Section 13.4 hereof.

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<PAGE>
 
     Failing payment when due of any amount so guaranteed or any performance so
guaranteed for whatever reason, the Subsidiary Guarantors will be jointly and
severally obligated to pay the same immediately.  Each Subsidiary Guarantor
hereby agrees that its obligations hereunder shall be unconditional,
irrespective of the validity, regularity or enforceability of the Securities or
this Indenture, the absence of any action to enforce the same, any waiver or
consent by any Holder of the Securities with respect to any provisions hereof or
thereof, the recovery of any judgment against the Company, any action to enforce
the same or any other circumstance which might otherwise constitute a legal or
equitable discharge or defense of a guarantor.  Each Subsidiary Guarantor hereby
waives diligence, presentment, demand of payment, notice of acceleration, notice
of intent to accelerate, filing of claims with a court in the event of
insolvency or bankruptcy of the Company, any right to require a proceeding first
against the Company, protest, notice and all demands whatsoever and covenants
that its Subsidiary Guarantee will not be discharged except by complete
performance of the obligations contained in the Securities, this Indenture and
in this Subsidiary Guarantee.  If any Holder or the Trustee is required by any
court or otherwise to return to the Company, any Subsidiary Guarantor, or any
custodian, trustee, liquidator or other similar official acting in relation to
the Company or any Subsidiary Guarantor, any amount paid by the Company or any
Subsidiary Guarantor to the Trustee or such Holder, this Subsidiary Guarantee,
to the extent theretofore discharged, shall be reinstated in full force and
effect.  Each Subsidiary Guarantor agrees it shall not be entitled to any right
of subrogation in relation to the Holders in respect of any obligations
guaranteed hereby until payment in full of all obligations guaranteed hereby.
Each Subsidiary Guarantor further agrees that, as between each Subsidiary
Guarantor, on the one hand, and the Holders and the Trustee, on the other hand,
(x) the maturity of the obligations guaranteed hereby may be accelerated as
provided in Article V hereof for the purposes of this Subsidiary Guarantee,
notwithstanding any stay, injunction or other prohibition preventing such
acceleration in respect of the obligations guaranteed hereby, and (y) in the
event of any acceleration of such obligations as provided in Article V hereof,
such obligations (whether or not due and payable) shall forthwith become due and
payable by each Subsidiary Guarantor for the purpose of this Subsidiary
Guarantee.

     Section 13.2 Subsidiary Guarantors May Consolidate, etc., on Certain Terms.

          (a) Except as set forth in Articles VIII and X hereof, nothing
contained in this Indenture or in any of the Securities shall prevent any
consolidation or merger of a Subsidiary Guarantor with or into the Company or
another Subsidiary Guarantor or shall prevent any sale or conveyance of the
assets of a Subsidiary Guarantor as an entirety or substantially as an entirety,
to the Company or another Subsidiary Guarantor.

          (b) Except as set forth in Articles VIII and X hereof, nothing
contained in this Indenture or in any of the Securities shall prevent any
consolidation or merger of a Subsidiary Guarantor with or into a Person other
than the Company or a Subsidiary Guarantor (whether or not affiliated with the
Subsidiary Guarantor), or successive consolidations or mergers in which a
Subsidiary Guarantor or its successor or successors shall be a party or parties,
or shall prevent any sale or conveyance of the Properties of a Subsidiary
Guarantor as an entirety or substantially as an

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entirety, to a Person other than the Company or another Subsidiary Guarantor
(whether or not Affiliated with the Subsidiary Guarantor) authorized to acquire
and operate the same; provided, however, that, subject to Sections 13.2(a) and
13.3 hereof, (i) immediately after such transaction, and giving effect thereto,
no Default or Event of Default shall have occurred as a result of such
transaction and be continuing, (ii) such transaction shall not violate any of
the covenants in Sections 10.10 through 10.19 hereof, and (iii) each Subsidiary
Guarantor hereby covenants and agrees that, upon any such consolidation, merger,
sale or conveyance, such Subsidiary Guarantor's Subsidiary Guarantee set forth
in this Article XIII and in a notation to the Securities, and the due and
punctual performance and observance of all of the covenants and conditions of
this Indenture to be performed by such Subsidiary Guarantor, shall be expressly
assumed (in the event that the Subsidiary Guarantor is not the surviving
corporation in the merger), by supplemental indenture satisfactory in form to
the Trustee, executed and delivered to the Trustee, by such Person formed by
such consolidation, or into which the Subsidiary Guarantor shall have merged, or
by the Person that shall have acquired such Property (except to the extent the
following Section 13.3 would result in the release of such Subsidiary Guarantee
in which case such surviving Person does not have to execute any such
supplemental indenture).  In the case of any such consolidation, merger, sale or
conveyance and upon the assumption by the successor Person, by supplemental
indenture executed and delivered to the Trustee and satisfactory in form to the
Trustee of the due and punctual performance of all of the covenants and
conditions of this Indenture to be performed by the Subsidiary Guarantor, such
successor Person shall succeed to and be substituted for the Subsidiary
Guarantor with the same effect as if it had been named herein as a Subsidiary
Guarantor.

     Section 13.3 Release of a Subsidiary Guarantor. The Subsidiary Guarantee of
a Subsidiary Guarantor shall be automatically and unconditionally released and
discharged upon (i) any sale, exchange or transfer, to any Person that is not an
Affiliate of the Company, of all of the Company's Capital Stock in, or all or
substantially all the assets of such Subsidiary Guarantor (which sale, exchange
or transfer is not prohibited by this Indenture), (ii) the merger of such
Subsidiary Guarantor into the Company or any other Restricted Subsidiary
(provided the surviving Restricted Subsidiary assumes the Subsidiary Guarantee)
or the liquidation and dissolution of such Subsidiary Guarantor (in each case to
the extent not prohibited by this Indenture), or (iii) if applicable, the
release or discharge of the guarantee which resulted in the creation of such
Subsidiary Guarantee under Section 10.13 hereof, except a discharge or release
by or as a result of payment under such guarantee. If, at any time while any of
the Securities remain outstanding, none of the Company's then outstanding
Indebtedness (other than the Securities) is guaranteed by a Subsidiary
Guarantor, such Subsidiary Guarantor shall be automatically and unconditionally
released, discharged and relieved of any obligations under its Subsidiary
Guarantee (which shall be terminated and cease to have any force and effect).
Each Subsidiary Guarantor that is designated as an Unrestricted Subsidiary in
accordance with the provisions of this Indenture shall be released from its
Subsidiary Guarantee and related obligations set forth in this Indenture for so
long as it remains an Unrestricted Subsidiary. The Trustee shall deliver an
appropriate instrument evidencing such release upon receipt of a Company Request
accompanied by an Officers' Certificate and an Opinion of Counsel certifying
that such sale or other disposition was made by the Company in accordance with
the provisions of this Indenture. Any Subsidiary Guarantor not so released
remains liable for the full 

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amount of principal of (and premium, if any, on) and interest on the Securities
as provided in this Article XIII.

     Section 13.4 Limitation of Subsidiary Guarantor's Liability. Each
Subsidiary Guarantor, and by its acceptance hereof each Holder, hereby confirms
that it is the intention of all such parties that the Guarantee by such
Subsidiary Guarantor pursuant to its Subsidiary Guarantee not constitute a
fraudulent transfer or fraudulent conveyance for purposes of any federal, state
or foreign law. To effectuate the foregoing intention, the Holders and each
Subsidiary Guarantor hereby irrevocably agree that the obligations of each
Subsidiary Guarantor under its Subsidiary Guarantee shall be limited to the
maximum amount as will, after giving effect to all other contingent and fixed
liabilities (including, but not limited to, Guarantor Senior Indebtedness) of
such Subsidiary Guarantor and after giving effect to any collections from or
payments made by or on behalf of any other Subsidiary Guarantor in respect of
the obligations of such other Subsidiary Guarantor under its Subsidiary
Guarantee or pursuant to Section 13.5 hereof, result in the obligations of such
Subsidiary Guarantor under its Subsidiary Guarantee not constituting a
fraudulent conveyance or fraudulent transfer under federal, state or foreign
law. This Section 13.4 is for the benefit of the creditors of each Subsidiary
Guarantor.

     Section 13.5 Contribution.  In order to provide for just and equitable
contribution among the Subsidiary Guarantors, the Subsidiary Guarantors agree,
inter se, that in the event any payment or distribution is made by any
Subsidiary Guarantor (a "Funding Guarantor") under its Subsidiary Guarantee,
such Funding Guarantor shall be entitled to a contribution from each other
Subsidiary Guarantor (if any) in a pro rata amount based on the Adjusted Net
Assets of each Subsidiary Guarantor (including the Funding Guarantor) for all
payments, damages and expenses incurred by that Funding Guarantor in discharging
the Company's obligations with respect to the Securities or any other Subsidiary
Guarantor's obligations with respect to its Subsidiary Guarantee.

     Section 13.6 Execution and Delivery of Notation of Subsidiary Guarantee. To
evidence its Subsidiary Guarantee set forth in Section 13.1 hereof, each
Subsidiary Guarantor hereby agrees to execute the notation of Subsidiary
Guarantee in substantially the form set forth in Section 2.4 hereof to be
endorsed on each Security ordered to be authenticated and delivered by the
Trustee, and each Subsidiary Guarantor agrees that this Indenture shall be
executed on behalf of each Subsidiary Guarantor by its President or one of its
Vice Presidents and attested to by one of its Secretaries or Assistant
Secretaries. Each Subsidiary Guarantor hereby agrees that its Subsidiary
Guarantee set forth in Section 13.1 hereof shall remain in full force and effect
notwithstanding any failure to endorse on each Security a notation of such
Subsidiary Guarantee. Each such notation of Subsidiary Guarantee shall be signed
on behalf of each Subsidiary Guarantor by two Officers, or an Officer and an
Assistant Secretary or one Officer shall sign and one Officer or an Assistant
Secretary (each of whom shall, in each case, have been duly authorized by all
requisite corporate actions) shall attest to such notation of Subsidiary
Guarantee prior to the authentication of the Security on which it is endorsed,
and the delivery of such Security by the Trustee, after the authentication
thereof hereunder, shall constitute due delivery of the notation of Subsidiary
Guarantee set forth in this Indenture on behalf of the Subsidiary Guarantors.
Such signatures upon the notation of Subsidiary Guarantee may

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<PAGE>
 
be by manual or facsimile signature of such officers and may be imprinted or
otherwise reproduced on the Subsidiary Guarantee, and in case any such officer
who shall have signed the notation of Subsidiary Guarantee shall cease to be
such officer before the Security on which such notation of Subsidiary Guarantee
is endorsed shall have been authenticated and delivered by the Trustee or
disposed of by the Company, such Security nevertheless may be authenticated and
delivered or disposed of as though the person who signed the notation of
Subsidiary Guarantee had not ceased to be such officer of the Subsidiary
Guarantor.

     Section 13.7 Severability. In case any provision of this Subsidiary
Guarantee shall be invalid, illegal or unenforceable, that portion of such
provision that is not invalid, illegal or unenforceable shall remain in effect,
and the validity, legality, and enforceability of the remaining provisions shall
not in any way be affected or impaired thereby.

     Section 13.8 Subsidiary Guarantees Subordinated to Guarantor Senior
Indebtedness.   Each Subsidiary Guarantor covenants and agrees, and each Holder
of a Security, by his acceptance of the Subsidiary Guarantees, likewise
covenants and agrees, for the benefit of the holders, from time to time, of
Guarantor Senior Indebtedness, that the payments by such Subsidiary Guarantor in
respect of its Subsidiary Guarantee are subordinated and subject in right of
payment, to the extent and in the manner provided in this Article XIII, to the
prior payment in full of all Guarantor Senior Indebtedness of such Subsidiary
Guarantor, whether outstanding on the Issue Date or thereafter created,
incurred, assumed or guaranteed; provided, however, that the Subsidiary
Guarantee of such Subsidiary Guarantor, the Indebtedness represented thereby and
the payment of the principal of (and premium, if any, on) and the interest on
the Securities pursuant to such Subsidiary Guarantee in all respects shall rank
pari passu with, or prior to, all existing and future unsecured indebtedness
(including, without limitation, Indebtedness) of such Subsidiary Guarantor that
is subordinated to its Guarantor Senior Indebtedness.

     This Article XIII shall constitute a continuing offer to all Persons who,
in reliance upon such provisions, become holders of, or continue to hold,
Guarantor Senior Indebtedness, and such provisions are made for the benefit of
the holders of Guarantor Senior Indebtedness, and such holders are made obligees
hereunder and any of them may enforce such provisions.

     Section 13.9 Subsidiary Guarantors Not to Make Payments with Respect to
Subsidiary Guarantees in Certain Circumstances.

          (a) No payment or distribution of any Property of any Subsidiary
Guarantor of any kind or character (other than Permitted Guarantor Junior
Securities) may be made by such Subsidiary Guarantor in respect of its
Subsidiary Guarantee upon the happening of any default in respect of the payment
or required prepayment of any of its Guarantor Senior Indebtedness when the same
becomes due and payable (a "Subsidiary Guarantor Payment Default"), unless and
until such Subsidiary Guarantor Payment Default shall have been cured or waived
in writing or shall have ceased to exist or such Guarantor Senior Indebtedness
shall have been paid in full or otherwise

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<PAGE>
 
discharged, after which such Subsidiary Guarantor shall resume making any and
all required payments in respect of its Subsidiary Guarantee, including any
missed payments.

          (b) Upon the happening of any event (other than a Subsidiary Guarantor
Payment Default) the occurrence of which entitles one or more Persons to
accelerate the maturity of any Designated Guarantor Senior Indebtedness (a
"Subsidiary Guarantor Non-payment Default"), and receipt by the applicable
Subsidiary Guarantor and a Responsible Officer of the Trustee, on behalf of the
Trustee, of written notice thereof from one or more of the holders of such
Designated Guarantor Senior Indebtedness or their representative (a "Subsidiary
Guarantor Payment Notice"), then, unless and until such Subsidiary Guarantor
Non-payment Default shall have been cured or waived in writing or shall have
ceased to exist or such Designated Guarantor Senior Indebtedness is paid in full
or otherwise discharged or the holders (or a representative of the holders) of
such Designated Guarantor Senior Indebtedness give their written approval, no
payment or distribution shall be made by such Subsidiary Guarantor in respect of
its Subsidiary Guarantee (other than Permitted Guarantor Junior Securities);
provided, however, that these provisions will not prevent the making of any
payment for more than 179 days after a Subsidiary Guarantor Payment Notice shall
have been given after which, subject to Section 13.9(a), such Subsidiary
Guarantor will resume making any and all required payments in respect of its
Subsidiary Guarantee, including any missed payments.  Notwithstanding any other
provision of this Indenture, only one Subsidiary Guarantor Payment Notice shall
be given with respect to any Subsidiary Guarantee within any 360 consecutive day
period.  No Subsidiary Guarantor Non-payment Default with respect to Designated
Guarantor Senior Indebtedness that existed or was continuing on the date of any
Subsidiary Guarantor Payment Notice with respect to the Designated Guarantor
Senior Indebtedness initiating such Subsidiary Guarantor Payment Notice shall
be, or can be, made the basis for the commencement of a subsequent Subsidiary
Guarantor Payment Notice with respect to such Subsidiary Guarantee, whether or
not within a period of 360 consecutive days, unless such default shall have been
cured or waived for a period of not less than 90 consecutive days (it being
acknowledged that any subsequent action, or any breach of any financial covenant
for a period commencing after the date of commencement of such Subsidiary
Guarantor Payment Notice, that, in either case, would give rise to a Subsidiary
Guarantor Non-payment Default pursuant to any provision under which a Subsidiary
Guarantor Non-payment Default previously existed or was continuing shall
constitute a new Subsidiary Guarantor Non-payment Default for this purpose;
provided that, in the case of a breach of a particular financial covenant, such
Subsidiary Guarantor shall have been in compliance for at least one full 90
consecutive day period commencing after the date of commencement of such
Subsidiary Guarantor Payment Notice).  In no event shall a Subsidiary Guarantor
Payment Notice extend beyond 179 days from the date of its receipt and there
must be a 181 consecutive day period in any 360 consecutive day period during
which no Subsidiary Guarantor Payment Notice is in effect with respect to such
Subsidiary Guarantee.

          (c) In the event that, notwithstanding the foregoing, a Subsidiary
Guarantor shall make any payment in respect of its Subsidiary Guarantee to the
Trustee or the Holder of any Security prohibited by the foregoing provisions of
this Section 13.9, then and in such event such payment shall be paid over and
delivered forthwith to the Company.  In the event that a Subsidiary Guarantor

                                      112
<PAGE>
 
shall make any payment in respect of its Subsidiary Guarantee to the Trustee and
a Responsible Officer of the Trustee, on behalf of the Trustee, shall receive
written notice of a Subsidiary Guarantor Payment Default or a Subsidiary
Guarantor Non-payment Default from one or more of the holders of Guarantor
Senior Indebtedness (or their representative) prior to making any payment to
Holders in respect of the Subsidiary Guarantee and prior to 11:00 a.m. Eastern
Time on the date which is two Business Days prior to the date upon which by the
terms hereof any money may become payable for any purpose, such payments shall
be paid over by the Trustee and delivered forthwith to the Company.  Each
Subsidiary Guarantor shall give prompt written notice to the Trustee of any
default under any of its Guarantor Senior Indebtedness or under any agreement
pursuant to which its Guarantor Senior Indebtedness may have been issued.

     Section 13.10 Subsidiary Guarantees Subordinated to Prior Payment of All
Guarantor Senior Indebtedness upon Dissolution, etc.  Upon any distribution of
Properties of any Subsidiary Guarantor or payment on behalf of a Subsidiary
Guarantor in the event of any Insolvency or Liquidation Proceeding with respect
to such Subsidiary Guarantor:

          (a) the holders of such Subsidiary Guarantor's Guarantor Senior
Indebtedness shall be entitled to receive payment in full of such Guarantor
Senior Indebtedness, or provision must be made for such payment, before the
Holders are entitled to receive any direct or indirect payment or distribution
of any kind or character, whether in cash, property or securities (other than
Permitted Guarantor Junior Securities), on account of any payment in respect of
such Subsidiary Guarantor's Subsidiary Guarantee;

          (b) any direct or indirect payment or distribution of Properties of
such Subsidiary Guarantor of any kind or character, whether in cash, property or
securities (other than a payment or distribution in the form of Permitted
Guarantor Junior Securities), by set-off or otherwise, to which the Holders or
the Trustee, on behalf of the Holders, would be entitled except for the
provisions of this Article XIII, shall be paid by the Subsidiary Guarantor or by
any liquidating trustee or agent or other Person making such payment or
distribution, whether a trustee in bankruptcy, a receiver or liquidating trustee
or otherwise, directly to the holders of such Guarantor Senior Indebtedness or
their representative or representatives or to the trustee or trustees under any
indenture under which any instruments evidencing any of such Guarantor Senior
Indebtedness may have been issued, ratably according to the aggregate amounts
remaining unpaid on account of such Guarantor Senior Indebtedness held or
represented by each, to the extent necessary to make payment in full of all such
Guarantor Senior Indebtedness, after giving effect to any concurrent payment or
distribution to the holders of such Guarantor Senior Indebtedness; and

          (c) in the event that, notwithstanding the foregoing provisions of
this Section 13.10, any direct or indirect payment or distribution of Properties
of such Subsidiary Guarantor of any kind or character, whether in cash, property
or securities (other than a payment or distribution in the form of Permitted
Guarantor Junior Securities), shall be received by the Trustee or the Holders
before all such Guarantor Senior Indebtedness is paid in full or otherwise
discharged, such Properties shall be received and held in trust for and shall be
paid over to the holders of such

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Guarantor Senior Indebtedness remaining unpaid or their representatives, for
application to the payment of such Guarantor Senior Indebtedness until all such
Guarantor Senior Indebtedness shall have been paid or provided for in full,
after giving effect to any concurrent payment or distribution to the holders of
such Guarantor Senior Indebtedness.

     The Company or a Subsidiary Guarantor shall give prompt written notice to a
Responsible Officer of the Trustee, on behalf of the Trustee, of the occurrence
of any Insolvency or Liquidation Proceeding with respect to such Subsidiary
Guarantor.

     Section 13.11 Holders to be Subrogated to Rights of Holders of Guarantor
Senior Indebtedness. After the payment in full of all Guarantor Senior
Indebtedness of a Subsidiary Guarantor, the Holders shall be subrogated (equally
and ratably with the holders of all other Indebtedness of such Subsidiary
Guarantor which by its express terms is subordinated to such Guarantor Senior
Indebtedness to substantially the same extent as such Subsidiary Guarantee is so
subordinated and which is entitled to like rights of subrogation as a result of
payments made to the holders of such Guarantor Senior Indebtedness) to the
rights of the holders of such Guarantor Senior Indebtedness to receive payments
or distributions of cash, property and securities of such Subsidiary Guarantor
applicable to such Guarantor Senior Indebtedness until all amounts owing on the
Securities shall be paid in full, and for the purpose of such subrogation no
payments or distributions to the holders of such Guarantor Senior Indebtedness
by or on behalf of such Subsidiary Guarantor or by or on behalf of the Holders
by virtue of this Article XIII which otherwise would have been made to the
Holders shall, as between such Subsidiary Guarantor, its creditors other than
the holders of Guarantor Senior Indebtedness, and the Holders of the Securities,
be deemed to be a payment or distribution by such Subsidiary Guarantor to or on
account of such Guarantor Senior Indebtedness, it being understood that the
subordination provisions of this Article XIII are, and are intended solely for
the purpose of defining the relative rights of the Holders, on the one hand, and
the holders of Guarantor Senior Indebtedness, on the other hand.

     Section 13.12 Obligations of the Subsidiary Guarantors Unconditional.
Nothing contained in this Article XIII or elsewhere in this Indenture or in any
Security is intended to or shall impair, as between Subsidiary Guarantors and
the Holders, the obligation of the Subsidiary Guarantors under the Subsidiary
Guarantees, or is intended to or shall affect the relative rights of the Holders
and creditors of the Subsidiary Guarantors other than the holders of Guarantor
Senior Indebtedness, nor shall anything herein or therein prevent the Trustee or
any Holder from exercising all remedies otherwise permitted by applicable law
upon Default under this Indenture subject to the rights, if any, under this
Article XIII of the holders of Guarantor Senior Indebtedness in respect of cash,
property or securities of any Subsidiary Guarantor received upon the exercise of
any such remedy.  Upon any distribution of Properties of a Subsidiary Guarantor
referred to in this Article XIII, the Trustee, subject to the provisions of
Section 6.2 hereof, and the Holders of the Securities shall be entitled to rely
upon any order or decree made by any court of competent jurisdiction in which
such dissolution, winding up, liquidation or reorganization proceedings are
pending, or a certificate of a trustee in bankruptcy, receiver, liquidating
trustee, custodian, assignee for the benefit of creditors, or agent or other
Person making any distribution to the Trustee or to the Holders of the
Securities, for the

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purpose of ascertaining the Persons entitled to participate in such
distribution, the holders of the related Guarantor Senior Indebtedness and other
indebtedness of such Subsidiary Guarantor, the amount thereof or payable
thereon, the amount or amounts paid or distributed thereon and all other facts
pertinent thereto or to this Article XIII.

     Section 13.13 Trustee Entitled to Assume Payments Not Prohibited in Absence
of Notice. The Trustee shall not at any time be charged with knowledge of the
existence of any facts that would prohibit the making of any payment to or by
the Trustee, unless a Responsible Officer of the Trustee, on behalf of the
Trustee, shall have received at the Corporate Trust Office written notice
thereof from a Subsidiary Guarantor or from one or more holders of Guarantor
Senior Indebtedness or Designated Guarantor Senior Indebtedness, in the case of
a Subsidiary Guarantor Non-payment Default, or from any representative thereof;
and, prior to the receipt of any such written notice, the Trustee, subject to
TIA Sections 315(a) through 315(d), shall be entitled to assume conclusively
that no such facts exist. The Trustee shall be entitled to rely on the delivery
to it of a written notice by a Person representing himself to be a holder of
Guarantor Senior Indebtedness or Designated Guarantor Senior Indebtedness, in
the case of a Subsidiary Guarantor Non-payment Default (or a representative on
behalf of such holder), to establish that such notice has been given by a holder
of Guarantor Senior Indebtedness or Designated Guarantor Senior Indebtedness, in
the case of a Subsidiary Guarantor Non-payment Default, or a representative on
behalf of any such holder or holders.

     Section 13.14 Application by Trustee of Money Deposited with it.  Except as
provided in Article XIV, any deposit of money by a Subsidiary Guarantor with the
Trustee or any Paying Agent (whether or not in trust) for any payment in respect
of the related Subsidiary Guarantee shall be subject to the provisions of
Sections 13.8, 13.9, 13.10 and 13.11 hereof except that, if prior to 11:00 a.m.
Eastern time on the date which is two Business Days prior to the date on which
by the terms of this Indenture any such money may become payable for any
purpose, the Trustee or, in the case of any such deposit of money with a Paying
Agent, the Paying Agent shall not have received with respect to such money the
notice provided for in Section 13.13 hereof, then the Trustee or such Paying
Agent, as the case may be, shall have full power and authority to receive such
money and to apply the same to the purpose for which it was received, and shall
not be affected by any notice to the contrary which may be received by it on or
after 11:00 a.m., Eastern time, two Business Days prior to such payment date.
In the event that the Trustee determines in good faith that further evidence is
required with respect to the right of any Person as a holder of Guarantor Senior
Indebtedness to participate in any payment or distribution pursuant to this
Article XIII, the Trustee may request such Person to furnish evidence to the
reasonable satisfaction of the Trustee as to the amount of Guarantor Senior
Indebtedness held by such Person, the extent to which such Person is entitled to
participate in such payment or distribution and any other facts pertinent to the
rights of such Person under this Article XIII, and if such evidence is not
furnished, the Trustee may defer any payment to such Person pending judicial
determination as to the right of such Person to receive such payment.

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     The Trustee, however, shall not be deemed to owe any fiduciary duty to the
holders of Guarantor Senior Indebtedness but shall have only such obligations to
such holders as are expressly set forth in this Article XIII.

     Section 13.15 Subordination Rights Not Impaired by Acts of Omissions of
Subsidiary Guarantors or Holders of Guarantor Senior Indebtedness.  No right of
any present or future holders of any Guarantor Senior Indebtedness of a
Subsidiary Guarantor to enforce subordination as provided herein shall at any
time in any way be prejudiced or impaired by any act or failure to act on the
part of such Subsidiary Guarantor or by any act or failure to act by any such
holder, or by any noncompliance by such Subsidiary Guarantor with the terms of
this Indenture, regardless of any knowledge thereof which any such holder may
have or be otherwise charged with.

     Without in any way limiting the generality of the preceding paragraph of
this Section, the holders of Guarantor Senior Indebtedness may, at any time and
from time to time, without the consent of or notice to the Trustee or the
Holders of the Securities, without incurring responsibility to the Holders of
the Securities and without impairing or releasing the subordination or other
benefits provided in this Article, or the obligations hereunder of the Holders
of the Securities to the holders of Guarantor Senior Indebtedness, do any one or
more of the following: (1) change the manner, place or terms of payment or
extend the time of payment of, or renew, exchange, amend, increase or alter,
Guarantor Senior Indebtedness or the term of any instrument evidencing the same
or any agreement under which Guarantor Senior Indebtedness is outstanding or any
liability of any obligor thereon (unless such change, extension or alteration
results in such Indebtedness no longer being Guarantor Senior Indebtedness as
defined in this Indenture); (2) sell, exchange, release or otherwise deal with
any Property pledged, mortgaged or otherwise securing Guarantor Senior
Indebtedness; (3) settle or compromise any Guarantor Senior Indebtedness or any
liability of any obligor thereon or release any Person liable in any manner for
the collection of Guarantor Senior Indebtedness; and (4) exercise or refrain
from exercising any rights against the Company and any other Person.

     Section 13.16 Holders Authorize Trustee to Effectuate Subordination of
Subsidiary Guarantees.  Each Holder, by his acceptance thereof, authorizes and
expressly directs the Trustee on his behalf to take such action as may be
necessary or appropriate to effectuate the subordination provided in this
Article XIII and appoints the Trustee as his attorney-in-fact for such purpose,
including, in the event of any Insolvency or Liquidation Proceeding with respect
to any Subsidiary Guarantor, the immediate filing of a claim for the unpaid
balance of his Securities pursuant to the related Subsidiary Guarantee in the
form required in said proceedings and the causing of said claim to be approved.

     Section 13.17 Right of Trustee to Hold Guarantor Senior Indebtedness.  The
Trustee shall be entitled to all of the rights set forth in this Article XIII in
respect of any Guarantor Senior Indebtedness at any time held by it to the same
extent as any other holder of Guarantor Senior Indebtedness, and nothing in this
Indenture shall be construed to deprive the Trustee of any of its rights as such
holder.

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<PAGE>
 
     Section 13.18 Article XIII Not to Prevent Events of Default.  The failure
to make a payment on account of the Subsidiary Guarantees by reason of any
provision in this Article XIII shall not be construed as preventing the
occurrence of an Event of Default under this Indenture.

     Section 13.19 Payment.  For purposes of this Article XIII, a payment with
respect to any Subsidiary Guarantee or with respect to principal of or interest
on any Security or any Subsidiary Guarantee shall include, without limitation,
payment of principal of and interest on any Security, any depositing of funds
under Article IV hereof, any payment on account of any repurchase or redemption
of any Security and any payment or recovery on any claim (whether for rescission
or damages and whether based on contract, tort, duty imposed by law, or any
other theory of liability) relating to or arising out of the offer, sale or
purchase of any Security.


                                  ARTICLE XIV

                          SUBORDINATION OF SECURITIES
                          ---------------------------

     Section 14.1 Securities Subordinate to Senior Indebtedness.  The Company
covenants and agrees, and each Holder of a Security, by his acceptance thereof,
likewise covenants and agrees for the benefit of the holders, from time to time,
of Senior Indebtedness, that, to the extent and in the manner hereinafter set
forth in this Article XIV, the Indebtedness represented by the Securities and
the payment of and distributions of or with respect to the Obligations are
hereby expressly made subordinate and subject in right of payment as provided in
this Article to the prior payment in full in cash or cash equivalents of all
amounts payable under all existing and future Senior Indebtedness.

     This Article XIV shall constitute a continuing offer to all Persons who, in
reliance upon such provisions, become holders of, or continue to hold Senior
Indebtedness; and such provisions are made for the benefit of the holders of
Senior Indebtedness; and such holders are made obligees hereunder and they or
each of them may enforce such provisions.

     Section 14.2 Payment Over of Proceeds upon Dissolution, etc. In the event
of an Insolvency or Liquidation Proceeding with respect to the Company:

          (1) the holders of all Senior Indebtedness shall be entitled to
     receive payment in full in cash or cash equivalents of all Senior
     Indebtedness before the Holders of the Securities are entitled to receive
     any direct or indirect payment or distribution of any kind or character
     (excluding Permitted Junior Securities of the Company) on account of
     Obligations; and

          (2) any direct or indirect payment or distribution of assets of the
     Company of any kind or character, whether in cash, property or securities
     (excluding Permitted Junior Securities of the Company), by set-off or
     otherwise, to which the Holders or the Trustee would be entitled but for
     the provisions of this Article shall be paid by the liquidating trustee or
     agent or other Person making such payment or distribution, whether a
     trustee in

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<PAGE>
 
     bankruptcy, a receiver or liquidating trustee or otherwise, directly to the
     holders of Senior Indebtedness or their representative or representatives
     or to the trustee or trustees under any indenture under which any
     instruments evidencing any of such Senior Indebtedness may have been
     issued, ratably according to the aggregate amounts remaining unpaid on
     account of the Senior Indebtedness held or represented by each, to the
     extent necessary to make payment in full in cash or cash equivalents of all
     Senior Indebtedness remaining unpaid, after giving effect to any concurrent
     payment or distribution to the holders of such Senior Indebtedness; and

          (3) in the event that, notwithstanding the foregoing provisions of
     this Section 14.2, the Trustee or the Holder of any Security shall have
     received any payment or distribution of properties or assets of the Company
     of any kind or character, whether in cash, property or securities, by set
     off or otherwise, in respect of any Obligations before all Senior
     Indebtedness is paid or provided for in full, then and in such event such
     payment or distribution (excluding Permitted Junior Securities of the
     Company) shall be paid over or delivered forthwith to the trustee in
     bankruptcy, receiver, liquidating trustee, custodian, assignee, agent or
     other Person making payment or distribution of assets of the Company for
     application to the payment of all Senior Indebtedness remaining unpaid, to
     the extent necessary to pay all Senior Indebtedness in full, after giving
     effect to any concurrent payment or distribution to or for the holders of
     Senior Indebtedness.

     The consolidation of the Company with, or the merger of the Company with or
into, another Person or the liquidation or dissolution of the Company following
the conveyance, transfer or lease of its properties and assets substantially as
an entirety to another Person upon the terms and conditions set forth in Article
VIII hereof shall not be deemed a dissolution, winding-up, liquidation,
reorganization, assignment for the benefit of creditors or marshalling of assets
and liabilities of the Company for the purposes of this Article if the Person
formed by such consolidation or the surviving entity of such merger or the
Person which acquires by conveyance, transfer or lease such properties and
assets substantially as an entirety, as the case may be, shall, as a part of
such consolidation, merger, conveyance, transfer or lease, comply with the
conditions set forth in such Article VIII hereof to the extent applicable.

     Section 14.3 Suspension of Payment When Senior Indebtedness in Default.

          (a) Unless Section 14.2 hereof shall be applicable, upon the
occurrence of a Payment Default, no direct or indirect payment or distribution
of any assets of the Company of any kind or character shall be made by or on
behalf of the Company on account of the Obligations or on account of the
purchase or redemption or other acquisition of any Obligations unless and until
such Payment Default shall have been cured or waived or shall have ceased to
exist or such Designated Senior Indebtedness shall have been discharged or paid
in full in cash or Cash Equivalents, after which, subject to Section 14.2 hereof
(if applicable), the Company shall resume making any and all required payments
in respect of the Securities, and the other Obligations, including any missed
payments.

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          (b) Unless Section 14.2 hereof shall be applicable, upon (1) the
occurrence of a Non-payment Default and (2) receipt by the Trustee from a Senior
Representative of written notice (a "Payment Blockage Notice") of such
occurrence stating that such notice is a Payment Blockage Notice pursuant to
this Section 14.3(b) of this Indenture, no payment or distribution of any assets
of the Company of any kind or character shall be made by or on behalf of the
Company on account of any Obligations or on account of the purchase or
redemption or other acquisition of Obligations for a period ("Payment Blockage
Period") commencing on the date of receipt by the Trustee of such notice unless
and until the earlier to occur of the following events (subject to any blockage
of payments that may then be in effect under Section 14.2 hereof or subsection
(a) of this Section 14.3 hereof):  (w) 179 days shall have elapsed since receipt
of such written notice by the Trustee, (x) the date, as set forth in a written
notice to the Company or the Trustee from the Senior Representative initiating
such Payment Blockage Period, on which such Non-payment Default shall have been
cured or waived or shall have ceased to exist (provided that no other Payment
Default or Non-payment Default has occurred and is then continuing after giving
effect to such cure or waiver), (y) such Designated Senior Indebtedness shall
have been discharged or paid in full in cash or cash equivalents or (z) such
Payment Blockage Period shall have been terminated by written notice to the
Company or the Trustee from the Senior Representative initiating such Payment
Blockage Period, after which, subject to Sections 14.2 and 14.3(a) hereof (if
applicable), the Company shall promptly resume making any and all required
payments in respect of the Obligations, including any missed payments.
Notwithstanding any other provision of this Indenture, only one Payment Blockage
Period may be commenced within any 360 consecutive day period.  No Non-payment
Default with respect to Designated Senior Indebtedness that existed or was
continuing on the date of the commencement of any Payment Blockage Period with
respect to the Designated Senior Indebtedness initiating such Payment Blockage
Period shall be, or can be, made the basis for the commencement of a second
Payment Blockage Period, whether or not within a period of 360 consecutive days,
unless such default shall have been cured or waived for a period of not less
than 90 consecutive days (it being acknowledged that any subsequent action, or
any breach of any financial covenant for a period commencing after the date of
commencement of such Payment Blockage Period, that, in either case, would give
rise to a Non-payment Default pursuant to any provision under which a Non-
payment Default previously existed or was continuing shall constitute a new Non-
payment Default for this purpose; provided that, in the case of a breach of a
particular financial covenant, the Company shall have been in compliance for at
least one full 90 consecutive day period commencing after the date of
commencement of such Payment Blockage Period).  In no event shall a Payment
Blockage Period extend beyond 179 days from the date of the receipt of the
notice referred to in clause (2) hereof and there must be a 181 consecutive day
period in any 360 consecutive day period during which no Payment Blockage Period
is in effect pursuant to this Section 14.3(b).

          (c) In the event that, notwithstanding the foregoing, the Trustee or
the Holder of any Security shall have received any payment or distribution
prohibited by the foregoing provisions of this Section 14.3, then and in such
event such payment or distribution shall be paid over and delivered forthwith to
the Senior Representatives or as a court of competent jurisdiction shall direct
for application to the payment of any due and unpaid Senior Indebtedness, to the
extent necessary

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<PAGE>
 
to pay all such due and unpaid Senior Indebtedness in cash or cash equivalents,
after giving effect to any concurrent payment to or for the holders of Senior
Indebtedness.

     Section 14.4 Trustee's Relation to Senior Indebtedness. With respect to the
holders of Senior Indebtedness, notwithstanding any other provisions of this
Indenture, the Trustee undertakes to perform or to observe only such of its
covenants and obligations as are specifically set forth in this Article XIV, and
no implied covenants or obligations with respect to the holders of Senior
Indebtedness shall be read into this Indenture against the Trustee. The Trustee
shall not be deemed to owe any fiduciary duty to the holders of Senior
Indebtedness and the Trustee shall not be liable to any holder of Senior
Indebtedness if it shall mistakenly pay over or deliver to Holders, the Company
or any other Person moneys or assets to which any holder of Senior Indebtedness
shall be entitled by virtue of this Article XIV or otherwise.

     Section 14.5 Subrogation to Rights of Holders of Senior Indebtedness.  Upon
the payment in full in cash or Cash Equivalents of all Senior Indebtedness, the
Holders of the Securities shall be subrogated (equally and ratably with the
holders of all Indebtedness of the Company which by its express terms is
subordinated to Senior Indebtedness to substantially the same extent as the
Securities are so subordinated and which is entitled to like rights of
subrogation as a result of the payments made to the holders of Senior
Indebtedness) to the rights of the holders of such Senior Indebtedness to
receive payments and distributions of cash, property and securities applicable
to the Senior Indebtedness until the principal of, premium, if any, and interest
on the Securities shall be paid in full in cash or cash equivalents.  For
purposes of such subrogation, no payments or distributions to the holders of
Senior Indebtedness of any cash, property or securities to which the Holders of
the Securities or the Trustee would be entitled except for the provisions of
this Article XIV, and no payments over pursuant to the provisions of this
Article XIV to the holders of Senior Indebtedness by Holders of the Securities
or the Trustee shall, as among the Company, its creditors other than holders of
Senior Indebtedness, and the Holders of the Securities, be deemed to be payment
or distribution by the Company to or on account of the Senior Indebtedness.

     If any payment or distribution to which the Holders would otherwise have
been entitled but for the provisions of this Article XIV shall have been
applied, pursuant to the provisions of this Article XIV, to the payment of all
amounts payable under the Senior Indebtedness of the Company and such payments
or distributions received by such holders of such Senior Indebtedness shall be
in excess of the amount sufficient to pay all amounts payable under or in
respect of such Senior Indebtedness in full in cash or cash equivalents, then
and in such case the Holders shall be entitled to receive the amount of such
excess from the Company upon and to the extent of any return of such excess by
the holders of such Senior Indebtedness.

     Section 14.6 Provisions Solely To Define Relative Rights. The provisions of
this Article XIV are and are intended solely for the purpose of defining the
relative rights of the Holders of the Securities on the one hand and the holders
of Senior Indebtedness on the other hand. Nothing contained in this Article XIV
or elsewhere in this Indenture or in the Securities is intended to or shall (a)
impair, as among the Company, its creditors other than holders of Senior
Indebtedness and the

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<PAGE>
 
Holders of the Securities, the obligation of the Company, which is absolute and
unconditional, to pay to the Holders of the Securities the principal of,
premium, if any, and interest on the Securities as and when the same shall
become due and payable in accordance with their terms; or (b) affect the
relative rights against the Company of the Holders of the Securities and
creditors of the Company other than the holders of the Senior Indebtedness; or
(c) prevent the Trustee or the Holder of any Security from exercising all
remedies otherwise permitted by applicable law upon a Default or an Event of
Default under this Indenture, subject to the rights, if any, under this Article
XIV of the holders of Senior Indebtedness.

     The failure to make a payment on account of any Obligations by reason of
any provision of this Article XIV shall not be construed as preventing the
occurrence of a Default or an Event of Default hereunder.

     Section 14.7 Trustee To Effectuate Subordination. Each Holder of a Security
by his acceptance thereof authorizes and directs the Trustee on his behalf to
take such action as may be necessary or appropriate to effectuate the
subordination provided in this Article XIV and appoints the Trustee his 
attorney-in-fact for any and all such purposes, including, in the event of any
dissolution, winding-up, liquidation or reorganization of the Company whether in
bankruptcy, insolvency, receivership proceedings, or otherwise, the timely
filing of a claim for the unpaid balance of the Indebtedness of the Company
owing to such Holder in the form required in such proceedings and the causing of
such claim to be approved. If the Trustee does not file such a claim prior to 30
days before the expiration of the time to file such a claim, the holders of
Senior Indebtedness, or any Senior Representative, may file such a claim on
behalf of Holders of the Securities.

     Section 14.8 Waiver of Subordination Provision.

          (a) No right of any present or future holder of any Senior
Indebtedness to enforce subordination as herein provided shall at any time in
any way be prejudiced or impaired by any act or failure to act on the part of
the Company or by any act or failure to act, in good faith, by any such holder,
or by any non-compliance by the Company with the terms, provisions and covenants
of this Indenture, regardless of any knowledge thereof any such holder may have
or be otherwise charged with.

          (b) Without limiting the generality of subsection (a) of this Section
14.8, the holders of Senior Indebtedness may, at any time and from time to time,
without the consent of or notice to the Trustee or the Holders of the
Securities, without incurring responsibility to the Holders of the Securities
and without impairing or releasing the subordination provided in this Article
XIV or the obligations hereunder of the Holders of the Securities to the holders
of Senior Indebtedness, do any one or more of the following: (1) change the
manner, place or terms of payment or extend the time of payment of, or renew or
alter, Senior Indebtedness or any instrument evidencing the same or any
agreement under which Senior Indebtedness is outstanding or any liability of any
obligor thereon (unless such change, extension or alteration results in such
Indebtedness no longer being 

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Senior Indebtedness as defined in this Indenture); (2) sell, exchange, release
or otherwise deal with any property pledged, mortgaged or otherwise securing
Senior Indebtedness; (3) settle or compromise any Senior Indebtedness or any
liability of any obligor thereon or release any Person liable in any manner for
the collection or payment of Senior Indebtedness; and (4) exercise or refrain
from exercising any rights against the Company and any other Person; provided,
however, that in no event shall any such actions limit the right of the Holders
of the Securities to take any action to accelerate the maturity of the
Securities pursuant to Article V hereof or to pursue any rights or remedies
hereunder or under applicable laws if the taking of such action does not
otherwise violate the terms of this Indenture.

     Section 14.9  Notice to Trustee.

          (a) The Company shall give prompt written notice to the Trustee of any
fact known to the Company which would prohibit the making of any payment to or
by the Trustee in respect of the Securities.  Notwithstanding the provisions of
this Article XIV or any other provision of this Indenture, the Trustee shall not
be charged with knowledge of the existence of any facts which would prohibit the
making of any payment to or by the Trustee in respect of the Securities, unless
and until a Responsible Officer of the Trustee, on behalf of the Trustee, shall
have received written notice thereof from the Company or a holder of Senior
Indebtedness or from any trustee, fiduciary or agent therefor; and, prior to the
receipt of any such written notice, the Trustee, subject to the provisions of
this Section 14.9, shall be entitled in all respects to assume that no such
facts exist; provided, however, that if the Trustee shall not have received the
notice provided for in this Section 14.9 at least two Business Days prior to the
date upon which by the terms hereof any money may become payable for any purpose
under this Indenture (including, without limitation, the payment of the
principal of, premium, if any, or interest on any Security), then, anything
herein contained to the contrary notwithstanding but without limiting the rights
and remedies of the holders of Senior Indebtedness or any trustee, fiduciary or
agent thereof, the Trustee shall have full power and authority to receive such
money and to apply the same to the purpose for which such money was received and
shall not be affected by any notice to the contrary which may be received by it
within two Business Days prior to such date; nor shall the Trustee be charged
with knowledge of the curing of any such default or the elimination of the act
or condition preventing any such payment unless and until the Trustee shall have
received an Officers' Certificate to such effect.

          (b) Subject to TIA Sections 315(a) through 315(d), the Trustee shall
be entitled to rely on the delivery to it of a written notice to a Responsible
Officer of the Trustee, on behalf of the Trustee, by a Person representing
himself to be a holder of Senior Indebtedness (or a trustee, fiduciary or agent
therefor) to establish that such notice has been given by a holder of Senior
Indebtedness (or a trustee, fiduciary or agent therefor). In the event that the
Trustee determines in good faith that further evidence is required with respect
to the right of any Person as a holder of Senior Indebtedness to participate in
any payment or distribution pursuant to this Article XIV, the Trustee may
request such Person to furnish evidence to the reasonable satisfaction of the
Trustee as to the amount of Senior Indebtedness held by such Person, the extent
to which such Person is entitled to participate in such payment or distribution
and any other facts pertinent to the rights of such 

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Person under this Article XIV, and if such evidence is not furnished, the
Trustee may defer any payment to such Person pending judicial determination as
to the right of such Person to receive such payment.

     Section 14.10 Reliance on Judicial Order or Certificate of Liquidating
Agent. Upon any payment or distribution of assets of the Company referred to in
this Article XIV, the Trustee, subject to TIA Sections 315(a) through 315(d),
and the Holders, shall be entitled to rely upon any order or decree entered by
any court of competent jurisdiction in which such insolvency, bankruptcy,
receivership, liquidation, reorganization, dissolution, winding-up or similar
case or proceeding is pending, or a certificate of the trustee in bankruptcy,
receiver, liquidating trustee, custodian, assignee for the benefit of creditors,
agent or other Person making such payment or distribution, delivered to the
Trustee or to the Holders, for the purpose of ascertaining the Persons entitled
to participate in such payment or distribution, the holders of Senior
Indebtedness and other Indebtedness of the Company, the amount thereof or
payable thereon, the amount or amounts paid or distributed thereon and all other
facts pertinent thereto or to this Article XIV.

     Section 14.11 Rights of Trustee as Holder of Senior Indebtedness;
Preservation of Trustee's Rights. The Trustee in its individual capacity shall
be entitled to all the rights set forth in this Article XIV with respect to any
Senior Indebtedness which may at any time be held by it, to the same extent as
any other holder of Senior Indebtedness, and nothing in this Indenture shall
deprive the Trustee of any of its rights as such holder. Nothing in this Article
XIV shall apply to claims of, or payments to, the Trustee under or pursuant to
Section 6.6 hereof.

     Section 14.12 Article Applicable to Paying Agents. In case at any time any
Paying Agent other than the Trustee shall have been appointed by the Company and
be then acting hereunder, the term "Trustee" as used in this Article XIV shall
in such case (unless the context otherwise requires) be construed as extending
to and including such Paying Agent within its meaning as fully for all intents
and purposes as if such Paying Agent were named in this Article XIV in addition
to or in place of the Trustee; provided, however, that Section 14.11 hereof
shall not apply to the Company or any Affiliate of the Company if it or such
Affiliate acts as Paying Agent.

     Section 14.13 No Suspension of Remedies. Nothing contained in this Article
XIV shall limit the right of the Trustee or the Holders of Securities to take
any action to accelerate the maturity of the Securities pursuant to Article V
hereof or to pursue any rights or remedies hereunder or under applicable law,
subject to the rights, if any, under this Article XIV of the holders, from time
to time, of Senior Indebtedness.

                                      123
<PAGE>
 
                                  ARTICLE XV

                                 MISCELLANEOUS
                                 -------------

     Section 15.1 Compliance Certificates and Opinions.  Upon any application or
request by the Company and/or any Subsidiary Guarantor to the Trustee to take
any action under any provision of this Indenture, the Company and/or such
Subsidiary Guarantor, as the case may be, shall furnish to the Trustee such
certificates and opinions as may be required under the Trust Indenture Act or
this Indenture.  Each such certificate and each such opinion shall be in the
form of an Officers' Certificate or an Opinion of Counsel, as applicable, and
shall comply with the requirements of this Indenture.

     Every certificate or opinion with respect to compliance with a condition or
covenant provided for in this Indenture shall include:

              (1) a statement that each individual signing such certificate or
     opinion has read such covenant or condition and the definitions herein
     relating thereto;

              (2) a brief statement as to the nature and scope of the
     examination or investigation upon which the statements or opinions
     contained in such certificate or opinion are based;

              (3) a statement that, in the opinion of each such individual, he
     has made such examination or investigation as is necessary to enable him to
     express an informed opinion as to whether or not such covenant or condition
     has been complied with; and

              (4) a statement as to whether, in the opinion of each such
     individual, such condition or covenant has been complied with.

The certificates and opinions provided pursuant to this Section 15.1 and the
statements required by this Section 15.1 shall comply in all respects with TIA
Sections 314(c) and (e).

     Section 15.2 Form of Documents Delivered to Trustee.  In any case where
several matters are required to be certified by, or covered by an opinion of,
any specified Person, it is not necessary that all such matters be certified by,
or covered by the opinion of, only one such Person, or that they be so certified
or covered by only one document, but one such Person may certify or give an
opinion with respect to some matters and one or more other such Persons as to
other matters, and any such Person may certify or give an opinion as to such
matters in one or several documents.

     Any certificate or opinion of an Officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to the matters upon which his certificate or opinion is based are

                                      124
<PAGE>
 
erroneous.  Any such Opinion of Counsel may be based, insofar as it relates to
factual matters, upon an Officers' Certificate of an Officer or Officers of the
Company stating that the information with respect to such factual matters is in
the possession of the Company, unless such counsel knows, or in the exercise of
reasonable care should know, that the certificate with respect to such matters
is erroneous.

     Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form one instrument.

     Section 15.3 Acts of Holders.

          (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agents duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments are delivered
to the Trustee and, where it is hereby expressly required, to the Company. Such
instrument or instruments (and the action embodied therein and evidenced
thereby) are herein sometimes referred to as the "Act" of the Holders signing
such instrument or instruments. Proof of execution of any such instrument or of
a writing appointing any such agent shall be sufficient for any purpose of this
Indenture and conclusive in favor of the Trustee and the Company, if made in the
manner provided in this Section.

          (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary public or other officer authorized by
law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to him the execution thereof.  Where
such execution is by a signer acting in a capacity other than his individual
capacity, such certificate or affidavit shall also constitute sufficient proof
of authority.  The fact and date of the execution of any such instrument or
writing, or the authority of the Person executing the same, may also be proved
in any other manner which the Trustee deems sufficient.

          (c) The ownership, principal amount and serial numbers of Securities
held by any Person, and the date of holding the same, shall be proved by the
Security Register.

          (d) If the Company shall solicit from the Holders of Securities any
request, demand, authorization, direction, notice, consent, waiver or other Act,
the Company may, at its option, by or pursuant to a Board Resolution, fix in
advance a record date for the determination of Holders entitled to give such
request, demand, authorization, direction, notice, consent, waiver or other Act,
but the Company shall have no obligation to do so.  Notwithstanding TIA Section
316(c), such record date shall be the record date specified in or pursuant to
such Board Resolution, which shall be a date not earlier than the date 30 days
prior to the first solicitation of Holders generally in connection therewith and
not later than the date such solicitation is completed.  If such a record date

                                      125
<PAGE>
 
is fixed, such request, demand, authorization, direction, notice, consent,
waiver or other Act may be given before or after such record date, but only the
Holders of record at the close of business on such record date shall be deemed
to be Holders for the purposes of determining whether Holders of the requisite
proportion of Outstanding Securities have authorized or agreed or consented to
such request, demand, authorization, direction, notice, consent, wavier or other
Act, and for that purpose the Outstanding Securities shall be computed as of
such record date; provided that no such authorization, agreement or consent by
the Holders on such record date shall be deemed effective unless it shall become
effective pursuant to the provisions of this Indenture not later than eleven
months after the record date.

          (e) Any request, demand, authorization, direction, notice, consent,
waiver or other Act of the Holder of any Security shall bind every future Holder
of the same Security and the Holder of every Security issued upon the
registration of transfer thereof or in exchange therefor or in lieu thereof in
respect of anything done, omitted or suffered to be done by the Trustee or the
Company in reliance thereon, whether or not notation of such action is made upon
such Security.

     Section 15.4 Notices, etc. to Trustee, Company and Subsidiary Guarantors.
Any request, demand, authorization, direction, notice, consent, waiver or Act of
Holders or other document provided or permitted by this Indenture to be made
upon, given or furnished to, or filed with,

              (1) the Trustee by any Holder or by the Company or any Subsidiary
     Guarantor shall be sufficient for every purpose hereunder if made, given,
     furnished or filed in writing and delivered in person or mailed by
     certified or registered mail (return receipt requested) to the Trustee at
     its Corporate Trust Office; or

              (2) the Company or any Subsidiary Guarantor by the Trustee or by
     any Holder shall be sufficient for every purpose hereunder (unless
     otherwise herein expressly provided) if in writing and delivered in person
     or mailed by certified or registered mail (return receipt requested) to the
     Company addressed to it or a Subsidiary Guarantor, as applicable, at the
     Company's principal office located at 1201 Louisiana, Suite 1400, Houston,
     Texas 77002, or at any other address otherwise furnished in writing to the
     Trustee by the Company.

     Section 15.5 Notice to Holders; Waiver.  Where this Indenture provides for
notice of any event to Holders by the Company or the Trustee, such notice shall
be sufficiently given (unless otherwise herein expressly provided) if in writing
and mailed, first-class postage prepaid, to each Holder affected by such event,
at his address as it appears in the Security Register, not later than the latest
date, and not earlier than the earliest date, prescribed for the giving of such
notice.  In any case where notice to Holders is given by mail, neither the
failure to mail such notice, nor any defect in any notice so mailed, to any
particular Holder shall affect the sufficiency of such notice with respect to
other Holders.  Any notice mailed to a Holder in the manner herein prescribed
shall be conclusively deemed to have been received by such Holder, whether or
not such Holder actually receives such notice.  Where this Indenture provides
for notice in any manner, such notice may be waived in writing by the Person
entitled to receive such notice, either before or after the event, and

                                      126
<PAGE>
 
such waiver shall be the equivalent of such notice.  Waivers of notice by
Holders shall be filed with the Trustee, but such filing shall not be a
condition precedent to the validity of any action taken in reliance upon such
waiver.

     In case by reason of the suspension of or irregularities in regular mail
service or by reason of any other cause, it shall be impracticable to mail
notice of any event to Holders when such notice is required to be given pursuant
to any provision of this Indenture, then any manner of giving such notice as
shall be satisfactory to the Trustee shall be deemed to be a sufficient giving
of such notice for every purpose hereunder.

     Section 15.6 Effect of Headings and Table of Contents.  The Article and
Section headings herein and the Table of Contents are for convenience only and
shall not affect the construction hereof.

     Section 15.7 Successors and Assigns.  All covenants and agreements in this
Indenture by the Company and the Subsidiary Guarantors shall bind their
respective successors and assigns, whether so expressed or not.  All agreements
of the Trustee in this Indenture shall bind its successor.

     Section 15.8 Separability Clause. In case any provision in this Indenture
or in the Securities or the Subsidiary Guarantees shall be invalid, illegal or
unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby, and a Holder
shall have no claim therefore against any party hereto.

     Section 15.9 Benefits of Indenture. Nothing in this Indenture or in the
Securities, express or implied, shall give to any Person (other than the parties
hereto, any Paying Agent, any Securities Registrar and their successors
hereunder, the Holders, the holders of Senior Indebtedness, the holders of
Guarantor Senior Indebtedness and, to the extent set forth in Section 13.4
hereof, creditors of Subsidiary Guarantors) any benefit or any legal or
equitable right, remedy or claim under this Indenture.

     Section 15.10  Governing Law; Trust Indenture Act Controls.

     (a)  THIS INDENTURE, INCLUDING THE SUBSIDIARY GUARANTEES CONTAINED HEREIN,
AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW
OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAWS.
THE COMPANY AND EACH SUBSIDIARY GUARANTOR IRREVOCABLY SUBMITS TO THE NON-
EXCLUSIVE JURISDICTION OF ANY UNITED STATES FEDERAL OR NEW YORK STATE COURT
SITTING IN THE BOROUGH OF MANHATTAN, THE CITY OF NEW YORK IN ANY ACTION OR
PROCEEDING ARISING OUT OF OR RELATING TO THIS INDENTURE OR THE SECURITIES, AND
THE COMPANY AND EACH SUBSIDIARY GUARANTOR IRREVOCABLY AGREE THAT ALL CLAIMS IN
RESPECT OF SUCH

                                      127
<PAGE>
 
ACTION OR PROCEEDING MAY BE HEARD AND DETERMINED BY ANY SUCH COURT.

     (b)  This Indenture is subject to the provisions of the Trust Indenture Act
of 1939, as amended, that are required to be part of this Indenture and shall,
to the extent applicable, be governed by such provisions.  If and to the extent
that any provision of this Indenture limits, qualifies or conflicts with the
duties imposed by Sections 310 and 318, inclusive, of the Trust Indenture Act,
or conflicts with any provision (an "incorporated provision") required by or
deemed to be included in this Indenture by operation of such Trust Indenture Act
sections, such imposed duties or incorporated provision shall control.  If any
provision of this Indenture modifies or excludes any provision of the Trust
Indenture Act that may be so modified or excluded, the latter provision shall be
deemed to apply to this Indenture as so modified or excluded, as the case may
be.

     Section 15.11 Legal Holidays. In any case where any Interest Payment Date,
Redemption Date, or Stated Maturity or Maturity of any Security shall not be a
Business Day, then (notwithstanding any other provision of this Indenture or of
the Securities) payment of interest or principal (and premium, if any) need not
be made on such date, but may be made on the next succeeding Business Day with
the same force and effect as if made on the Interest Payment Date, Redemption
Date or at the Stated Maturity or Maturity; provided that no interest shall
accrue for the period from and after such Interest Payment Date, Redemption
Date, Stated Maturity or Maturity, as the case may be.

     Section 15.12 No Recourse Against Others. A director, officer,
incorporator, employee, Affiliate or stockholder of the Company or any
Subsidiary Guarantor, as such, shall not have any personal liability under the
Securities or this Indenture by reason of his or its status as such director,
officer, incorporator or stockholder. Each Holder, by accepting a Security with
the notation of Subsidiary Guarantee endorsed thereon, waives and releases all
such liability. Such waiver and release are part of the consideration for the
issuance of the Securities with the notation of Subsidiary Guarantee endorsed
thereon.

     Section 15.13 Duplicate Originals. The parties may sign any number of
copies or counterparts of this Indenture. Each signed copy shall be an original,
but all of them together represent the same agreement.

     Section 15.14 No Adverse Interpretation of Other Agreements. This Indenture
may not be used to interpret another indenture, loan or debt agreement of the
Company or any of its Subsidiaries. Any such indenture, loan or debt agreement
may not be used to interpret this Indenture.

                                     * * *
                            (Signature Page Follows)

                                      128
<PAGE>
 
   IN WITNESS WHEREOF, the parties hereto have caused this Indenture to be duly
executed as of the day and year first above written.


                                 ISSUER:

                                 OCEAN ENERGY, INC.,
                                 a Delaware corporation


                                 By:______________________________________
                                    Name:_________________________________
                                    Title:________________________________


                                 SUBSIDIARY GUARANTOR:

                                 OCEAN ENERGY, INC.,
                                 a Louisiana corporation


                                 By:______________________________________
                                    Name:_________________________________
                                    Title:________________________________


                                 TRUSTEE:

                                 U.S. BANK TRUST,
                                 NATIONAL ASSOCIATION, as Trustee


                                 By:______________________________________
                                    Name:_________________________________
                                    Title:________________________________
<PAGE>
 
                                                                       EXHIBIT A

                   CERTIFICATE TO BE DELIVERED UPON EXCHANGE
                   OR REGISTRATION OF TRANSFER OF SECURITIES

Re: 8-3/8% Series [A/B] Senior Subordinated Notes due 2008 of Ocean Energy, Inc.
     (the "Company")

          This Certificate relates to $____________ principal amount of
Securities held in *__________ book-entry or *_______________ definitive form by
________________________________________ (the "Transferor").


The Transferor*:

     [ ]  has requested the Trustee by written order to deliver in exchange for
its beneficial interest in the Global Securities held by the Depositary, a
Security or Securities in definitive registered form equal to its beneficial
interest in such Global Securities (or the portion thereof indicated above); or

     [ ]  has requested the Trustee by written order to exchange or register the
transfer of a Security or Securities.

          In connection with such request and in respect of each such Security,
the Transferor does hereby certify that the Transferor is familiar with the
Indenture relative to the above captioned Securities and that the transfer of
this Security does not require registration under the Securities Act (as defined
below) because:*

     [ ]  Such Security is being acquired for the Transferor's own account
without transfer.

     [ ]  Such Security is being transferred (i) to a "qualified institutional
buyer" (as defined in Rule 144A under the Securities Act of 1933, as amended
(the "Securities Act")), in reliance on Rule 144A under the Securities Act or
(ii) pursuant to an exemption from registration in accordance with Rule 904
under the Securities Act (and in the case of clause (ii), based on an opinion of
counsel if the Company so requests and together with a certification in
substantially the form of Exhibit C to the Indenture).

     [ ]  Such Security is being transferred (i) in accordance with Rule 144
under the Securities Act (and based on an opinion of counsel if the Company so
requests) or (ii) pursuant to an effective registration statement under the
Securities Act.

__________________
     *    Check appropriate box.

                                      A-1
<PAGE>
 
     [ ]  Such Security is being transferred to an institutional "accredited
investor" within the meaning of Rule 501(a)(1), (2), (3) or (7) under the
Securities Act pursuant to a private placement exemption from the registration
requirements of the Securities Act (and based on an opinion of counsel if the
Company so requests) together with a certification in substantially the form of
Exhibit B to the Indenture and, to the knowledge of the Transferor, such
institutional accredited investor to whom such Security is to be transferred is
not an "affiliate" (as defined in Rule 144 under the Securities Act) of the
Company.

     [ ]  Such Security is being transferred in reliance on and in compliance
with another exemption from the registration requirements of the Securities Act
(and based on an opinion of counsel if the Company so requests).


                                 ------------------------------------
                                 [INSERT NAME OF TRANSFEROR]

                                 By:__________________________________
                                     Name:____________________________
                                     Title:___________________________
                                     Address:_________________________


Date:_____________________

                                      A-2
<PAGE>
 
                                                                       EXHIBIT B


                      TRANSFEREE LETTER OF REPRESENTATIONS

Ocean Energy Inc.
1201 Louisiana
Suite 1400
Houston, Texas  77002

Dear Sirs and Madams:

     In connection with our proposed purchase of  $
million aggregate principal amount of 8-3/8% Senior Subordinated Notes due 2008
(the "Securities") of Ocean Energy, Inc., a Delaware corporation (the
"Company"):

          1.  We understand that the Securities have not been registered under
     the Securities Act of 1933, as amended (the "Securities Act"), or under any
     other applicable securities laws, and may not be sold except as permitted
     in the following sentence.  We agree on our own behalf and on behalf of any
     investor account for which we are purchasing the Securities to offer, sell
     or otherwise transfer such Securities prior to the date which is two years
     after the later of the date of original issue and the last date on which
     the Company or any affiliate of the Company was the owner of such
     Securities, or any predecessor, thereto (the "Resale Restriction
     Termination Date") only (a) to the Company, (b) pursuant to a registration
     statement that has been declared effective by the Securities and Exchange
     Commission (the "SEC"), (c) for so long as the Securities are eligible for
     resale pursuant to Rule 144A under the Securities Act, to a person we
     reasonably believe is a qualified institutional buyer under Rule 144A (a
     "QIB") that purchases for its own account or for the account of a QIB to
     whom notice is given that the transfer is being made in reliance on Rule
     144A, (d) pursuant to offers and sales to non-U.S. persons that occur
     outside the United States pursuant to Regulation S under the Securities
     Act, (e) to an institutional "accredited investor" within the meaning of
     subparagraph (a)(1), (2), (3) or (7) of Rule 501 under the Securities Act
     (an "Institutional Accredited Investor") that is acquiring the Securities
     for its own account or for the account of another Institutional Accredited
     Investor for investment purposes and not with a view to, or for offer or
     sale in connection with, any distribution thereof in violation of the
     regulations of the Securities Act and any other applicable securities laws
     or (f) pursuant to any other available exemption from the registration
     requirements of the Securities Act, subject in each of the foregoing cases
     to any requirement of law that the disposition of our property and the
     property of such investor account or accounts be at all times within our or
     their control.  The foregoing restrictions on resale will not apply
     subsequent to the Resale Restriction Termination Date.  If any resale or
     other transfer of the Securities is proposed to be made pursuant to clause
     (e) above prior to the Resale Restriction Termination Date, the transferor
     shall deliver a letter from the transferee substantially in the

                                      B-1
<PAGE>
 
     form of this letter to the Trustee, which shall provide, among other
     things, that the transferee is an Institutional Accredited Investor and
     that it is acquiring such Securities for investment purposes and not for
     distribution in violation of the Securities Act.  We acknowledge that the
     Company and the Trustee reserve the right prior to any offer, sale or other
     transfer pursuant to clauses (e) or (f) prior to the Resale Restriction
     Termination Date of the Securities to require the delivery of an opinion of
     counsel, certifications and/or other information satisfactory to the
     Company and the Trustee.

          2.  We are an Institutional Accredited Investor purchasing for our own
     account or for the account of another Institutional Accredited Investor.

          3.  We are acquiring the Securities purchased by us for our own
     account, or for one or more accounts as to each of which we exercise sole
     investment discretion, for investment purposes and not with a view to, or
     for offer or sale in connection with any distribution in violation of, the
     Securities Act.  We have such knowledge and experience in financial and
     business matters as to be capable of evaluating the merits and risks of
     investment in the Securities, we invest in securities similar to the
     Securities in the normal course of our business and we, and all accounts
     for which we are acting, are able to bear the economic risk of investment
     in the Securities.

          4.  You are entitled to rely upon this letter and you are irrevocably
     authorized to produce this letter or a copy hereof to any interested party
     in any administrative or legal proceeding or official inquiry with respect
     to the matters covered hereby.

                                 Very truly yours,


                                 By:___________________________________
                                            (Name of Purchaser)

Upon transfer, the Securities should be registered in the name of the new
beneficial owner as follows:

Name:_______________________________

Address:____________________________
       
        ____________________________ 
        ____________________________ 
        ____________________________ 

Taxpayer ID Number:_________________

                                      B-2
<PAGE>
 
                                                                       EXHIBIT C

               FORM OF CERTIFICATE TO BE DELIVERED IN CONNECTION
                    WITH TRANSFERS PURSUANT TO REGULATION S

                                                                  ______________

U.S. Bank Trust National Association
Attention:  Corporate Trust Administration

Ladies and Gentlemen:

     In connection with our proposed sale of certain 8-3/8% Series [A/B] Senior
Subordinated Notes due 2008 (the "Securities") of Ocean Energy, Inc., a Delaware
corporation (the "Company"), we represent that:

          (i) the offer of the Securities was not made to a person in the United
     States;

          (ii) at the time the buy order was originated, the transferee was
     outside the United States or we and any person acting on our behalf
     reasonably believed that the transferee was outside the United States;

          (iii)  no directed selling efforts have been made by us in the United
     States in contravention of the requirements of Rule 903(b) or Rule 904(b)
     of Regulation S under the U.S. Securities Act of 1933, as applicable; and

          (iv) the transaction is not part of a plan or scheme to evade the
     registration requirements of the U.S. Securities Act of 1933.

     You and the Company are entitled to rely upon this letter and you are
irrevocably authorized to produce this letter or a copy hereof to any interested
party in any administrative or legal proceedings or official inquiry with
respect to the matters covered hereby.  Terms used in this certificate have the
meanings set forth in Regulation S under the U.S. Securities Act of 1933.

                              Very truly yours,


                              _____________________________________ 
                              [Name]

                              By:__________________________________
                                    Name:__________________________
                                    Title:_________________________
                                    Address:_______________________

                                      C-1