<PAGE>

                                  EXHIBIT 3.1

                          CERTIFICATE OF INCORPORATION

                                       OF

                           FIRST SEISMIC CORPORATION


                                   ARTICLE I

     The name of the corporation is FIRST SEISMIC Corporation (hereinafter
referred to as the "Corporation").


                                   ARTICLE II

     The address of the registered office of the Corporation in the State of
Delaware is 1209 Orange Street, in the City of Wilmington, County of New
Castle. The name of the registered agent at such address is The Corporation
Trust Company.


                                  ARTICLE III

     The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General
Corporation Law of the State of Delaware.


                                   ARTICLE IV

     Section 1.  AUTHORIZED SHARES.  The number of shares of capital stock of
all classes which the Corporation shall have authority to issue is thirty
million (30,000,000) shares, of which twenty million (20,000,000) shares
shall be of a class designated as Common Stock, with a par value of One Cent
($.01) per share, and ten million (10,000,000) shares shall be of a class
designated as Preferred Stock, with a par value of One Dollar ($1.00).

     Section 2.  DESIGNATIONS, POWERS AND PREFERENCES.  The designations and
the powers, preferences and rights, and the qualifications, limitations or
restrictions of the shares of each class of stock are as follows:

                 A.  PREFERRED STOCK.  Shares of Preferred Stock may be
issued in one or more series at such time or times as the Board of Directors
may determine. All shares of any one series of Preferred Stock shall be of
equal rank and identical in all respects except as to the dates from and
after which dividends thereon shall cumulate, if cumulative. The number of
authorized shares of preferred stock may be increased or decreased by the
affirmative vote of a majority of the stock of the Corporation entitled to
vote without the separate vote of holders of

<PAGE>

Preferred Stock as a class. Subject to the limitations hereof and the
limitation prescribed by law, the Board of Directors is expressly authorized
to fix from time to time, by resolution or resolutions adopted prior to the
issuance of and providing for the establishment and/or issuance of any series
of Preferred Stock, the designation of such series and the powers,
preferences, and rights of such series, and the qualifications, limitations
or restrictions thereof. The authority of the Board of Directors with respect
to each such series shall include, but shall not be limited to, determination
of the following:

                     (i)    The distinctive serial designation and number of
     shares comprising each such series (provided that the aggregate number
     of shares constituting all series of Preferred Stock shall not exceed
     one million (1,000,000), which number may (except where otherwise
     provided by the Board of Directors in creating such series) be increased
     or decreased (but not below the number of shares of such series then
     outstanding) from time to time by action of the Board of Directors;

                     (ii)   The rate of dividends, if any, on the shares of
     that series, whether dividends shall be non-cumulative, cumulative to
     the extent earned or cumulative (and, if cumulative, from which date or
     dates), whether dividends shall be payable in cash, property, or rights,
     or in shares of the Corporation's capital stock, and the relative shares
     of priority, if any, of payment of dividends on shares of that series
     over shares of any other series;

                     (iii)  Whether the shares of that series shall be
     redeemable and, if so, the terms and conditions of such redemption,
     including the date or dates upon or after which they shall be
     redeemable, the event or events upon or after which they shall be
     redeemable or at whose option they shall be redeemable, and the amount
     per share payable in case of redemption (which amount may vary under
     different conditions and at different redemption dates) or the property
     or rights, including securities of any other corporation, payable in
     case of redemption;

                     (iv)   Whether that series shall have sinking fund for
     the redemption or purchase of shares of that series and, if so, the
     terms and amounts payable into such sinking fund;

                     (v)    The rights to which the holders of the shares of
     that series shall be entitled in the event of voluntary or involuntary
     liquidation, dissolution or winding-up of the Corporation, and the
     relative rights of priority, if any, of payment of shares of that series
     in any such event;


                                     -2-
<PAGE>

                     (vi)   Whether the shares of that series shall be
     convertible into or exchangeable for shares of stock of any other class
     or any other series and, if so, the terms and conditions of such
     conversion or exchange, including the rate or rates of conversion or
     exchange, the date or dates upon or after which they shall be
     convertible or exchangeable or at whose option they shall be convertible
     or exchangeable, and the method (if any) of adjusting the rates of
     conversion or exchange in the event of a stock split, stock dividend,
     combination of shares or similar event;

                     (vii)  Whether the issuance of any additional shares of
     such series shall be subject to restrictions, or whether any shares of
     any other series shall be subject to restrictions as to issuance, or as
     to the powers, preferences or rights of any such other series;

                     (viii) Voting rights, if any, including, without
     limitation, the authority to confer multiple votes per share, voting
     rights as to specified matters or issues or, subject to the provisions
     of this Certificate of Incorporation, voting rights to be exercised
     either together with holders of common stock as a single class, or
     independently as a separate class; and

                     (ix)   Any other preferences, privileges and powers and
     relative, participating, optional or other special rights and
     qualifications, limitations or restrictions of such series, as the Board
     of Directors may deem advisable and as shall not be inconsistent with
     the provisions of this Certificate of Incorporation and to the full
     extent now or hereafter permitted by the laws of the State of Delaware.

                 B.  COMMON STOCK.  Subject to all of the rights of the
Preferred Stock, and except as may be provided with respect to the Preferred
Stock herein, by law or by the Board of Directors pursuant to this Article IV:

                     (i)    Dividends may be declared and paid or set apart
     for payment upon the Common Stock out of any assets or funds of the
     Corporation legally available for the payment of dividends.

                     (ii)   The holders of Common Stock shall have the
     exclusive right to vote for the election of directors and on all other
     matters requiring stockholder action, each share being entitled to one
     vote; and

                     (iii)  Upon the voluntary or involuntary liquidation,
     dissolution or winding up of the Corporation, the net assets of the
     Corporation shall be distributed pro rata to the holders of the Common
     Stock in accordance with their respective rights and interests.


                                     -3-
<PAGE>

                 C.  PREEMPTIVE RIGHTS.  No holder of any stock of the
Corporation of any class shall have the preemptive right to subscribe for or
purchase any part of any new or additional issue of stock of any class
whatsoever of the Corporation, or of securities convertible into or
exchangeable for stock of any class whatsoever, whether now or hereafter
authorized, or whether issued for cash or other consideration or by way of
dividend.


                                   ARTICLE V

     For the management of the business and for the conduct of the affairs of
the Corporation, and in further creation, definition, limitation and
regulation of the powers of the Corporation and of its directors and of its
stockholders, it is further provided.

     Section 1.  ELECTIONS OF DIRECTORS.  Elections of Directors need not be
by written ballot unless the By-Laws of the Corporation shall so provide.

     Section 2.  NUMBER, ELECTION, AND TERMS OF DIRECTORS.  Except as
otherwise fixed pursuant to the provisions of Article IV hereof relating to
the rights of the holders of any class or series of stock having a preference
over the Common Stock as to dividends or upon liquidation to elect additional
directors under specified circumstances, the number of directors of the
Corporation shall be fixed from time to time by or pursuant to the By-Laws,
provided, however, that the number of directors shall at no time be less than
three nor greater than nine. The directors, other than those who may be
elected by the holders of any class or series of stock having preference over
the Common Stock as to dividends or upon liquidation, shall be classified,
with respect to the time for which they severally hold office, into three
classes, as nearly equal in number as possible, as shall be provided in the
manner specified in the By-Laws, Class I to hold office initially for a term
expiring at the annual meeting of stockholders to be held during the fiscal
year ending in 1991, Class II to hold office initially for a term expiring at
the annual meeting of stockholders to be held during the fiscal year ending
in 1992, and Class III to hold office initially for a term expiring at the
annual meeting of stockholders to be held during the fiscal year ending in
1993, with the members of each class to hold office until their successors
are elected and qualified. At each annual meeting of the stockholders of the
Corporation, the successors to the class of directors whose term expires at
that meeting shall be elected to hold office for a term expiring at the
annual meeting of stockholders held in the third year following the year of
their election.

     Section 3.  STOCKHOLDER NOMINATION OF DIRECTOR CANDIDATES.  Advance
notice of nominations for the election of


                                     -4-
<PAGE>

directors, other than by the Board of Directors or a Committee thereof, shall
be given in the manner provided in the By-Laws.

     Section 4.  NEWLY CREATED DIRECTORSHIPS AND VACANCIES.  Except as
otherwise fixed pursuant to the provisions of Article IV hereof relating to
the rights of the holders of any class or series of stock having a preference
over the Common Stock as to dividends or upon liquidation to elect directors
under specified circumstances, newly created directorships resulting from any
increase in the number of directors and any vacancies on the Board of
Directors resulting from death, resignation, disqualification, removal or
other cause shall be filled solely by the affirmative vote of a majority of
the remaining Directors then in office, even though less than a quorum of the
Board of Directors. Any director elected in accordance with the preceding
sentence shall hold office for the remainder of the full term of the class of
directors in which the new directorship was created or the vacancy occurred
and until such director's successor shall have been elected and qualified. No
decrease in the number of directors constituting the Board of Directors shall
shorten the term of any incumbent director.

     Section 5.  REMOVAL OF DIRECTORS.  Subject to the rights of any class or
series of stock having preference over the Common Stock as to dividends or
upon liquidation to elect directors under specified circumstances, any
director may be removed from office without cause only by the affirmative
vote of the holders of two-thirds (66.67%) of the combined voting power of
the then outstanding shares of stock entitled to vote generally in the
election of directors, voting together as a single class.

     Section 6.  STOCKHOLDER ACTIONS.  Any action required or permitted to be
taken by the stockholders of the Corporation must be effected at a duly
called annual or special meeting of such stockholders and may not be effected
by any consent in writing by such stockholders. Except as otherwise required
by law and subject to the rights of the holders of any class or series of
stock having a preference over the Common Stock as to dividends or upon
liquidation, special meetings of stockholders of the Corporation may be
called only by the Chairman of the Board, the President or the Board of
Directors pursuant to a resolution approved by a majority of the entire Board
of Directors.

     Section 7.  BY-LAW AMENDMENTS.  The Board of Directors shall have power
to make, alter, amend and repeal the By-Laws (except so far as the By-Laws
adopted by the stockholders shall otherwise provide). Any By-Laws made by the
directors under the powers conferred hereby may be altered, amended or
repealed by the directors or by the stockholders. Notwithstanding the
foregoing and anything contained in this Certificate of Incorporation to the
contrary, Articles II and III of the By-Laws shall not be altered, amended or
repealed and no provision


                                     -5-
<PAGE>

inconsistent therewith shall be adopted without the affirmative vote of the
holders of at least two-thirds (66.67%) of the voting power of all the shares
of the Corporation entitled to vote generally in the election of directors,
voting together as a single class.

     Section 8.  AMENDMENT, REPEAL, ETC.  Notwithstanding anything contained
in this Certificate of Incorporation to the contrary, the affirmative vote of
the holders of at least two thirds (66.67%) of the voting power of all shares
of the Corporation entitled to vote generally in the election of directors,
voting as a single class, shall be required to alter, amend, adopt any
provision inconsistent with, or repeal, this Article V or any provision
hereof.


                                   ARTICLE VI

     Section 1.  VOTE REQUIRED FOR CERTAIN BUSINESS COMBINATIONS.

                 A.  HIGHER VOTE FOR CERTAIN BUSINESS COMBINATIONS.  In
addition to any affirmative vote required by law or this Certificate of
Incorporation, and except as otherwise expressly provided in Section 2 of
this Article VI:

                     (i)    any merger or consolidation of the Corporation or
     any Subsidiary (as hereinafter defined) with (a) any Interested
     Stockholder (as hereinafter defined) or (b) any other corporation
     (whether or not itself an Interested Stockholder) which is, or after
     such merger or consolidation would be, an Affiliate (as hereinafter
     defined) of an Interested Stockholder; and

                     (ii)   any sale, lease, exchange, mortgage, pledge,
     transfer or other disposition (in one transaction or a series of
     transactions) to or with any Interested Stockholder or any Affiliate of
     any Interested Stockholder of any assets of the Corporation having an
     aggregate Fair Market Value of $2,000,000 or more; or

                     (iii)  the issuance or transfer by the Corporation or
     any Subsidiary (in one transaction or a series of transactions) of any
     securities of the Corporation or any Subsidiary to any Interested
     Stockholder or any Affiliate of any Interested Stockholder in exchange
     for cash, securities or other property (or a combination thereof) having
     an aggregate Fair Market Value of $2,000,000 or more; or

                     (iv)   the adoption of any plan or proposal for the
     liquidation or dissolution of the Corporation proposed by or on behalf
     of any Interested Stockholder or any Affiliate of any Interested
     Stockholder; or


                                     -6-
<PAGE>

                     (v)    any reclassification of securities (including any
     reverse stock split), recapitalization, reorganization, merger or
     consolidation of the Corporation, or any other transaction (whether or
     not with or into or otherwise involving an Interested Stockholder) which
     has the effect, directly or indirectly, of increasing the proportionate
     share of the outstanding shares of any class of Equity Security (as
     hereinafter defined) of the Corporation or any Subsidiary which is
     directly or indirectly owned by an Interested Stockholder or any
     Affiliate of any Interested Stockholder,

shall require the affirmative vote of the holders of at least two-thirds
(66.67%) of the voting power of the then outstanding shares of capital stock
of the Corporation entitled to vote generally in the election of directors
(the "Voting Stock"), voting together as a single class (it being understood
that for the purposes of this Article VI, each share of the Voting Stock
shall have the number of votes granted to it pursuant to or in accordance
with the provisions of Article IV of this Certificate of Incorporation). Such
affirmative vote shall be required notwithstanding the fact that no vote may
be required, or that a lesser percentage may be specified, by law or in any
agreement with any national securities exchange or otherwise.

                 B.  DEFINITION OF "BUSINESS COMBINATION."  The term
"Business Combination" used in this Article VI shall mean any transaction
which is referred to in any one or more of clauses (i) through (v) of
Paragraph A of this Section 1.

     Section 2.  WHEN HIGHER VOTE IS NOT REQUIRED.

     The provisions of Section 1 of this Article VI shall not be applicable
to any particular Business Combination, and such Business Combination shall
require only such affirmative vote as is required by law and any other
provision of this Certificate of Incorporation, if all of the conditions
specified in either of the following paragraphs A or B are met:

                 A.  APPROVAL BY DISINTERESTED DIRECTORS.  The Business
Combination shall have been approved by a majority of the Disinterested
Directors (as hereinafter defined).

                 B.  PRICE AND PROCEDURE REQUIREMENTS.  All of the following
conditions shall have been met:

                     (i)    The aggregate amount of the cash and the Fair
     Market Value (as hereinafter defined) as of the date of the consummation
     of the Business Combination of the consideration other than cash to be
     received per share by holders of Common Stock in such Business
     Combination, shall be at least equal to the higher of the following:


                                     -7-
<PAGE>

                            (a)  if applicable, the highest per share price
                 (including any brokerage commissions, transfer taxes and
                 soliciting dealers' fees) paid by the Interested Stockholder
                 for any shares of Common Stock acquired by it (1) within the
                 two-year period immediately prior to the first public
                 announcement of the terms of the proposed Business
                 Combination (the "Announcement Date") or (2) in the
                 transaction in which it became an Interested Stockholder,
                 whichever is higher; or

                            (b)  the Fair Market Value per share of Common
                 Stock on the Announcement Date or on the date on which the
                 Interested Stockholder became an Interested Stockholder
                 (such latter date is referred to in this Article VI as the
                 "Determination Date"), whichever is higher.

                     (ii)   The aggregate amount of the cash and the Fair
     Market Value as of the date of the consummation of the Business
     Combination of consideration other than cash to be received per share by
     holders of shares of any other class of outstanding Voting Stock shall
     be at least equal to the highest of the following (it being intended
     that the requirements of this paragraph B(ii) shall be required to be
     met with respect to every class of outstanding Voting Stock, whether or
     not the Interested Stockholder has previously acquired any shares of a
     particular class of Voting Stock):

                            (a)  if applicable, the highest per share price
                 (including any brokerage commissions, transfer taxes and
                 soliciting dealers' fees) paid by the Interested Stockholder
                 for any shares of such class of Voting Stock acquired by it
                 (1) within the two-year period immediately prior to the
                 Announcement Date or (2) in the transaction in which it
                 became an Interested Stockholder, whichever is higher; or

                            (b)  if applicable, the highest preferential
                 amount per share to which the holders of shares of such
                 class of Voting Stock are entitled in the event of any
                 voluntary or involuntary liquidation, dissolution or winding
                 up of the Corporation); or

                            (c)  the Fair Market Value per share of such
                 class of Voting Stock on the Announcement Date or on the
                 Determination Date, whichever is higher.

                     (iii)  The consideration to be received by holders of a
     particular class of outstanding Voting Stock (including Common Stock)
     shall be in cash or in the same form as the Interested Stockholder has
     previously paid for shares of such class of Voting Stock. If the
     Interested Stockholder has paid for shares of any class of Voting Stock


                                     -8-
<PAGE>

     with varying forms of consideration, the form of consideration for such
     class of Voting Stock shall be either cash or the form used to acquire
     the largest number of shares of such class of Voting Stock previously
     acquired by it. The price determined in accordance with paragraph B(i)
     and B(ii) of this Section 2 shall be subject to appropriate adjustment
     in the event of any stock dividend, stock split, combination of shares
     or similar event.

                     (iv)   After such Interested Stockholder has become an
     Interested Stockholder and prior to the consummation of such Business
     Combination: (a) except as approved by a majority of the Disinterested
     Directors, there shall have been no failure to declare and pay at the
     regular date therefor any full quarterly dividends (whether or not
     cumulative) on any outstanding stock having preference over the Common
     Stock as to dividends or upon liquidation; (b) there shall have been (1)
     no reduction in the annual rate of dividends paid on the Common Stock
     (except as necessary to reflect any subdivision of the Common Stock),
     except as approved by a majority of the Disinterested Directors, and (2)
     an increase in such annual rate of dividends as necessary to reflect any
     reclassification (including any reverse stock split), recapitalization,
     reorganization or any similar transaction which has the effect of
     reducing the number of outstanding shares of the Common Stock, unless
     the failure to so increase such annual rate is approved by a majority of
     the Disinterested Directors; and (c) such Interested Stockholder shall
     have not become the beneficial owner of any additional shares of Voting
     Stock except as part of the transaction which results in such Interested
     Stockholder becoming an Interested Stockholder.

                     (v)    After such Interested Stockholder has become an
     Interested Stockholder, such Interested Stockholder shall not have
     received the benefit, directly or indirectly (except proportionately as
     a stockholder), of any loans, advances, guarantees, pledges or other
     financial assistance or any tax credits or other tax advantages provided
     by the Corporation, whether in anticipation of or in connection with
     such Business Combination or otherwise.

                     (vi)   A proxy or information statement describing the
     proposed Business Combination and complying with the requirements of the
     Securities Exchange Act of 1934, as amended, and the rules and
     regulations thereunder (or any subsequent provisions replacing such Act,
     rules or regulations) shall have been mailed to public stockholders of
     the Corporation at least thirty (30) days prior to the consummation of
     such Business Combination (whether or not such proxy or information
     statement is required to be mailed pursuant to such Act or subsequent
     provisions).


                                     -9-
<PAGE>

     Section 3.  CERTAIN DEFINITIONS.

     For the purposes of this Article VI:

                 A.  A "person" shall mean any individual, firm, corporation
or other entity.

                 B.  "Interested Stockholder" shall mean any person (other
than the Corporation or any Subsidiary) who or which:

                     (i)    is the beneficial owner, directly or indirectly,
     of five percent (5%) or more of the voting power of the outstanding
     Voting Stock; or

                     (ii)   is an Affiliate of the Corporation and at any
     time within the two-year period immediately prior to the date in
     question was in beneficial owner, directly or indirectly, of 5% or more
     of the voting power of the then outstanding Voting Stock; or

                     (iii)  is an assignee of or has otherwise succeeded to
     any shares of Voting Stock which were at any time within the two-year
     period immediately prior to the date in question beneficially owned by
     any Interested Stockholder, if such assignment or succession shall have
     occurred in the course of a transaction or series of transactions not
     involving a public offering within the meaning of the Securities Act of
     1933, as amended.

                 C.  A person shall be "beneficial owner" of any Voting Stock:

                     (i)    which such person of any of its Affiliates or
     Associates (as hereinafter defined) beneficially owns directly or
     indirectly; or

                     (ii)  which such person or any of its Affiliates or
     Associates has (a) the right to acquire (whether such right is
     exercisable immediately or only after the passage of time), pursuant to
     any agreement, arrangement or understanding or upon the exercise of
     conversion rights, exchange rights, warrants or options, or otherwise,
     or (b) the right to vote pursuant to any agreement, arrangement or
     understanding; or

                     (iii)  which are beneficially owned, directly or
     indirectly, by any other person with which such person or any of its
     Affiliates or Associates has any agreement, arrangement or understanding
     for the purpose of acquiring, holding, voting or disposing of any shares
     of Voting Stock.

                 D.  For the purpose of determining whether a person is an
Interested Stockholder pursuant to paragraph B of


                                     -10-
<PAGE>

this Section 3, the number of shares of Voting Stock deemed to be outstanding
shall include shares deemed owned through application of paragraph C of this
Section 3 but shall not include any other shares of Voting Stock which may be
issuable pursuant to any agreement, arrangement or understanding, or upon
exercise of conversion rights, warrants or options, or otherwise.

                 E.  "Affiliate" or "Associate" shall have the respective
meanings ascribed to such terms in Rule 12b-2 of the Rules and Regulations
under the Securities Exchange Act of 1934, as in effect on January 1, 1990.

                 F.  "Subsidiary" means any corporation of which a majority
of any class of Equity Security is owned, directly or indirectly, by the
Corporation, provided, however, that for the purposes of the definition of
Interested Stockholder set forth in paragraph B of this Section 3, the term
"Subsidiary" shall mean only a corporation of which a majority of each class
of Equity Security is owned, directly or indirectly, by the Corporation.

                 G.  "Disinterested Director" means any member of the Board
of Directors who is unaffiliated with the Interested Stockholder and was a
member of the Board of Directors prior to the time that the Interested
Stockholder became an Interested Stockholder, and any successor of a
Disinterested Director who is unaffiliated with the Interested Stockholder
and is recommended to succeed a Disinterested Director by a majority of
Disinterested Directors then on the Board of Directors.

                 H.  "Fair Market Value" means: (i) in the case of stock, the
highest closing sale price during the 30-day period immediately preceding the
date in question of a share of such stock on the Composite Tape for the New
York Stock Exchange -- Listed Stocks, or, if such stock is not quoted on the
Composite Tape, on the New York Stock Exchange, on the principal United
States securities exchange registered under the Securities Exchange Act of
1934 on which such stock is listed, or, if such stock is not listed on any
such exchange, on the National Association of Securities Dealers, Inc.
Automated Quotations System ("NASDAQ") National Market, or, if such stock is
not traded on the NASDAQ National Market, the highest closing bid quotation
with respect to a share of such stock during the 30-day period preceding the
date in question on the NASDAQ or any system then in use, or if no such
quotations are available, the fair market value on the date in question of a
share of such stock as determined by the Board of Directors in good faith;
and (ii) in the case of property other than cash or stock, the fair market
value of such property on the date in question as determined by the Board of
Directors in good faith.

                 I.  In the event of any Business Combination in which the
Corporation survives, the phrase "consideration other than cash to be
received" as used in paragraph B(i) and (ii) of Section 2 of this Article VI
shall include the shares of Common


                                     -11-
<PAGE>

Stock and/or the shares of any other class of outstanding Voting Stock
retained by the holders of such shares.

                 J.  "Equity Security" shall have the meaning ascribed to
such term in Section 3(a)(11) of the Securities Exchange Act of 1934, as in
effect on January 1, 1990.

     Section 4.  POWERS OF THE BOARD OF DIRECTORS.

     A majority of the directors shall have the power and duty to determine
for the purposes of this Article VI, on the basis of information known to
them after reasonable inquiry, (A) whether a person is an Interested
Stockholder, (B) the number of shares of Voting Stock beneficially owned by
any person, (C) whether a person is an Affiliate or Associate of another, (D)
whether the assets which are the subject of any Business Combination have, or
the consideration to be received for the issuance or transfer of securities
by the Corporation or any Subsidiary in any Business Combination has, an
aggregate Fair Market Value of $2,000,000 or more. A majority of the
directors shall have the further power to interpret all of the terms and
provisions of this Article VI.

     Section 5.  NO EFFECT ON FIDUCIARY OBLIGATIONS OF INTERESTED
STOCKHOLDERS.

     Nothing contained in this Article VI shall be construed to relieve any
Interested Stockholder from any fiduciary obligation imposed by law.

     Section 6.  AMENDMENT, REPEAL, ETC.

     Notwithstanding any other provisions of this Certificate of
Incorporation or the By-Laws (and notwithstanding the fact that a lesser
percentage may be specified by law, this Certificate of Incorporation or the
By-Laws) the affirmative vote of the holders of two-thirds (66.67%) or more
of the outstanding Voting Stock, voting together as a single class, shall be
required to amend or repeal, or adopt any provision inconsistent with this
Article VI or any provision hereof.


                                  ARTICLE VII

     No director shall be personally liable to the Corporation or any
stockholder for monetary damages for breach of fiduciary duty as a director,
except (i) for any breach of such director's duty of loyalty to the
Corporation or its stockholders, (ii) for acts or omissions not in good faith
or which involve intentional misconduct or knowing violation of law, (iii)
under Section 174 of the Delaware General Corporation Law, or (iv) for any
transaction from which the director derived an improper personal benefit. If
the Delaware General Corporation Law is amended after approval by the
stockholders of this


                                     -12-
<PAGE>

provision to authorize corporate action further eliminating or limiting the
personal liability of directors, then the liability of directors of the
Corporation shall be eliminated or limited to the full extent permitted by
the Delaware General Corporation Law, as so amended.


                                  ARTICLE VIII

     The Corporation shall indemnify to the full extent permitted by the laws
of the State of Delaware as from time to time in effect any person who was or
is a party or is threatened to be made a party to, or otherwise requires
representation by counsel in connection with, any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative
or investigative (whether or not an action by or in the right of the
Corporation), by reason of the fact that he is or was a director or officer
of the Corporation, or, while serving as a director or officer of the
Corporation, is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation, partnership,
joint venture, trust or other enterprise, or by reason of any action alleged
to have been taken or omitted in such capacity. The right to indemnification
conferred by this Article IX shall also include the right of such persons to
be paid in advance by the Corporation for their expenses to the full extent
permitted by the laws of the State of Delaware as from time to time in
effect. The right to indemnification conferred on such persons by this
Article IX shall be a contract right.

     Unless otherwise determined by the Board of Directors of the
Corporation, the Corporation shall indemnify to the full extent permitted by
the laws of the State of Delaware as from time to time in effect any person
who was or is a party or is threatened to be made a party to, or otherwise
requires representation by counsel in connection with, any threatened,
pending or completed action, suit or proceeding, whether civil, criminal,
administrative or investigative (whether or not an action by or in the right
of the Corporation), by reason of the fact that he is or was an employee
(other than an officer) or agent of the Corporation, or is or was serving as
a director, officer, employee or agent of another corporation, partnership,
joint venture, trust or other enterprise, or by reason of any action alleged
to have been taken or omitted in such capacity.

     The rights and authority conferred in this Article IX shall not be
exclusive of any other right which any person may have or hereafter acquire
under any statute, provision of this Certificate of Incorporation or By-Laws
of the Corporation, agreement, vote of stockholders or Disinterested
Directors or otherwise.

     Neither the amendment nor repeal of this Article IX, nor the adoption of
any provision of the Certificate of


                                     -13-
<PAGE>

Incorporation or By-Laws or of any statute inconsistent with this Article IX,
shall eliminate or reduce the effect of this Article IX, in respect of any
acts or omissions occurring prior to such amendment, repeal or adoption of an
inconsistent provision.


                                   ARTICLE IX

     The names and mailing addresses of the persons who shall serve as the
initial directors of the Corporation, and, pursuant to Article V, Section 2,
the Classes to which they are assigned, are as follows:


                                    CLASS I

                                 Marvin Hewitt
              5916 So. Indianapolis Ave., Tulsa, Oklahoma 74135


                                   CLASS II

                                 Warren DeMoss
                     1007 Tulip Tree, Houston, Texas 77090


                                  CLASS III

                                Rogers E. Beall
              9400 East Maplewood Ave., Englewood, Colorado 80111

Each such director shall serve for the term specified in Article V, Section
2, for his respective Class and until his successor is elected and qualified.


                                   ARTICLE X

     The Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Certificate of Incorporation, in the manner now
or hereafter prescribed by statute and this Certificate of Incorporation, and
all rights conferred upon stockholders herein are granted subject to this
reservation.


                                   ARTICLE XI

     The name and mailing address of the sole incorporator is: David A.
Dilger, 370 17th Street, Suite 4700, Denver, Colorado 80202. The powers of
the incorporator shall terminate upon the filing of this Certificate of
Incorporation in the office of the Secretary of State of the State of Delaware.

     The undersigned, being the sole incorporator herein before named, for
the purpose of forming a corporation pursuant to the General Corporation Law
of the State of Delaware, does make this Certificate of Incorporation, hereby
declaring,


                                     -14-
<PAGE>

affirming, acknowledging and certifying, under penalties of perjury, that
this is the act and deed of the undersigned and that the facts stated herein
are true, and accordingly has hereunto set his hand this 7 day of June, 1990.


                                            SOLE INCORPORATOR

                                            /s/ David A. Dilger
                                            ------------------------------


                                     -15-
<PAGE>

                                                                 PAGE 1

                              STATE OF DELAWARE

                                    [LOGO]

                         OFFICE OF SECRETARY OF STATE


     I, MICHAEL HARKINS, SECRETARY OF STATE OF THE STATE OF DELAWARE DO
HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
AMENDMENT OF FIRST SEISMIC CORPORATION FILED IN THIS OFFICE ON THE
SEVENTEENTH DAY OF SEPTEMBER, A.D. 1990, AT 10:30 O'CLOCK A.M.


                    *  *  *  *  *  *  *  *  *  *  *  *



                                       /s/ Michael Harkins
                                       -----------------------------------
                                       Michael Harkins, Secretary of State

       [SEAL]                          AUTHENTICATION:  *3835647
                 911215111                       DATE:  05/01/1991

<PAGE>

                                                          STATE OF DELAWARE
                                                         SECRETARY OF STATE
                                                      DIVISION OF CORPORATIONS
                                                     FILED 10:30 AM 09/17/1990
                                                        730260047 - 2232755

                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                           FIRST SEISMIC CORPORATION


     FIRST SEISMIC Corporation, a corporation organized and existing under
and by virtue of the General Corporation Law of the State of Delaware,

     DOES HEREBY CERTIFY:

     FIRST:  That at a meeting of the Board of Directors of FIRST SEISMIC
Corporation, resolutions were duly adopted setting forth the proposed
amendments of the Certificate of Incorporation of said corporation, declaring
said amendment to be advisable and calling a meeting of the stockholders of
said corporation for consideration thereof. The resolution setting forth the
proposed amendments are as follows:

     RESOLVED, that the Certificate of Incorporation of this corporation be
     amended by changing Article V, Section 4 and Section 6 so that, as
     amended said Article shall be and read as follows:

                 Section 4.  NEWLY CREATED DIRECTORSHIPS AND VACANCIES.
                 Except as otherwise fixed pursuant to the provisions of
                 Article IV hereof relating to the rights of the holders of
                 any class or series of stock having a preference over the
                 Common Stock as to dividends or upon liquidation to elect
                 directors under specified circumstances, newly created
                 directorships resulting from any increase in the number of
                 directors and any vacancies on the Board of Directors
                 resulting from death, resignation, disqualification, removal
                 or other cause shall be filled solely by the affirmative
                 vote of a majority of the remaining Directors then in
                 office, even though less than a quorum of the Board of
                 Directors; provided that any vacancy created by a removal of
                 a director of the Corporation pursuant to Section 5 of this
                 Article V may be filled by action of the stockholders taken
                 at the same meeting at which the vacancy was created. Any
                 director elected in accordance with the preceding sentence
                 shall hold office for the remainder of the full term of
                 the class of directors in which the new directorship was
                 created or the vacancy occurred and until such director's
                 successor shall have been elected and qualified. No decrease
                 in the number of directors

<PAGE>

                 constituting the Board of Directors shall shorten the term
                 of any incumbant director.

                 Section 6.  STOCKHOLDER ACTIONS.  Any action required or
                 permitted to be taken by the stockholders of the Corporation
                 must be effected at a duly called annual or special meeting
                 of such stockholders and may not be effected by any consent
                 in writing by such stockholders. Except as otherwise
                 required by law and subject to the rights of the holders of
                 any class or series of stock having a preference over the
                 Common Stock as to dividends or upon liquidation, special
                 meetings of stockholders of the Corporation may be called
                 only by the Chairman of the Board, the President or the Board
                 of Directors pursuant to a resolution approved by a majority
                 of the entire Board of Directors, and shall be called by the
                 President or Secretary at the written request of
                 stockholders holding at least 10% of the outstanding capital
                 stock of the Corporation issued and outstanding and entitled
                 to vote. Such request shall state the purpose or purposes of
                 the proposed meeting.

     SECOND:  That thereafter, pursuant to resolution of its Board of
Directors, a special meeting of the stockholders of said corporation was duly
called and held, upon notice in accordance with the General Corporation Law
of the State of Delaware at which meeting the necessary number of shares were
voted in favor of the amendment.

     THIRD:  That said amendment was duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.

     FOURTH:  That the capital of said corporation shall not be reduced under
or by reason of said amendment.

     IN WITNESS WHEREOF, FIRST SEISMIC Corporation has caused this
certificate to be signed by Rogers E. Beall, its President, and Eric A.
Simons, its Secretary, this 15 day of September, 1990.

                                  By:  /s/ Rogers E. Beall
                                       -----------------------------------
                                  President



                                  Attest:  /s/ Eric A. Simons
                                           -------------------------------
                                  Secretary


                                      -2-
<PAGE>

                                                        STATE OF DELAWARE
                                                        SECRETARY OF STATE
                                                     DIVISION OF CORPORATIONS
                                                     FILED 09:00 AM 07/23/1992
                                                        922065067 - 2232755

CERTIFICATE OF AMENDMENT OF
CERTIFICATE OF INCORPORATION

FIRST SEISMIC Corporation, a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware,

DOES HEREBY CERTIFY:

FIRST:  That at a meeting of the Board of Directors of FIRST SEISMIC
Corporation resolutions were duly adopted setting forth a proposed amendment
of the Certificate of Incorporation of said corporation, declaring said
amendment to be advisable and calling a meeting of the stockholders of said
corporation for consideration thereof. The resolutions setting forth the
proposed amendment is as follows:

     RESOLVED, that the Certificate of Incorporation of this corporation be
amended by changing the Article thereof numbered "Article IV" so that, as
amended, said Article shall be and read as follows:

     Section 1. AUTHORIZED SHARES.  The number of shares of capital stock of
     all classes which the Corporation shall have authority to issue is
     eleven million (11,000,000) shares, of which ten million (10,000,000)
     shares shall be of a class designed as Common Stock, with a par value of
     One Cent ($.01) per share, and one million (1,000,000) shares shall be
     of a class designed as Preferred Stock, with a par value of One Dollar
     ($1.00).

SECOND:  That thereafter, pursuant to resolution of its Board of Directors,
an annual meeting of the stockholders of said corporation was duly called and
held on June 18, 1992, upon notice in accordance with Section 222 of the
General Corporation Law of the State of Delaware at which meeting the
necessary number of shares as required by statute were voted in favor of the
amendment.

THIRD:  That said amendment was duly adopted in accordance with the provision
of Section 242 of the General Corporation Law of the State of Delaware.

FOURTH:  That the capital of said corporation shall not be reduced under or
by reason of said amendment.

IN WITNESS WHEREOF, said FIRST SEISMIC Corporation has caused this
certificate to be signed by Rogers E. Beall, its President, and James Wilson,
its Secretary this 14th day of July, 1992.

                                  By:  /s/ Rogers E. Beall
                                       -----------------------------------
                                               President



                                  By:  /s/ James Wilson
                                            ------------------------------
                                               Secretary