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                                                                     Exhibit 4.8

                              DECLARATION OF TRUST
                              --------------------

         DECLARATION OF TRUST, dated as of October 23, 2001, among Spinnaker
Exploration Company, a Delaware corporation, as sponsor (the "Sponsor"), Mark
Ferrucci as Delaware trustee (the "Delaware Trustee"), and Robert M. Snell and
Jeffrey C. Zaruba, as administrative trustees (the "Administrative Trustees" and
collectively with the Delaware Trustee, the "Trustees"). The Sponsor and the
Trustees hereby agree as follows:

         1. The trust created hereby (the "Trust") shall be known as "Spinnaker
Exploration Finance Trust I", in which name the Trustees, or the Sponsor to the
extent provided herein, may conduct the business of the Trust, make and execute
contracts, and sue and be sued.

         2. The Sponsor hereby assigns, transfers, conveys and sets over to the
Trust the sum of $10. The Trustees hereby acknowledge receipt of such amount
from the Sponsor, which amount shall constitute the initial trust estate. The
Trustees hereby declare that they will hold the trust estate for the Sponsor. It
is the intention of the parties hereto that the Trust created hereby constitute
a business trust under Chapter 38 of Title 12 of the Delaware Code, 12 Del. C.
(SS) 3801 et seq. (the "Business Trust Act"), and that this document constitute
the governing instrument of the Trust. The Trustees are hereby authorized and
directed to execute and file a certificate of trust in the office of the
Secretary of State of the State of Delaware. The Trust is hereby established by
the Sponsor and the Trustees for the purposes of (i) issuing preferred
securities ("Preferred Securities") representing undivided beneficial interests
in the assets of the Trust in exchange for cash and investing the proceeds
thereof in debt securities of the Sponsor, (ii) issuing and selling common
securities ("Common Securities") representing undivided beneficial interests in
the assets of the Trust to the Sponsor in exchange for cash and investing the
proceeds thereof in additional debt securities of the Sponsor and (iii) engaging
in such other activities as are necessary, convenient or incidental thereto.

         3. The Sponsor and the Trustees will enter into an amended and restated
Declaration of Trust, satisfactory to each such party, to provide for the
contemplated operation of the Trust created hereby and the issuance of the
Preferred Securities and the Common Securities referred to therein. Prior to the
execution and delivery of such amended and restated Declaration of Trust, the
Trustees shall not have any duty or obligation hereunder or with respect to the
trust estate, except as otherwise required by applicable law or as may be
necessary to obtain, prior to such execution and delivery, any licenses,
consents or approvals required by applicable law or otherwise.

         4. The Sponsor, as the sponsor of the Trust, are hereby authorized (i)
to prepare and file a Registration Statement (including the Prospectus included
therein and any Prospectus Supplement relating thereto) relating to the
Preferred Securities meeting the requirements of the Securities Act of 1933, as
amended (the "1933 Act"), and such other forms or filings as may be required by
the 1933 Act, the Securities Exchange Act of 1934, as amended, or the Trust
Indenture Act of 1939, as amended, in each case relating to the Preferred
Securities of the Trust; (ii) to file and execute on behalf of the Trust, such
applications, reports, surety bonds, irrevocable consents, appointments of
attorney for service of process and other papers and documents that shall be
necessary or desirable to register or establish the exemption from registration
of the Preferred Securities of the Trust under the securities or "Blue Sky" laws
of

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such jurisdictions as the Sponsor, on behalf of the Trust, may deem necessary or
desirable; (iii) to execute and file an application, and all other applications,
statements, certificates, agreements and other instruments that shall be
necessary or desirable, to the New York Stock Exchange or any other national
stock exchange or the Nasdaq National Market for listing or quotation of the
Preferred Securities of the Trust; (iv) to execute and deliver letters or
documents to, or instruments for filing with, a depository relating to the
Preferred Securities of the Trust; and (v) to execute, deliver and perform on
behalf of the Trust one or more underwriting agreements, purchase agreements,
dealer manager agreements, escrow agreements and other related agreements
providing for or relating to the sale of the Preferred Securities of the Trust.
It is hereby acknowledged and agreed that in connection with any execution,
filing or document referred to in clauses (i)-(iii) above, (A) any
Administrative Trustee (or his attorneys-in-fact and agents or the Sponsor as
permitted herein) is authorized on behalf of the Trust to file and execute such
document on behalf of the Trust and (B) the Delaware Trustee shall not be
required to join in any such filing or execute on behalf of the Trust any such
document unless required by the rules and regulations of the New York Stock
Exchange or any other national stock exchange or the Nasdaq National Market or
state securities or blue sky laws, and in such case only to the extent so
required.

         5. This Declaration of Trust may be executed in one or more
counterparts.

         6. The number of Trustees initially shall be three (3) and thereafter
the number of Trustees shall be such number as shall be fixed from time to time
by a written instrument signed by the Sponsor which may increase or decrease the
number of Trustees; provided, however, that the number of Trustees shall in no
event be less than three (3); and provided, further, however, that to the extent
required by the Business Trust Act, one Trustee shall either be a natural person
who is a resident of the State of Delaware or, if not a natural person, an
entity that has its principal place of business in the State of Delaware and
meets any other requirements imposed by applicable law. Subject to the
foregoing, the Sponsor is entitled to appoint or remove without cause any
Trustee at any time. Any Trustee may resign upon 30 days prior notice to the
Sponsor; provided, however, that the Delaware Trustee may resign immediately
upon notice to the Sponsor if the Delaware Trustee is required to join in any
filing or execute on behalf of the Trust any document pursuant to the provisions
of paragraph 4 hereof and, upon giving such notice, the Delaware Trustee shall
not be required to join in any such filing or execute on behalf of the Trust any
such document; provided, further, however, that no resignation of the Delaware
Trustee shall be effective until a successor Delaware Trustee has been appointed
and has accepted such appointment by instrument executed by such successor
Delaware Trustee and delivered to the Trust, the Sponsor and the resigning
Delaware Trustee.

         7. To the fullest extent permitted by applicable law, the Sponsor
agrees to indemnify (i) the Delaware Trustee, (ii) any affiliate of the Delaware
Trustee, and (iii) any officers, directors, shareholders, members, partners,
employees, representatives, nominees, custodians or agents of the Delaware
Trustee (each of the persons or entities in (i) through (iii) being referred to
as an "Indemnified Person") for, and to hold each Indemnified Person 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 the trust or trusts hereunder, including the costs and
expenses (including reasonable legal fees and expenses) of defending itself
against, or investigating, any claim or liability in connection with the
exercise or

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performance of any of its powers or duties hereunder. The Delaware Trustee shall
not have any of the powers or duties of the trustees set forth herein, except as
required under the Business Trust Act. The Delaware Trustee shall be a trustee
hereunder for the sole and limited purpose of fulfilling the requirements of
Section 3807(a) of the Business Trust Act.

         8.  The Trust may dissolve and terminate without issuing any Trust
Securities at the election of the Sponsor.

         9.  This Declaration shall be governed by the laws of the State of
Delaware, without regard to conflict of laws principles.

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         IN WITNESS WHEREOF, the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.

                          SPINNAKER EXPLORATION COMPANY
                          as Sponsor


                          By: /s/ ROBERT M. SNELL
                             --------------------------------------------------
                              Name:  Robert M. Snell
                              Title: Vice President, Chief Financial Officer
                                     and Secretary



                          By: /s/ MARK A. FERRUCCI
                             --------------------------------------------------
                              Mark A. Ferrucci, as Delaware Trustee


                              /s/ ROBERT M. SNELL
                             --------------------------------------------------
                              Robert M. Snell, as Trustee


                              /s/ JEFFREY C. ZARUBA
                             --------------------------------------------------
                              Jeffrey C. Zaruba, as Trustee

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