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                                                                  EXHIBIT 10.3.1


                            FIRST AMENDMENT TO THE
                  AMENDED AND RESTATED STOCKHOLDERS AGREEMENT

     THIS FIRST AMENDMENT TO THE AMENDED AND RESTATED STOCKHOLDERS AGREEMENT
(this "Amendment") is entered into as of July 19, 2000 among Spinnaker
Exploration Company, a Delaware corporation (the "Corporation"), Warburg, Pincus
Ventures, L.P., ("WPV"), Seismic Energy Holdings, Inc., a Delaware corporation
("SESI"), Roger L. Jarvis and James M. Alexander.

                                  WITNESSETH:

     WHEREAS, WPV, SESI, Roger L. Jarvis and James M. Alexander (collectively,
the "Parties" and each a "Party") together constitute the "Required Holders" as
such term is defined in Section 1.1 of the Amended and Restated Stockholders
Agreement dated as of September 27, 1999 (the "Stockholders Agreement").

     WHEREAS, pursuant to Section 5.1 of the Stockholders Agreement, the Parties
desire to amend the Stockholders Agreement as set forth in this Amendment.

     NOW, THEREFORE, in consideration of the mutual covenants and obligations
hereinafter set forth, the parties hereto, intending to be legally bound, hereby
agree as follows:


                                   ARTICLE I
                                 DEFINED TERMS

     Section 1.1  DEFINED TERMS.  Except as otherwise provided herein,
capitalized terms used in this Amendment shall have the meanings ascribed to
them in the Stockholders Agreement.


                                  ARTICLE II
                                   AMENDMENT


     SECTION 2.1  AMENDMENT.  Section 3 of Exhibit A to the Stockholders
Agreement is hereby amended by adding the following provision immediately after
clause b of Section 3:

     "c.  Notwithstanding the foregoing contained in this Section 3, none of the
          Holders of Registrable Securities shall have any rights pursuant to
          this Section 3 with respect to the registration statement of the
          Corporation filed on July 18, 2000 or any amendments or supplements
          thereto (the "Registration Statement") provided that any offering of
          securities contemplated by such Registration

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          Statement shall have been consummated on or before October 31, 2000."


                                  ARTICLE III
                                 MISCELLANEOUS

     SECTION 3.1  EXTENT OF AMENDMENTS AND REFERENCES.  Except as otherwise
expressly provided herein, the terms and conditions of the Stockholders
Agreement (or any attachments or schedules thereto) shall not be amended,
modified or affected by this Amendment and shall remain in full force and
effect.

     SECTION 3.2  COUNTERPARTS.  This Amendment may be executed in any number of
counterparts, each of which when so executed shall be deemed an original but all
of which together shall constitute one and the same instrument.

                                     SPINNAKER EXPLORATION COMPANY


                                     By: /s/ ROGER L. JARVIS
                                         --------------------
                                         Roger L. Jarvis
                                         President

                                     WARBURG, PINCUS VENTURES, L.P.
                                     By:  Warburg Pincus & Co., Inc.,
                                              its general partner


                                     By: /s/ JEFFREY A. HARRIS
                                         ----------------------
                                         Jeffrey A. Harris
                                         Managing Director

                                     SEISMIC ENERGY HOLDINGS, INC.


                                     By: /s/ SEAN M. GORE
                                         ----------------------
                                     Name: Sean M. Gore
                                     Title: V. P. Finance


                                         /s/ ROGER L. JARVIS
                                     --------------------------
                                     Roger L. Jarvis


                                         /s/ JAMES M. ALEXANDER
                                     --------------------------
                                     James M. Alexander

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