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                    AMENDMENT NO. 2 TO CREDIT AGREEMENT


     THIS AMENDMENT NO. 2 TO CREDIT AGREEMENT (this "AMENDMENT NO. 2"), dated
as of February 23, 2001, between ESENJAY EXPLORATION, INC., a Delaware
corporation (the "BORROWER"), and DEUTSCHE BANK AG, New York and/or Cayman
Islands Branch (the "LENDER"),

                            W I T N E S S E T H:

     WHEREAS, the Borrower and the Lender are parties to that certain Credit
Agreement, dated as of January 25, 2000 (as the same has been from
time-to-time amended, hereinafter referred to as the "EXISTING CREDIT
AGREEMENT"); and

     WHEREAS, the Borrower has requested that certain amendments be made to
the Existing Credit Agreement; and

     WHEREAS, the Lender is willing to make certain amendments to the
Existing Credit Agreement on the terms and conditions hereinafter provided;
and

     NOW, THEREFORE, in consideration of the agreements herein contained, the
parties hereto hereby agree as follows:

                                 ARTICLE I.

                                DEFINITIONS

     SECTION 1.1 CERTAIN DEFINITIONS. The following terms (whether or not
underscored) when used in this Amendment No. 2 shall have the following
meanings:

     "AMENDED CREDIT AGREEMENT" means the Existing Credit Agreement as
amended by this Amendment No. 2.

     SECTION 1.2 OTHER DEFINITIONS. Unless otherwise defined or the context
otherwise requires, terms used herein (including in the preamble and recitals
hereto) have the meanings provided for in the Existing Credit Agreement.

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                                   ARTICLE II.

                                  AMENDMENT TO
                            EXISTING CREDIT AGREEMENT

     Effective as of February 23, 2001, the Existing Credit Agreement is
amended in accordance with the terms of this ARTICLE II; except as so
amended, the Existing Credit Agreement shall continue to remain in all
respects in full force and effect.

     SECTION 2.1 AMENDMENT TO SECTION 1.1.

     (a) SECTION 1.1 is hereby amended by deleting the text of the existing
definition of "Tranche A Availability Termination Date" and inserting the
following definition in its place in SECTION 1.1:

     "TRANCHE A AVAILABILITY TERMINATION DATE" means January 25, 2002.


                                   ARTICLE III.

                          REPRESENTATIONS AND WARRANTIES

     In order to induce the Lender to make the amendments provided for in
ARTICLE II, the Borrower hereby

          (a) represents and warrants that the Borrower has full power and
    authority to execute, deliver and perform its obligations under this
    Amendment No. 2 and all other Loan Documents delivered to Lender in
    connection herewith, and this Amendment No. 2 and all such Loan Documents
    are the legally valid and binding obligations of Borrower, enforceable
    against Borrower in accordance with their respective terms;

          (b) represents and warrants that each of the representations and
    warranties contained in the Existing Credit Agreement and in the other
    Loan Documents is true and correct as of the date hereof as if made on
    the date hereof (except, if any such representation and warranty relates
    to an earlier date, such representation and warranty shall be true and
    correct in all material respects as of such earlier date) and Borrower
    has performed each of the covenants and agreements in the Existing
    Credit Agreement and the other Loan Documents required to be performed
    by Borrower as of the date hereof;

          (c) represents and warrants that there is no Default or Event of
    Default by Borrower or any other Obligor under the Existing Credit
    Agreement or any other Loan Document and no event exists which, with
    the giving of notice or the passage


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     of time or both, would give rise to a Default or Event of Default by
     Borrower or any other Obligor under the Existing Credit Agreement or
     any Loan Document.

                                    ARTICLE IV.

                             CONDITIONS TO EFFECTIVENESS

     SECTION 4.1 EFFECTIVENESS. This Amendment No. 2 shall become effective
when the conditions set forth in this SECTION 4.1 have been satisfied:

          (a) EXECUTION OF COUNTERPARTS. The Lender shall have received
     counterparts of this Amendment No. 2 duly executed and delivered on
     behalf of the Borrower and the Lender.

          (b) CLOSING FEES, EXPENSES, ETC. The Lender shall have received
     all reasonable costs and expenses due and payable pursuant to
     SECTIONS 3.3 and 10.3 of the Existing Credit Agreement, if then invoiced.

          (c) LEGAL DETAILS, ETC. All documents executed or submitted
     pursuant hereto, and all legal matters incident thereto, shall be
     satisfactory in form and substance to the Lender and its counsel.


                                       ARTICLE V.

                                     MISCELLANEOUS

     SECTION 5.1 LOAN DOCUMENT PURSUANT TO EXISTING CREDIT AGREEMENT. This
Amendment No. 2 is a Loan Document executed pursuant to the Existing Credit
Agreement. Except as expressly amended or waived hereby, all of the
representations, warranties, terms, covenants and conditions contained in the
Existing Credit Agreement and each other Loan Document shall remain unamended
and in full force and effect. The amendments set forth herein shall be
limited precisely as provided for herein and shall not be deemed to be a
waiver of, amendment of, consent to or modification of any other term or
provision of the Existing Credit Agreement or of any term or provision of any
other Loan Document or of any transaction or further or future action on the
part of the Borrower which would require the consent of the Lender under the
Existing Credit Agreement or any other Loan Document.

     SECTION 5.2 COUNTERPARTS, ETC. This Amendment No. 2 may be executed by
the parties hereto in several counterparts, each of which shall be deemed to
be an original and all of which shall constitute together but one and the
same agreement with the same effect as if all parties hereto had signed the
same signature page. Any signature

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page of this Amendment No. 2 may be detached from any identical counterpart
of this Amendment No. 2 having attached to it one or more additional
signature pages.

     SECTION 5.3 GOVERNING LAW; ENTIRE AGREEMENT. THIS AMENDMENT NO. 2 SHALL
BE DEEMED TO BE A CONTRACT MADE UNDER AND GOVERNED BY THE INTERNAL LAWS OF
THE STATE OF NEW YORK.

     SECTION 5.4 TITLES AND HEADINGS. The titles and headings of the Sections
of this Amendment No. 2 are intended for convenience only and shall not in
any way affect the meaning or construction of any provision of this Amendment
No. 2.

     SECTION 5.5 CHANGES AND MODIFICATIONS IN WRITING. No provision of this
Amendment No. 2 may be changed or modified except by an instrument in writing
signed by the party against whom enforcement of the change or modification is
sought.

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 2
to be executed by their respective officers hereunto duly authorized as of
the day and year first above written.

                                         BORROWER
                                         --------

                                         ESENJAY EXPLORATION, INC., a
                                         Delaware corporation


                                         By:    /s/ David B. Christofferson
                                                ------------------------------
                                         Name:  David B. Christofferson
                                         Title: Senior Vice President


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                                         LENDER

                                         DEUTSCHE BANK AG, NEW YORK AND/OR
                                         CAYMAN ISLANDS BRANCH




                                         By:    /s/ Gregory J. Moroney
                                                ------------------------------
                                         Name:  Gregory J. Moroney
                                         Title: Managing Director



                                         By:    /s/ John H. Honier
                                                ------------------------------
                                         Name:  John H. Honier
                                         Title: Managing Director