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                                                                   Exhibit 10.25



                                  THIRD AMENDMENT OF
                        AMENDED AND RESTATED CREDIT AGREEMENT


     THIS THIRD AMENDMENT OF AMENDED AND RESTATED CREDIT AGREEMENT (this
"Amendment"), dated as of April 30, 1998, is by and among BASIN EXPLORATION,
INC., a Delaware corporation ("Borrower"), U.S. BANK NATIONAL ASSOCIATION f/k/a
COLORADO NATIONAL BANK ("USB"), UNION BANK OF CALIFORNIA, N.A. ("Union"), and
NATIONSBANK OF TEXAS, N.A. ("NBT"), in its capacity as a Lender and as Agent for
Lenders.  USB, Union and NBT are herein collectively referred to as "Lenders."

                                      RECITALS

     A.   Borrower and Lenders entered into an Amended and Restated Credit
Agreement dated as of August 6, 1996 (the "Original Credit Agreement"), as
amended by a First Amendment of Amended and restated credit Agreement dated as
of June 11, 1997 and a Second Amendment of Amended and Restated Credit Agreement
dated as of November 1, 1997, in order to set forth the terms upon which Lenders
would make loans to Borrower and issue letters of credit at the request of
Borrower and by which such loans and letters of credit would be governed.
Capitalized terms used herein without definition shall have the same meanings as
set forth in the Original Credit Agreement, as amended as set forth above (the
"Credit Agreement").

     B.   The parties hereto wish to enter into this Amendment in order to amend
certain terms and provisions of the Credit Agreement.

                                     AGREEMENT

     NOW, THEREFORE, in consideration of $10.00 and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereby agree as follows:

          1.   Credit Agreement.  effective as of the date of this Amendment,
the Credit Agreement shall be, and hereby is, amended as follows:

               (a)  The definition of "Borrowing Base" in Section 1.1 on page 3
of the Credit Agreement shall be deleted, and the following shall be substituted
therefor:


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               "BORROWING BASE" means, at any time, the aggregate loan value of
the Borrowing Bas Properties, as determined by Lenders in accordance with the
provisions of Section 3.2 below; provided that the Borrowing Base for the time
period from April 30, 1998 through the date as of which the November, 1998
redetermination of the Borrowing base pursuant to Section 3.2. below becomes
effective shall be $75,000,000, unless Borrower and Lenders hereafter mutually
agree upon a different amount or unless the Borrowing Base is redetermined
pursuant to Section 3.2 below prior to such date.

               (b)  The definition of "Revolving Period" in Section 1.1 on page
12 of the Credit Agreement shall be deleted, and the following shall be
substituted therefore:

               (c)  "REVOLVING PERIOD" means the time period from the date of
this Agreement through October 31, 2001; provided that, upon the request of
Borrower, Lenders may, in their sole discretion, extend such time period at any
time and from time to time to a date not later than July 31, 2002.

               (d)  The last sentence of Section 2.8 on page 17 of the Credit
Agreement shall be revised to read as follows:  "Borrower shall have no more
than eight Fixed Rate Portions in effect at any time."

               (e)  In Section 3.2 on page 21 of the Credit Agreement:  (1)
"April 15" shall be changed to "May 1" in line 2; (2) "October 15" shall be
changed to "November 1" in line 2; and (3) "April, 1997' shall be changed to
"November, 1998' in line 3.

               (f)  In Section 6.1(b)(v) on pages 32 and 33 of the Credit
Agreement:  (1) "March 1" shall be changed to "March 15" in line 1 on page 32;
and (2) "September 1" shall be changed to "September 15" in the seventh line of
the carryover portion on page 33.

          2.   Loan Documents.  All references in any document to the Credit
Agreement shall refer to the Credit Agreement, as amended and supplemented
pursuant to this Amendment.

          3.   CONDITIONS PRECEDENT.  The obligations of the parties under this
Amendment are subject, at the option of Lenders, to the prior satisfaction of
the condition that Borrower shall have executed and/or delivered, or caused to
have been executed and/or delivered, to or for the benefit of Lenders, the
following (all documents to be satisfactory in form and substance to Lenders):


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          (a)  This Amendment.

          (b)  Such certificates of officers of Borrower as may be required by
               Lenders.

          (c)  Any and all other Loan Documents required by Lenders.

     4.   REPRESENTATIONS AND WARRANTIES.  Borrower hereby certifies to Lenders
that as of the date of (and after giving effect to) this Amendment, except as
heretofore disclosed to and waived by Lenders:  (a) all of Borrower's
representations and warranties contained in the Credit Agreement are true,
accurate and complete in all material respects, and (b) no Default or Event of
Default has occurred and is continuing under the Credit Agreement.

     5.   CONTINUATION OF THE CREDIT AGREEMENT.  Except as specified in this
Amendment, the provisions of the Credit Agreement shall remain in full force and
effect, and if there is a conflict between the terms of this Amendment and those
of the Credit Agreement, the terms of this Amendment shall control.  Borrower
hereby ratifies, confirms and adopts the Credit Agreement, as amended hereby.

     6.   EXPENSES.  Borrower shall pay all reasonable expenses incurred in
connection with the transactions contemplated by this Amendment, including
without limitation all reasonable fees and reasonable expenses of Lenders'
attorneys and all recording and filing fees, charges and expenses.

     7.   MISCELLANEOUS.  This Amendment shall be governed by and construed
under the laws of the State of Colorado and shall be binding upon and inure to
the benefit of the parties hereto and their successors and assigns.  This
Amendment may be executed in any number of counterparts, each of which shall be
an original, but all of which together shall constitute one instrument.
Delivery of this Amendment and any and all documents to be delivered in
connections herewith by any party may be effected, without limitation, by faxing
a signed counterpart of this Amendment to NBT (any party that effects delivery
in such manner hereby agreeing to transmit promptly to NBT an actual signed
counterpart).

EXECUTED as of the date first above written.

                                        BASIN EXPLORATION, INC.

                                        By: /s/  Neil L. Stenbuck
                                            ------------------------------
                                        Vice President/Chief Financial
                                          Officer


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                                        U.S. BANK NATIONAL ASSOCIATION f/k/a
                                        COLORADO NATIONAL BANK


                                        By:  /s/  Kathryn A. Gaiter
                                            ------------------------------
                                             Vice President

                                        NATIONSBANK OF TEXAS, N.A., in its
                                             capacity as a Lender and as Agent
                                             For Lenders


                                        By:   /s/David C. Rubenking
                                            ------------------------------
                                             Senior Vice President


                                        UNION BANK OF CALIFORNIA, N.A.


                                        By:  /s/
                                            ------------------------------
                                             Vice President


                                        By:  /s/
                                            ------------------------------
                                             Vice President