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                                                                   Exhibit 10.15

                        AMENDMENT TO EMPLOYMENT AGREEMENT

THIS AMENDMENT TO EMPLOYMENT AGREEMENT is entered into this 12th day of May,
1999, between BASIN EXPLORATION, INC., a Delaware corporation (the
"Corporation"), and PATRICK A. JACKSON (the "Officer").

         The Corporation and the Officer have previously entered into an
Employment Agreement dated as of January 28, 1999 (the "Employment Agreement")
and desire to amend the Employment Agreement to clarify certain provisions
regarding compensation payable to the Officer in the event of a Change of
Control as defined in the Employment Agreement.

         NOW, THEREFORE, in consideration of the premises and for good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties agree as follows:

         1.       DEFINED TERMS. All terms used and not defined herein shall
have the meaning given them in the Employment Agreement.

         2.       DELETION OF SECTION 2.7(c). Section 2.7(c) of the Employment
Agreement is deleted.

         3.       LIMITATION ON AMOUNT OF PAYMENT. A new Section 4.1(f) is added
to the Employment Agreement to read as follows:

         (f)      LIMITATION OF CHANGE OF CONTROL PAYMENTS.

                  (i)      Notwithstanding anything else in this Agreement,
                           solely in the event of a termination by the
                           Corporation without Cause or a termination by the
                           Officer for Good Reason, and except as provided in
                           subsection (a) below, the aggregate of the payments
                           of benefits to which the Officer will be entitled
                           under Section 4.1(c) will be reduced to the extent
                           necessary so that the Officer will not be liable for
                           the federal excise tax levied on certain "excess
                           parachute payments" under section 4999 of the
                           Internal Revenue Code.

                                    (a) The limitation of Section 4.1(f)(i) will
                                    not apply if the difference between (w) the
                                    present value of all payments to which the
                                    Officer is entitled under Section 4.1(c)
                                    determined without regard to Section
                                    4.1(f)(i) less (x) the present value of all
                                    federal, state and other income and excise
                                    taxes for which the Officer is liable as a
                                    result of such payments exceeds the
                                    difference between (y) the present value of
                                    all payments to which the Officer is
                                    entitled under Section 4.1(c) calculated as
                                    if the limitation of Section


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                                    4.1(f)(i) applies less (z) the present value
                                    of all federal, state and other income and
                                    excise taxes for which the Officer is liable
                                    as a result of such reduced payments.
                                    Present values will be determined using the
                                    interest rate specified in section 280G of
                                    the Internal Revenue Code and will be the
                                    present values as of the date on which the
                                    Officer's employment terminates (unless it
                                    is necessary to use a different date in
                                    order to avoid adverse consequences under
                                    section 280G).

                  (ii)     DETERMINATION BY OFFICER. Whether payments to the
                           Officer are to be reduced pursuant to Section
                           4.1(f)(i), and the extent to which they are to be so
                           reduced, will be determined by the Officer. The
                           Officer may, at the expense of the Company, hire an
                           accounting firm, law firm or employment consulting
                           firm selected by the Officer to assist him in such
                           determination. If a reduction is made pursuant to
                           Section 4.1(f)(i), the Officer will have the right to
                           determine which payments and benefits will be
                           reduced.

                  (iii)    ADDITIONAL BENEFIT. The Officer shall receive the
                           benefit of any change made by the Corporation in the
                           calculation or entitlement of severance compensation
                           following a Change of Control for any other officer
                           of the Corporation, such as an agreement by the
                           Corporation to "gross up" the compensation paid to an
                           officer by paying the excise tax imposed by Section
                           280G of the Internal Revenue Code .

         4.       EFFECT OF AMENDMENT. As amended hereby, the Employment
Agreement remains in full force and effect.

         IN WITNESS WHEREOF, the parties have executed this Amendment to
Employment Agreement on the day and year first above entered.


                                                BASIN EXPLORATION, INC.


                                                By
                                                  ------------------------------
                                                   President




                                                --------------------------------
                                                PATRICK A. JACKSON