EXHIBIT 10.1

 
                                AMENDMENT NO. 1
                                      TO
                            VASTAR RESOURCES, INC.
                             ANNUAL INCENTIVE PLAN

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The Vastar Resources, Inc. Annual Incentive Plan (the "Plan") is hereby amended
effective March 10, 1999.

1.  Subsection 2(d) is hereby amended to read as follows:

          "(d)  "Committee" means (i) prior to a Change of Control, the
     Compensation Committee of the Board, and (ii) on and after a Change of
     Control, the Special Plan Administrator."

2.  Subsections (n), (o), (p), (q) and (r) are added to Section 2 of the Plan to
read as follows:

          "(n)  The term "Anticipatory Change of Control" shall be ascribed the
     meaning set forth for such term on Annex A attached hereto.

          (o) The term "Change of Control" shall be ascribed the meaning set
     forth for such term on Annex A attached hereto, but excluding an event
     described under paragraph (3) of the definition of such term on Annex A.

          (p) "Change of Control Trust" means the trust established by the
     Company to provide for the payment of any benefits, in whatever form is
     required, under the Plan on and after a Change of Control.

          (q) The term "Special Plan Administrator" shall be ascribed the
     meaning set forth for such term on Annex A attached hereto.

          (r) "Target AIP Award" means the target award determined by the
     Compensation Committee of the Board under the Vastar Resources, Inc. Annual
     Incentive   

 
     Plan for the relevant Plan Year, or if none was determined for
     that Plan Year, the most recent target award determined."

3.  Sections 7 through 9 are renumbered as Sections 8 through 10 and a new
Section 7 is added to the Plan to read as follows:

     "SECTION 7.  CHANGE OF CONTROL
          (a) Within 60 days following a Change of Control, each Participant
     shall be paid an amount equal to (i) (A) if the Change of Control occurred
     during the first six months of a Plan Year, an amount equal to 50 percent
     of the Participant's Target AIP Award for such Plan Year, and (B) if the
     Change of Control occurred during the second six months of a Plan Year, an
     amount equal to 100 percent of the Participant's Target AIP Award for such
     Plan Year, plus (ii) the Target AIP Award applicable to such Participant
     for the Plan Year ending immediately prior to the Change of Control if a
     specific Award has not been paid to such Participant with respect to such
     Plan Year.

          (b) Upon the earlier to occur of an Anticipatory Change of Control or
     a Change of Control, the Company or any successor to the obligations of the
     Company shall fund the Change of Control Trust in accordance with its
     terms."

3.  Subsection 8(a) of the Plan is amended to read as follows:

          "(a)  The Company intends to establish a grantor trust to aid in
     accumulating the amounts necessary to pay any amount awarded to any
     Participant for any Plan Year, and any Award deferred pursuant to Section 6
     or any interest credited thereon.  All Awards, and any interest credited
     thereon, shall be paid from the general funds of the Company or any
     successor to the obligations of the Company to the extent not paid from the
     grantor trust (including, if applicable, the Change of Control Trust).
     Under no circumstances shall a 

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     Participant or other person have any interest whatsoever in any particular
     property or assets of the Company as a result of this Plan or any Award
     made thereunder."

4.   Subsection 8(d) of the Plan is added to the Plan to read as follows:

          "(d)  Any action required to be taken under this Plan by the Chief
     Financial Officer and the General Counsel of the Company may be taken by
     either individual if the other position is then vacant, and if both
     positions are vacant, such action may be taken by any other officer of the
     Company with a position of vice president or above.  Any action required to
     be taken by the Vice President, Human Resources of the Company may, if such
     position is vacant, be taken by any other officer of the Company with a
     position of vice president or above."

5.  Section 9 of the Plan is amended to read as follows:

     "SECTION 9.  AMENDMENT, SUSPENSION OR TERMINATION

          (a) Amendment or Termination Generally.   Except as provided under
     Subsections 9(b) and (c), the Board may suspend, terminate or amend the
     Plan at any time.  Amendment, suspension or termination of the Plan shall
     not alter the amount of an Award accrued for a Plan Year and not yet paid
     prior to such amendment, suspension or termination.

          (b) Amendment or Termination During Anticipatory Change of Control.
     The Plan may not be terminated or amended during the period after the
     occurrence of an Anticipatory Change of Control and prior to a Change of
     Control or a written determination by the Chief Financial Officer and the
     General Counsel of the Company, approved by either the Board of Directors
     of the Company (the "Board"), the Outside circumstances shall a Directors
     or the Executive Committee of the Board, that an Anticipatory Change of
     Control has ended without concluding in a Change of Control, except that
     the Board may amend the Plan during such

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     a period as it may deem reasonably necessary provided, that if any such
     amendment reduces, or could reduce, the value of any benefit of a
     Participant, as determined in the sole discretion of the Special Plan
     Administrator, the Company or any successor to the obligations of the
     Company shall, prior to, and as a condition precedent to, such amendment
     going into effect, provide substantially equivalent value in replacement
     thereof to the Participant in the reasonable determination of the Special
     Plan Administrator.

          (c) Amendment or Termination on or After a Change of Control.  The
     Plan may not be amended or terminated on or after a Change of Control until
     all payments that may be due pursuant to Subsection 7(a) of the Plan, as
     determined in the sole discretion of the Special Plan Administrator of the
     Change of Control Trust, have been made, unless consent to such amendment
     is obtained from all of the Participants or, in the alternative, the
     Participants whose Plan benefits are affected by such amendment.  After a
     Change of Control the Plan will terminate upon the payment of all amounts
     due and payable under Section 7(a) hereof, provided, however, that such
     termination shall not affect any right of an Employee which shall have
     accrued prior to such termination."

     Executed as of the 10th day of March, 1999.



ATTEST                          VASTAR RESOURCES, INC.



By: /s/ Jonathan D. Edelfelt    By: /s/ Jeffrey M. Bender
   --------------------------      -------------------------------
   JONATHAN D. EDELFELT                  JEFFREY M. BENDER
   Associate Secretary                   Vice President
                                         Human Resources

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