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                             BASIN EXPLORATION, INC.
                             GULF COAST GEOSCIENTIST
                        OVERRIDING ROYALTY INTEREST PLAN
                           (Amended November 10, 1999)


This Gulf Coast Geoscientist Overriding Royalty Interest Plan (the "Plan")
shall set forth the terms of the program established by Basin Exploration,
Inc. ("Basin") for assignment of overriding royalty interests into
geoscientists Basin employs to explore for oil and gas in the offshore area
of the Gulf of Mexico.

1.       PLAN PARTICIPANTS. The persons covered by this Plan (individually a
         "Participant" and collectively the "Participants") shall be the Vice
         President of Gulf Coast Exploration and any geologist, geophysicist, or
         other geoscientist employed by Basin as a member of Basin's Gulf Coast
         offshore exploration group, and approved for inclusion in this Plan by
         the President (or other Chief Executive Officer of Basin) and the Vice
         President of Gulf Coast Exploration. A Participant's participation in
         the Plan shall not be effective until it is confirmed in writing by the
         President or Chief Executive Officer delivered to the Participant
         ("Confirmation").

2.       INTERESTS VESTED. A Participant shall become vested in Overriding
         Royalty Interests (as hereinafter defined) as of the date and time when
         a lease or other interest therein covering oil and gas in the area
         described in paragraph 4 below is acquired (whether by purchase, farmin
         or in any other manner) by Basin, its investors or program
         participants, and/or by third parties acquiring therein interests by,
         through or under Basin and/or its investors or program participants
         (individually, a "Burdened Party" and collectively the "Burdened
         Group") provided that the Participant is an employee of Basin at the
         time of such acquisition. For purposes of this paragraph, a lease
         acquired at a lease sale pursuant to a bid submitted by Basin or a
         Burdened Party acting pursuant to an agreement with Basin shall be
         deemed acquired on the date of the lease sale if the lease is awarded
         to Basin or a Burdened Party pursuant to that lease sale; a lease
         acquired pursuant to a farm-in or other agreement shall be deemed
         acquired on the date the agreement has been executed by all parties;
         and a lease with developed reserves acquired by the Burdened Group as
         described in paragraph 4 shall be deemed acquired for purposes of this
         paragraph as to undeveloped reserves upon the circulation of an AFE for
         the drilling, or other operation intended to explore for such
         undeveloped reserves.

3.       OVERRIDING ROYALTY INTEREST. The overriding royalty interest awarded
         hereunder (the "Overriding Royalty Interest") shall be a maximum of two
         and one-half percent (2.5%) of the full undivided Working Interests
         acquired in a lease by the Burdened Group (as such Working Interests
         may be enlarged or reduced in accordance with the terms and conditions
         under which such interests are so acquired, and proportionately reduced
         to the extent the lease covers less than the full and undivided
         interest in the oil and gas mineral estate covered thereby). Such
         Overriding Royalty Interest shall be computed in the same manner as the
         lessor's royalty under the lease burdened by such Overriding Royalty
         Interest. For purposes of this Plan, "Working Interest" shall mean the
         full or undivided cost-bearing interest in a lease which determines the
         entitlement of the

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         owner thereof to a share of proceeds of production from the lease.

4.       AFFECTED LEASE OR ACREAGE. The Overriding Royalty Interest shall burden
         all leases or interests therein acquired (whether by purchase, farm-in
         or in any other manner) by the Burdened Group on the Outer Continental
         Shelf offshore of Texas, Louisiana, Alabama, and Florida and in state
         waters subsequent to the effective date of this Plan subject, however,
         to the following exception: In the event the Burdened Group acquires,
         by virtue of a producing property acquisition or exchange or other
         transaction involving the exchange of consideration for existing
         developed reserves, an interest in a lease covering proved and/or
         probable reserves which are identified as such by the seller at the
         time the lease is acquired, such leasehold interest shall not be
         burdened by or subject to the Overriding Royalty Interest insofar as
         such lease covers and includes such proved and/or probable reserves. In
         such case, however, the Overriding Royalty Interest shall burden such
         portion of the lease that covers or includes other reserves discovered
         by subsequent exploration on the lease by the Burdened Group. In
         addition, leases or interests therein acquired by the Burdened Group in
         state waters along the coastlines of the Gulf of Mexico that are within
         Prospect Areas established under Basin's Onshore Geoscientist
         Overriding Royalty Plan (the "Onshore ORI Plan") shall not be burdened
         by the Overriding Royalty Interest granted under this Plan. In general,
         it shall be presumed that Basin's offshore exploration group shall have
         primary responsibility for exploring in state waters along the
         coastlines of the Gulf of Mexico except for those areas that are
         related to or extensions of onshore areas worked by Basin's onshore
         exploration group, but the Chief Executive Officer of Basin shall
         determine whether and the extent to which such areas are to be subject
         to this Plan or to the Onshore ORI Plan.

5.       PROSPECT SWAPS. If the Burdened Group or a Burdened Party trades or
         exchanges a leasehold interest in acreage burdened by the Overriding
         Royalty Interest for a leasehold interest in other acreage from a third
         party, upon request by the Burdened Group the Participants will
         relinquish their Overriding Royalty Interests in the interest traded by
         the Burdened Group if the Participants receive the Overriding Royalty
         Interest on the interest received by the Burdened Group in exchange.

6.       ALLOCATION OF THE OVERRIDING ROYALTY INTEREST. The Participants shall
         be allocated and severally share 100 percent of the aggregate
         Overriding Royalty Interest described in paragraph 3 above, provided,
         however, the Overriding Royalty Interest shall never exceed
         five-eighths of one percent (0.625%) for each Participant. Each
         Participant shall be entitled to an equal share of the Overriding
         Royalty Interest, subject to the 0.625% individual limitation and 2.5%
         aggregate limitation, regardless of the number of Participants entitled
         to share in such Overriding Royalty Interest, provided that the
         Participants are employed by Basin when the Working Interest burdened
         by the Overriding Royalty Interest is acquired by the Burdened Group in
         the manner provided above.

         The number of Participants in the Plan may vary from time to time. When
         the number of Participants changes as a result of a Confirmation of a
         new Participant or the termination of a Participant's employment, Basin
         shall automatically reallocate the interests of the Participants
         effective on such Confirmation or termination date to compensate for
         the new

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         number of Participants so that the Overriding Royalty Interests vesting
         after the reallocation effective date shall reflect the inclusion or
         exclusion (as the case may be) of the new or terminated Participant,
         provided, however, that Basin's reallocation of the Overriding Royalty
         Interests shall have no effect upon any Participant's Overriding
         Royalty Interests which have vested prior to the effective date of such
         reallocation.

7.       TERMINATION. The rights granted to a Participant pursuant to this Plan
         shall automatically terminate upon the end of such Participant's
         employment with Basin subject to the following:

         a) A Participant's termination shall have no effect upon such
         Participant's Overriding Royalty Interests to the extent such interests
         have been vested in the Participant prior to his date of termination
         regardless whether the Participant has received an assignment of the
         Overriding Royalty Interests; and

         b) Upon demand, Basin will, or will cause the Burdened Parties to,
         execute and deliver to the Participant appropriate instruments of
         assignment with respect to the Participant's portion of the Overriding
         Royalty Interests which have been vested prior to the Participant's
         date of termination.

8.       RECORDABLE ASSIGNMENTS. Basin will, or will cause the Burdened Parties
         to, make appropriate instruments of assignment of Overriding Royalty
         Interests on affected leases into the Participants in recordable form
         and in a timely manner utilizing a form of assignment similar to that
         attached hereto as Exhibit "A". It is recognized and acknowledged that
         some leases may be subject to contractual limitations or restrictions
         upon the right of the Burdened Group to make the recordable form
         assignments and to such extent it is agreed that notwithstanding the
         inability of the Burdened Group to make such assignments to the
         Participants, Basin will nevertheless account to the Participants to
         the same extent and effect as though such assignments had in fact been
         executed and delivered and will pay or cause them to be paid to the
         Participants accordingly.

9.       AMENDMENT. Basin, at its sole option and discretion, but only after
         giving written notice to the Participants, may terminate, amend or
         otherwise revise this Plan as to all lease or interests therein
         acquired after the date of such notice.

10.      SUCCESSORS. This Plan shall be binding upon and shall inure to the
         benefit of the Participants and their respective heirs and legal
         representatives, and Basin and its successors. The term "successor"
         shall mean any person, firm, corporation or other business entity that,
         at any time whether by merger, acquisition or otherwise, acquires all
         or substantially all of the stock, assets or business of Basin.

11.      EMPLOYMENT RELATIONSHIP.  Nothing contained in this Plan or in any
         Confirmation letter received by a Participant shall restrict or
         otherwise interfere with Basin's discretion with respect to the
         termination of any Participant's employment.

12.      NON-ASSIGNABILITY. Each Participant's rights under this Plan shall be
         non-

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         transferable except by will or by the laws of descent and
         distribution and except insofar as applicable law may otherwise
         require. Subject to the foregoing, no right, benefit or interest
         hereunder shall be subject to anticipation, alienation, sale,
         assignment, encumbrance, charge, pledge, hypothecation, or set-off in
         respect of any claim, debt or obligation, or to execution, attachment,
         levy or similar process, or assignment by operation of law, and any
         attempt, voluntary or involuntary, to effect any such action shall, to
         the full extent permitted by law, be null, void and of no effect.
         Nothing in this paragraph shall prevent a Participant from assigning or
         otherwise transferring any interest in vested Overriding Royalty
         Interests to any party.

13.      SEVERABILITY. In the event that any provision or portion of this Plan
         shall be determined to be invalid or unenforceable for any reason, the
         remaining provisions and portions of the Plan shall be unaffected
         thereby and shall remain in full force and effect to the fullest extent
         permitted by law.

14.      DELAWARE LAW TO GOVERN. All questions pertaining to the construction,
         regulation, validity and effect of the provisions of this Plan shall be
         determined in accordance with the laws of the State of Delaware without
         regard to the conflict of law principles thereof.


         IN WITNESS WHEREOF, this Gulf Coast Geoscientist Overriding Royalty
Interest Plan was adopted by the Company effective this 30th day of November
1995.


                                       BASIN EXPLORATION, INC.


                                       By:
                                          ----------------------------
                                          Michael S. Smith, President



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