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                             BASIN EXPLORATION, INC.
                              ONSHORE GEOSCIENTIST
                        OVERRIDING ROYALTY INTEREST PLAN

This Onshore 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 onshore area of the United
States.

1.       PLAN PARTICIPANTS. The persons covered by this Plan (individually a
         "Participant" and collectively the "Participants") shall be the Vice
         President of Onshore Exploration and any geologist, geophysicist, or
         other geoscientist employed by Basin as a member of Basin's onshore
         exploration group, and approved for inclusion in this Plan by the
         President (or other Chief Executive Officer of Basin) and the Vice
         President of Onshore 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.       A Participant shall become vested in Overriding Royalty
                  Interests (as hereinafter defined) as of the date and time
                  when a lease or working or operating interest therein covering
                  oil and gas in a Prospect Area in the area described in
                  Section 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 their
                  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 and at the time the Prospect Area is Designated as
                  provided below.

         B.       For purposes of this Section 2, 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 Section 4 shall be
                  deemed Acquired for purposes of this Section as to undeveloped
                  reserves upon the circulation of an AFE for the drilling or
                  other operation intended to explore for such undeveloped
                  reserves.

         C.       For purposes of this Section 2, a Prospect Area is defined as
                  a geographic area (i) located on the onshore area of the
                  United States, I.E., excluding any area covered by state or
                  federal waters off the coast of the United States except for
                  areas in state waters along the coastlines that are related to
                  or extensions of onshore areas worked by Basin's onshore
                  exploration group, (ii) covering a reservoir or other geologic
                  objective that (a) is expected to be tested by the drilling,
                  re-entry or



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                  recompletion of a well and (b) is designated as such
                  ("Designated") in writing by the Chief Executive Officer of
                  Basin based on his evaluation of the information submitted to
                  him by the Vice President of Onshore Exploration. Prospect
                  Areas can overlap in areal extent so long as the areas of
                  overlap do not include the same formations or zones. Generally
                  it is expected that Prospect Areas will be Designated (x) in
                  connection with Basin's internal Clearance To Drill procedure
                  preceding the drilling of an initial well in a Prospect Area,
                  or (y) in connection with Basin's execution of an agreement to
                  acquire an interest in a drill-ready Prospect Area from a
                  third party. However, the Chief Executive Officer shall have
                  the discretion to Designate a Prospect Area at any time he
                  believes appropriate based on the data available to him. A
                  Prospect Area shall not be deemed to include proved and/or
                  probable reserves identified as such in connection with an
                  acquisition by Basin as described in Section 4. The decision
                  of the Chief Executive Officer on when and whether to
                  Designate a Prospect Area and on the area and formations to be
                  included within a Prospect Area shall be based on such
                  criteria as he believes to be appropriate in his sole
                  discretion and shall be final and binding for all purposes of
                  this Plan.

         D.       If a Participant leaves Basin employment, the Chief Executive
                  Officer of Basin shall have the discretion to allocate either
                  to such Participant or to a succeeding Participant or to Basin
                  the Overriding Royalty Interest for which such terminated
                  Participant would have otherwise been eligible on any lease or
                  interest therein Acquired by Basin following the termination
                  of such Participant's employment in a Prospect Area that has
                  been Designated during such Participant's employment with
                  Basin.

3.       OVERRIDING ROYALTY INTEREST.

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

         B.       Such Overriding Royalty Interest shall be computed and paid in
                  accordance with the following:

                  1.       The Overriding Royalty Interest will be subject to
                           its proportionate shares of all gathering,
                           transportation, processing, treatment and other costs
                           of marketing production from the Working Interest
                           burdened thereby and will be subject to its
                           proportionate shares of all taxes assessed on or
                           measured

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                           by production attributable to such Working Interest.

                  2.       The Overriding Royalty Interest will be payable out
                           of and only out of oil and gas produced, saved and
                           marketed attributable to the Working Interest
                           burdened thereby.

                  3.       The Overriding Royalty Interest shall not, in any
                           event, be paid or accrued upon any oil, gas,
                           casinghead gas and other hydrocarbon substances used
                           for operating, development or production purposes on
                           the Working Interest burdened thereby or unavoidably
                           lost; or upon gas used in repressuring or recycling
                           operations or pressure maintenance operations
                           benefiting such Working Interest.

                  4.       Basin shall not have any duty or obligation to
                           develop or operate the Working Interests burdened by
                           the Overriding Royalty Interest for oil, gas and
                           other hydrocarbons other than in its sole discretion
                           nor to maintain in effect the burdened Working
                           Interests by the payment of delay rentals or the
                           performance of any other act.

                  5.       Basin will have, and will reserve from any assignment
                           of the Overriding Royalty Interest, the right to pool
                           or combine the Working Interests burdened thereby and
                           leases and lands covered thereby or any part thereof,
                           in such manner and to such extent as Basin shall
                           determine, with other lands and leases into voluntary
                           units, or into units established by any governmental
                           authority having jurisdiction whenever, in the
                           judgment of Basin, it is necessary or advisable to do
                           so in order properly to explore or develop all or any
                           portion of the affected Working Interests or to
                           promote the conservation of oil or gas therefrom; and
                           if a Working Interest or any part thereof is pooled
                           accordingly, then the Overriding Royalty Interest
                           burdening such Working Interest shall be reduced
                           proportionately to and payable only in the ratio that
                           the acreage burdened by such Overriding Royalty
                           Interest bears to all acreage included in any such
                           pooled unit.

                  6.       The Overriding Royalty Interests will be subject to
                           the provisions of any operating agreement now or
                           hereafter covering the Working Interests burdened
                           thereby, and in the event Basin goes nonconsent on
                           any operation pursuant to any such operating
                           agreement, the Overriding Royalty Interest shall be
                           deemed suspended to the extent any such operating
                           agreement would require Basin to bear such overriding
                           royalty notwithstanding its failure to participate in
                           the production burdened by such override.

4.       AFFECTED LEASE OR PROSPECT AREA. The Overriding Royalty Interest shall
         burden all leases or Working Interests therein Acquired (whether by
         purchase, farm-in or in any other manner) by the Burdened Group
         subsequent to the effective date of this Plan in Prospect Areas
         Designated subsequent to the effective date of this Plan, subject,
         however, to the following exceptions:

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         A.       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 included within a Prospect
                  Area or 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, Prospect
                  Areas may be Designated covering such portion of the lease
                  that includes other reserves discovered by subsequent
                  exploration on the lease by the Burdened Group.

         B.       The Overriding Royalty Interest shall burden interests
                  Acquired prior to the effective date of this Plan in the
                  Prospect Areas described in Exhibit A attached hereto as well
                  as interests in such Prospect Areas Acquired after the
                  effective date of this 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, then
         subject to Paragraph 2.D. above, Basin shall automatically reallocate
         the interests of the Participants effective on such Confirmation or
         termination date to compensate for the new 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.

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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 "B". 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-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

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         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 Onshore Geoscientist Overriding Royalty
Interest Plan was adopted by the Company effective this 24th day of August,
1999.


                                       BASIN EXPLORATION, INC.


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




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