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                                                                    EXHIBIT 10.5

                          WHITING PETROLEUM CORPORATION

                          PRODUCTION PARTICIPATION PLAN

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                          WHITING PETROLEUM CORPORATION

                          PRODUCTION PARTICIPATION PLAN

                                    PREAMBLE

        WHITING PETROLEUM CORPORATION, a Delaware corporation (the "Company"),
hereby establishes the following production participation plan (the "Plan"). The
Plan is intended to provide greater incentives to the Company's employees to
increase the profitability of the Company and to enable the Company to attract,
motivate and retain valuable employees upon whom, in large measure, the
continued profitability of the Company depends.

                                    ARTICLE I

                                   Definitions

        The following words and phrases shall have the meaning set forth below
unless the context clearly indicates otherwise:

        1.1     "Committee" means the Administrative Committee provided for in
section 5.2.

        1.2     "Company" means Whiting Petroleum Corporation and any successor
thereto.

        1.3     "Compensation" means the total salary paid or accrued to a
Participant by the Company or a wholly owned subsidiary of the Company during a
Plan Year, excluding bonuses, reimbursed expenses and other extraordinary items.

        1.4     "Effective Date" means January 1, 1981.

        1.5     "Employee" means each common-law salaried Employee of the
Company or a subsidiary of the Company who performs services for the Company or
a subsidiary on a full-time basis, as determined by the Company.

        1.6     "Participant" means an Employee, or former Employee, who is
eligible to receive distributions in accordance with the terms of the Plan.

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        1.7     "Plan Year" means the twelve-month period on which the records
of the Plan are kept, which shall be the same as the fiscal year of the Company.

        1.8     Pronouns: Gender and Number. Unless the context clearly
indicates otherwise, words in any gender shall include the other genders and the
singular shall include the plural and vice versa.

                                   ARTICLE II

                            Participation in the Plan

        2.1     Participation.

                Each Employee of the Company shall become a Participant in the
Plan on his date of employment by the Company.

        2.2     Enrollment - Procedure.

                Each Participant shall fill out and sign an enrollment form
supplied by the Committee and return it to the Committee. The enrollment form
shall state, among other information, the Participant's post office address and
date of birth and a designation of the names and post office addresses of his
beneficiaries.

        2.3     Absences.

                A leave of absence approved in writing by the Company shall not
constitute a termination of employment for purposes of computing years of
service with the Company for determining vesting under section 4.3.

                                   ARTICLE III

                              Company Contributions

        3.1     Allocation of Royalty Interests to the Plan.

                (a)     Effective as of January 1, 1981, and continuing for the
duration of the Plan, the Company shall allocate on its books, for Plan
purposes, the following amounts:

                        (i)     With respect to all onshore, non-federal oil and
gas leases located in the United States in which the Company acquires a working
interest, except leases located in Alaska, the Company shall allocate an amount
equal to an overriding royalty of two percent (2%) of 8/8ths or the equivalent
of such a royalty. The amount of such overriding royalty shall be dedicated to
the Plan effective as of the date of acquisition by the Company. To

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the extent the acquired interest of the Company in a lease is less than one
hundred percent (100%) or 8/8ths as a result of the joint acquisition of a lease
by the Company and other non-affiliated parties, the royalty dedicated to the
Plan shall be proportionately reduced; and

                        (ii)    With respect to all federal, off-shore United
States, Alaskan and foreign oil and gas leases, contracts and concessions,
royalty or overriding royalty interests, or producing properties in which the
Company acquires an interest, the Company, at its sole discretion and option,
may allocate up to a two percent (2%) of 8/8ths overriding royalty, or the
equivalent thereof, or any other interest, such as a net profits interest, to
the Plan; and

                        (iii)   Notwithstanding the foregoing, properties
acquired by the Company prior to January 1, 1981 will be totally excluded from
the Plan.

                (b)     If considered necessary by the Company for sound
business reasons, the overriding royalty with respect to a particular property
or properties may be established by the Company at its sole discretion at an
amount less than two percent. The Company's Board of Directors shall allocate
interests to the Plan at least once each Plan Year and all allocations shall be
made on a well by well basis. In cases where the Company receives income from
unit arrangements under which the amount of income attributable to particular
wells cannot be ascertained, the amount of income allocable for Plan purposes
shall be determined by the Company's Board of Directors in its sole discretion.
The Company shall not be considered to own a beneficial interest in properties
to which it holds title as the nominee for others.

                (c)     Interests in wells allocated to the Plan which are
either spudded or purchased during each Plan Year shall form a separate
accounting pool (the "Pool") and the net income attributable to each year's Pool
shall be allocated and accounted for separately. Proceeds received by the
Company with respect to interests which have been allocated to a Pool shall be
distributed annually in accordance with Article IV, but less accrued taxes
measured by production, such as severance and production taxes, and less accrued
taxes imposed by the Windfall Profit Tax Act of 1980, which are applicable to
the income allocable to the Plan. The taxes applicable to such income shall be
calculated solely on an estimated basis by the Company using the same method
that the Company uses to estimate taxes for other financial accounting purposes.
No adjustment shall be made to reflect any difference between such estimates and
taxes actually imposed with respect to such income.

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        3.2     Sale of Interests.

                If the Company sells or transfers its interest in a well
(including the spacing unit on which such well is located) that is being used to
determine the amount of Plan income pursuant to section 3.1, that portion of the
net profit from such sale, before income taxes, attributable to the production
interest allocated to the Plan shall be distributable to the Participants
eligible to share in income distributions from the Pool in question in the same
manner as current income from production.

                                   ARTICLE IV

                    Allocation and Distribution of Net Income

        4.1     Allocation of Current Pool Net Income.

                As of the last day of each Plan Year, beginning with the Plan
Year ending December 31, 1981, the Committee shall allocate the accrued net
income allocable to the Pool created for that Year among the Participants
employed by the Company on the last day of that Plan Year in the following
manner:

                (a)     Thirty-three and one-third percent (33-1/3%) of the net
income of each Year's current Pool shall be allocated among the Participants in
the proportion which the Compensation of each Participant for such Year bears to
the total Compensation of all Participants for such Plan Year.

                (b)     Up to sixty-six and two-thirds percent (66-2/3%) of the
net income of each Year's current Pool shall be available for allocation among
any Participants who receive points pursuant to this section 4.1(b). Up to 666
points may be awarded annually based upon each Participant's contributions to
the Company with respect to that Plan Year. However, there is no requirement
that any points be awarded with respect to any given Plan Year. Points will be
awarded only to Participants who have put forth extraordinary effort on behalf
of the Company in cases where the Company has materially benefited from such
effort. The Committee shall furnish annually to the Company's Board of Directors
a recommended list of point allocations for eligible Participants (other than
members of the Committee). The Company's Board of Directors shall then determine
the points to be awarded to all eligible Participants, including those Committee
members who are also eligible Participants. The determination of the Company's
Board of Directors as to whether to award any points during a given Plan Year,
and

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as to the points awarded to each eligible Participant, shall be solely within
the discretion of the Board, and all decisions of the Board shall be final and
binding on all Participants and beneficiaries. All decisions with respect to the
award of points shall remain confidential.

                The portion of such sixty-six and two-thirds percent of the
Pool's net income to be allocated to each Participant receiving points shall be
equal to the percentage that the Participant's points are of the 666 possible
points for that Plan Year. If fewer than 666 points are awarded during any Plan
Year, the unallocated portion of the sixty-six and two-thirds percent of the net
income for that Plan Year shall be allocated and paid to Participants in the
same proportion as the amounts paid under section 4.1(a).

        4.2     Allocation of Prior Pool Net Income.

                The accrued net income for each Plan Year allocable to each
separate Pool formed under the Plan during prior Plan Years shall be allocated
only among those Participants who originally shared in the allocation of the net
income of such Pool pursuant to section 4.1 (or their beneficiaries) and who are
either employed by the Company as of the last day of the latest Plan Year or are
vested in accordance with section 4.4. The accrued net income attributable to
each prior Pool shall be allocated among those persons eligible to share in such
income based upon their original sharing ratios in such Pool, but increased
proportionately to account for the forfeiture of interests because of (a) the
termination of employment of Participants prior to becoming fully vested in
accordance with section 4.4, or (b) those matters specified in section 4.5.

        4.3     Distribution of Net Income.

                As soon as practicable after the end of each Plan Year,
beginning with the Plan Year ending December 31, 1981, the Company shall
distribute to each Participant (or his beneficiary) in one lump sum his
allocable share of the net income of the Plan for the preceding Plan Year, less
any required withholding of income taxes or other amounts applicable to payments
made to Employees of the Company.

        4.4     Vesting.

                (a)     If a Participant with fewer than one full year of
employment with the Company terminates employment with the Company for any
reason, he shall cease to be a Participant in this Plan and all rights of such
Employee under this Plan shall terminate. A Participant who is credited with one
or more full years of employment with the Company at the

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date of his termination of employment shall continue to participate in the Plan
on a vested basis in accordance with the following schedule:

                                                Vested Percentage
        Full Years of Employment                of Future Income
        ------------------------                -----------------
                   1                                    20%
                   2                                    40%
                   3                                    60%
                   4                                    80%
                   5                                   100%

A vested Participant shall continue to share in the distribution of accrued net
income from Pools in which he originally shared in the same manner as
Participants who are employed by the Company, based upon his vested percentage
at the date of his termination of employment and his percentage of the net
income of each such Pool as of the end of the Plan Year immediately preceding or
coincident with the date of his termination of employment. For purposes of this
section, employment prior to January 1, 1981 shall be disregarded and only full
Plan Years of employment after January 1, 1981 shall be credited to
Participants.

                (b)     If a Participant dies or becomes disabled (as determined
by the Committee) prior to becoming fully vested in accordance with (a) above,
such Participant (or his beneficiary) shall nevertheless be fully vested for
purposes of future distributions from the Plan and shall be entitled to receive
future distributions of Plan income in accordance with section 4.4(a).

        4.5     Forfeiture-Termination for Cause.

                (a)     If a Participant's employment with the Company is
terminated for cause, as determined by the Company, the Participant, regardless
of his or her vested percentage, shall not be entitled to any further
distributions or payments from the Plan.

                (b)     If a vested terminated Participant is later determined
by the Company to have engaged in any activity which would be grounds for
termination for cause while employed by the Company, such Participant shall,
upon such determination, forfeit all rights to any further payments from the
Plan.

        4.6     Purchase of Interests by Company.

                The Company may, at its sole option, purchase the entire vested
interest under the Plan of any terminated or deceased Participant if such
interest produced $1,000 or less income for the Plan Year preceding the date of
purchase. The Company shall notify the

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terminated Participant, or the beneficiary of a deceased Participant, within 120
days after the end of any Plan Year, of its election to purchase such person's
interest under the Plan. Payment for any interest so purchased shall be made by
the Company, by its check, within 60 days after the expiration of said notice
period. The purchase price of any interest so purchased shall be based on the
fair market value of the Participant's (or beneficiary's) interest under the
Plan as of the end of the immediately preceding Plan Year. The determination of
fair market value shall be made by the Company, using the valuation reports,
discount rates and other factors then being used by the Company for the purchase
of oil and gas interests from third parties.

                                    ARTICLE V

                  Allocation of Administrative Responsibilities

        5.1     The Company.

                The Company shall be responsible for: (a) keeping accurate books
and accounts with respect to all income which it receives attributable to
interests which have been allocated to the Plan; (b) keeping accurate books and
records with respect to its Employees and their Compensation and furnishing such
data to the Committee; and (c) making payments to Plan Participants and their
beneficiaries in accordance with the provisions of the Plan.

        5.2     The Committee.

                The Board of Directors of the Company shall appoint an
administrative Committee composed of at least two, but no more than seven,
persons who may, but need not be, Employees of the Company or Participants. The
Committee shall administer the Plan and shall have all powers necessary for that
purpose, including, but not by way of limitation, power to interpret the Plan,
to determine the eligibility, status and rights of all persons under the Plan
and in general to decide any dispute. The Committee shall direct all
distributions in accordance with the provisions of the Plan and shall maintain
all Plan records except records required to be kept by the Company.

        5.3     Organization of Committee.

                The Committee shall elect a chairman and shall adopt such rules
as it deems desirable for the conduct of its affairs and for the administration
of the Plan. It may appoint agents (who need not be members of the Committee) to
whom it may delegate such powers as it deems appropriate, except that any
dispute shall be determined by the Committee.

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The Committee may make its determinations with or without meetings. It may
authorize one or more of its members or agents to sign instructions, notices and
determinations on its behalf. The action of a majority of the Committee shall
constitute the action of the Committee.

        5.4     Indemnification of Committee Members.

                The Company shall indemnify each member of the Committee against
any and all claims, loss, damages, expense and liability arising from any action
or failure to act with respect to the Plan, except when the same is judicially
determined to be due to the gross negligence or willful misconduct of such
person.

                                   ARTICLE VI

                            Termination and Amendment

        6.1     Termination of Plan and Discontinuance of Contributions.

                The Company presently intends to continue the Plan indefinitely,
but the continuance of the Plan is not assumed as a contractual obligation and
the Company may terminate the Plan at any time by delivering written notice of
termination to the Committee and each Participant and beneficiary then entitled
to receive distributions from the Plan. Upon the termination of the Plan, or
upon the sale or exchange of all or substantially all of the Company's assets,
or the merger of the Company (if the Company is not the surviving entity), or
upon the liquidation of the Company, the interests of all Participants in the
Plan shall become fully vested, notwithstanding any other provision hereof.

        6.2     Procedure Upon Termination.

                Upon voluntary termination of the Plan by the Company, the
Committee shall either (a) distribute to each Participant or beneficiary then
participating in the Plan, in one lump sum or in five equal installments with
interest at the minimum rate required in order to avoid the imputation of
interest under Section 483 of the Internal Revenue Code, or any successor
provision, an amount equal to the then present worth of each such person's
interests in the Plan, computed in accordance with section 4.6, or (b) continue
to make distributions in accordance with the provisions of the Plan from all
Pools existing at the time of termination, all as the Committee in its sole
discretion may determine. If the Plan terminates automatically because of one of
the events specified in section 6.1, the interest of each person, valued in
accordance with section 4.6, shall be distributed in one lump sum. Upon
termination of the Plan,

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the interest of each Participant or beneficiary in each Pool under the Plan
shall be 100% vested and shall be the percentage interest of each such person in
that Pool as of the end of the last Plan Year prior to termination of the Plan,
adjusted to account for any forfeitures between the end of the prior Plan year
and the time of termination of the Plan.

        6.3     Amendment by Company.

                The Company may at any time amend the Plan in any respect by
action of its Board of Directors, but no amendment shall be made which would
have the effect of materially and adversely affecting the interest of any person
under the Plan with respect to then existing Pools.

                                   ARTICLE VII

                                  Miscellaneous

        7.1     Right to Dismiss Employees.

                The Company may terminate the employment of any Employee as
freely and with the same effect as if this Plan were not in existence.

        7.2     Withholding of Taxes, Etc.

                The Company shall withhold from all payments to Participants and
beneficiaries hereunder, and pay to the appropriate governmental authority, all
amounts of income taxes and other amounts which are required by applicable law
and regulation to be withheld from wage payments to Employees of the Company.

        7.3     Source of Benefits.

                All benefits payable under the Plan shall be paid solely from
the general assets of the Company and no allocation of royalty interest or
income on the books of the Company shall be deemed to create a separate fund or
any ownership interest on the part of the Plan in any properties being used to
measure Plan income or in any production from such properties.

        7.4     Ownership of Properties.

                Nothing contained in this Plan shall in any way restrict the
right of the Company to sell, transfer, mortgage, encumber or otherwise deal
with the properties giving rise to the revenues used to measure Plan income.

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        7.5     Beneficiaries.

                Each Participant shall file with the Committee a designation of
the beneficiaries and contingent beneficiaries to whom income attributable to
his interest under the Plan shall be paid in the event of his death. Such
designation may be changed by the Participant at any time and without the
consent of any previously designated beneficiary. In the absence of an effective
beneficiary designation as to any portion of a Participant's interest under the
Plan, income attributable to such interest shall be paid to the Participant's
personal representative, but if the Committee believes that none has been
appointed within six months after the Participant's death, the Committee may
direct that such income shall not be paid until a personal representative has
been appointed or may direct that such income shall be paid to the Participant's
surviving spouse, or if there is none, to his surviving children and issue of
deceased children by right of representation, or if there be none, to his
surviving parents.

        7.6     Non-transferability of Benefits.

                No Participant or beneficiary shall have any right to assign,
alienate, transfer, hypothecate, encumber or anticipate his interest in any
benefits under this Plan, nor shall such benefits be subject to any legal
process to levy upon or attach the same for payment of any claim against any
such Participant or beneficiary.

        7.7     Payments Due Minors or Incapacitated Persons.

                If any person entitled to a payment under the Plan is a minor,
or if the Committee determines that any such person is incapacitated by reason
of physical or mental disability, whether or not legally adjudicated as such,
the Committee shall have the power to cause the payments becoming due to such
person to be made to his personal representative or to another for his benefit,
without responsibility of the Committee to see to the application of such
payments. The Committee shall have no responsibility to investigate the physical
or mental condition of a Participant and any determination of disability made by
the Committee shall be binding on the Participant and all other persons.
Payments made pursuant to such power shall operate as a complete discharge of
the Plan, the Company and the Committee.

        7.8     Disposition of Unclaimed Payments.

                Each Participant must file with the Committee from time to time
in writing his post office address and the post office address of each of his
beneficiaries and each change of post office address. Any communication,
statement or notice addressed to a Participant or

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beneficiary at his last post office address filed with the Committee, or if no
address is filed with the Committee, then at his last post office address as
shown on the Company's records, will be binding in the Participant and his
beneficiaries for all purposes of the Plan. Neither the Committee nor the
Company shall be required to search for or locate a Participant or beneficiary.
If the Committee notifies a Participant or beneficiary that he is entitled to a
distribution and also notifies him of the provisions of this section, and the
Participant or beneficiary fails to make his address known to the Committee
within three calendar years after the notification, the interest in each Pool
under the Plan of the Participant or beneficiary will be forfeited as of the end
of the Plan Year following the expiration of such three-year period and
re-allocated among the Participants in each Plan Pool at that time.

        7.9     Governing Law.

                The construction and interpretation of this Plan shall be
governed by the laws of the State of Colorado.

DATE:  September 1, 1981

ATTEST:                                         WHITING PETROLEUM CORPORATION


/s/ Patricia J. Butler                          By:  /s/  Kenneth R. Whiting
----------------------------                        ----------------------------
                                                    President

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