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                                EXHIBIT 10(a)(i)



                          CHIEFTAIN INTERNATIONAL, INC.

                                 RETIREMENT PLAN


                             AS AMENDED MAY 15, 1997
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RETIREMENT PLAN                                                           PAGE 2
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                                TABLE OF CONTENTS



Section 1 - Interpretation ..............................................3

Section 2 - Establishment of the Plan ....................................7

Section 3 - Participation in the Plan ...................................7

Section 4 - Contributions ...............................................9

Section 5 - Establishment of Accounts ..................................11

Section 6 - Retirement..................................................12

Section 7 - Forms of Retirement Benefits ...............................13

Section 8 - Death Prior to Retirement ..................................14

Section 9 - Termination of Service ......................................16

Section 10 - Administration of the Plan .................................17

Section 11 - Retirement Trust Fund .....................................18

Section 12 - Amendment or Termination of the Plan ......................18

Section 13- General Conditions .........................................19
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SECTION 1 - INTERPRETATION

1.01  WORDS AND PHRASES

      For the purposes of this Plan, as the context may
      require, the expressions set out in this Section 1 shall have the meanings
      ATTRIBUTED THERETO.

1.02  BENEFICIARY has the meaning ascribed thereto in Section 8.05.

1.03  CANADA PENSION PLAN means the Canada Pension Plan, RSC 1985 c. C-8, or as
      thereafter amended, or any successor or similar legislation or plan
      instituted by the Government of Canada or a province of Canada.

1.04  COMPANY means Chieftain International, Inc. acting through its Board of
      Directors or such person or persons authorized by the Board of Directors
      so to act for the purposes of the Plan.

1.05  CONTINUOUS SERVICE means service with the Employer rendered by an Employee
      from the Employee's date of last employment with the Employer to the date
      of his termination of service, whether by death, Retirement, or otherwise.
      Continuous Service shall also include service rendered with Chieftain
      Development Co. Ltd. or Alberta Energy Company Ltd. which immediately
      precedes a period of Continuous Service with the Employer. Continuous
      Service shall not be broken by:

            (1)         any leave of absence of an Employee from his duties with
                        the consent of the Employer providing such leave is with
                        pay;

            (2)         any approved sickness, accident, maternity, or 
                        educational leave of an Employee from his duties, 
                        provided the Employee returns to work at the expiry 
                        thereof;

            (3)         any period of Disability during which the Employer is
                        making contributions on behalf of the Employee under
                        Section 4.03; or

            (4)         temporary absence for any reason which does not exceed
                        twenty-six (26) weeks duration, provided the Employee
                        returns to work at the expiry thereof, unless service
                        continuity has been broken in accordance with the
                        Employer's service continuity policy as it may be in
                        effect from time to time.

      Service occurring before a break in Continuous Service shall not
      constitute Continuous Service.

1.06  DISABILITY means the complete inability, as certified in writing by a
      qualified medical practitioner, of a disabled Participant because of
      accidental bodily injury, illness or disease to engage in any occupation
      or employment for remuneration or profit for which he is reasonably suited
      by reason of education, training or experience; provided, however, that a
      disabled Participant shall not be considered to have suffered Disability
      if his state of disablement exists on account of:

            (1)         an accidental bodily injury arising out of or in the
                        course of any employment for
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          remuneration or profit other than with the Employer; 

      (2) accidental bodily injury, illness or disease which is the result of
          war, declared or undeclared; 

      (3) intentionally self-inflicted bodily injury, illness or disease; or 

      (4) accidental bodily injury, illness or disease 

          (a) for which the disabled Participant is not continuously under the
              regular care and attendance of a physician, and 

          (b) if the illness or disease is due to a mental or emotional disorder
              of any type, for which the disabled Participant is not receiving
              continuing treatment from a physician who is certified in
              psychiatry; 

      (5) an illness or a disease due to alcoholism, drug addiction or the use
          of any hallucinogenic or stimulating agent taken voluntarily unless
          the illness or disease is specifically documented as being an organic
          condition.

1.07  EFFECTIVE DATE means 1 January 1989.

1.08  EMPLOYEE means any person employed by the Employer.

1.09  EMPLOYER means the Company and any other company which is a subsidiary or
      affiliate of the Company, and which the Company has designated as a
      participating employer in this Plan.

1.10  EMPLOYER'S FORFEITURE ACCOUNT means the account to which is credited the
      amount in a Participant's Employer Account pursuant to Section 9.01.

1.11  EMPLOYMENT PENSION PLANS ACT means the Employment Pension Plans Act, S.A.
      1986 C.E-10.05 and the Regulations thereunder, as amended or replaced from
      time to time.

1.12  FULL TIME EMPLOYEE means an Employee who is employed on a basis considered
      by the Employer to be a full time permanent basis.

1.13  FUND means all funds at the pertinent time held by the Trustee under the
      Trust Agreement.

1.14  INCOME TAX ACT means the Income Tax Act, S.C. 1970-1971 c. 63 and the
      Regulations thereunder, and where applicable includes the provisions of
      Information Circular 72-13R8 issued by the Department of National Revenue,
      as amended or replaced from time to time.

1.15  INVESTMENT OPTION means any of the pooled investment funds in which the
      Fund may be invested as provided for in the Trust Agreement.

1.16  LOCKED-IN RETIREMENT ACCOUNT means an R.R.S.P. or any registered
      investment account which is eligible for receipt of locked-in retirement
      funds under the Employment Pension Plans Act and the Income Tax Act.


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1.17  MONEY PURCHASE LIMIT for a year means the maximum permissible contribution
      for an individual for that year under the Income Tax Act.

1.18  MONTHLY EARNINGS shall mean a Participant's regular earnings in a month as
      determined from time to time by the Employer, excluding premium pay,
      bonuses, and all payments which are not made on a regular monthly basis.

1.19  NORMAL RETIREMENT DATE means the first day of the month coincident with or
      first following the date on which the Participant attains, or would
      attain, age sixty-five (65).

1.20  PART TIME EMPLOYEE means any Employee who is not a Full Time Employee.

1.21  Participant means any Employee who fulfils the eligibility requirements
      set forth in Section 3 hereof and whose application for participation has
      been accepted and recorded by the Company, and includes a former Employee
      who continues to be entitled to benefits or rights under the Plan.

1.22  PARTICIPANT'S ACCOUNTS means the Participant's Employee Account and the
      Participant's Employer Account.

1.23  PARTICIPANT'S EMPLOYEE ACCOUNT means the account to which contributions
      made by the Participant are credited.

1.24  PARTICIPANT'S EMPLOYER ACCOUNT means the account to which contributions
      made by the Employer in respect of the Participant are credited.

1.25  PARTICIPANT'S VOLUNTARY ACCOUNT means the account to which funds
      transferred from the Prior Plan were allocated under Section 2.02(2)(a),
      and to which contributions made under Section 4.07 are credited.

1.26  PLAN means the Chieftain International, Inc. Retirement Plan established
      hereunder as amended from time to time.

1.27  PLAN YEAR means the calendar year.
 
1.28  PRIOR PLAN means the Chieftain Development Co. Ltd. Executive Retirement
      Plan established effective January 1 1972, and the Chieftain Development
      Co. Ltd. Retirement Plan established effective January 1 1971.

1.29  REGISTERED PENSION PLAN, REGISTERED SAVINGS PLAN and R.R.S.P. bear the
      meaning attributed thereto under the Income Tax Act.

1.30  REMUNERATION means all salary, wages, bonuses, vacation pay, honoraria,
      directors' fees, commissions, taxable allowances, the value of taxable
      benefits, and any other payments for service during the year as an
      Employee of the Employer.
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1.31  RETIREMENT means the commencement of a Participant's pension benefits in
      accordance with Section 6.

1.32  RETIREMENT COMMITTEE means the committee whose appointment, duties, and
      responsibilities are set forth in Section 10 of the Plan.

1.33  SPOUSE means, in relation to a Participant 

      (1) a person of the opposite sex who at the relevant time was married to
          that other person and was not living separate and apart from him, or 

      (2) if there is no person to whom Section 1.33(1) applies, a person of the
          opposite sex who lived with the Participant for the three (3) year 
          period immediately preceding the relevant time and was during
          that period held out by the Participant in the community in which they
          lived as his consort.

1.34  SUPERINTENDENT means the Superintendent of Pensions for the Province of
      Alberta, appointed pursuant to the Employment Pension Plans Act.

1.35  TRUST AGREEMENT means the agreement, including any additional or successor
      agreements, as provided for in Section 11 of the Plan.

1.36  TRUSTEE means the trustee or trustees as specified in the Trust Agreement.

1.37  VALUATION DATE means the date upon which the Trustee causes a valuation to
      be made of the assets held under a particular Investment Option, and gains
      and losses thereunder to be allocated to the beneficial owners, which
      shall occur not less frequently than monthly.

1.38  VESTED RIGHT means the nonforfeitable right of a Participant, or the
      surviving Spouse of a Participant, to a pension benefit under the Plan.

1.39  YEAR'S MAXIMUM PENSIONABLE EARNINGS or YMPE shall have the meaning
      ascribed thereto in the Canada Pension Plan.

1.40  NUMBER AND GENDER

      Whenever used in the Plan, words importing the masculine gender include
      the feminine unless the context requires otherwise. Words importing the
      singular number may be construed to extend to and include the plural and
      vice versa.

1.41  CAPTIONS AND HEADINGS

      Section headings used in this Plan are for convenient reference only and
      shall not be deemed to be a part of the substance of this instrument or in
      any way to enlarge or limit the contents of any Section.
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SECTION 2 - ESTABLISHMENT OF THE PLAN

2.01        This Plan is intended to constitute an employees' pension plan
            qualified for registration under the Employment Pension Plans Act
            and the Income Tax Act. The Company established the Plan effective 1
            January 1989 for the provision of retirement pensions to Employees
            of the Employer subject to 

            (1)         obtaining and retaining such registration of the Plan
                        with the relevant tax authorities as may be necessary to
                        establish that Participants and Employers are entitled
                        to deduct the amount of their contributions from their
                        taxable income under the Income Tax Act as Registered
                        Pension Plan contributions, and 

            (2)         obtaining and retaining such registration of the Plan as
                        may be necessary under the Employment Pension Plans Act.

2.02        (1)         Prior to the Effective Date certain Employees of the
                        Employer were members of the Prior Plan, which was
                        terminated and replaced by this Plan. The value of the
                        benefit of each Participant thereunder was transferred
                        to this Plan, except for any value which was used at the
                        Participant's direction to purchase a deferred life
                        annuity.

            (2)         The amounts transferred from the Prior Plan were
                        allocated to the respective Participants' Accounts, as
                        follows:

                        (a)         any amounts transferred from the Prior Plan
                                    which were "excess contributions" within the
                                    meaning of the Employment Pension Plans Act
                                    were allocated to the respective
                                    Participant's Voluntary Account; and

                        (b)         all other amounts were allocated to the
                                    respective Participant's Employee Account.

2.03        Effective January 1, 1992 the Plan is hereby amended and restated to
            incorporate:

            (1)         changes required under the Employment Pension Plans Act,
                        as amended July 1992; and

            (2)         changes required under the Income Tax Act effective
                        January 1, 1992.

2.04        Unless stated otherwise, the terms of the Plan apply to Participants
            who retire, terminate employment or die on and after January 1, 1992
            and the benefits of Participants who retired, terminated employment,
            or died prior to this date shall be determined by the terms of the
            Plan in effect at the time of that event.

SECTION 3 - PARTICIPATION IN THE PLAN

            3.01        MEMBERS OF PRIOR PLAN
                        Each Employee who was a member of the Prior Plan shall
                        become a Participant of the Plan on the Effective Date.
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3.02        OTHER FULL-TIME EMPLOYEES
            Each other Full Time Employee shall be eligible to participate in
            the Plan on the first day of the month coincident with or first
            following the completion of one (1) year of Continuous Service.
            Participation for each such Full Time Employee shall be compulsory.

3.03        OTHER PART-TIME EMPLOYEES
            Each other Part Time Employee shall be eligible to participate in
            the Plan on the first day of any month coincident with or following
            the 1 January which is first preceded by two (2) consecutive
            calendar years in each of which the Employee's Remuneration was not
            less than thirty-five percent (35%) of the YMPE for such year.
            Participation for each such Part Time Employee shall be voluntary.

3.04        PRIOR MEMBERS OF AEC PLANS
            Any Employee who, immediately prior to his employment with the
            Employer, was employed by Alberta Energy Company Ltd. and was a
            member of any registered pension plan of Alberta Energy Company
            Ltd., shall immediately become a Participant in the Plan on his date
            of employment with the Employer.

3.05        ENROLLMENT
            Each eligible Employee, in becoming a Participant, must sign and
            deliver to the Company a written application for participation on a
            form or forms approved and provided by the Company. Such application
            shall include the agreement by the Employee to be bound by all terms
            of the Plan.

3.06        WRITTEN SUMMARY
            Each Participant and prospective Participant shall receive a written
            explanation of the terms and conditions of the Plan and of any
            amendments thereto which apply to him, together with an explanation
            of the rights and duties with respect to benefits available to him
            under the Plan. A copy of the Plan and of the Trust Agreement shall
            be available at the Head Office of the Company to be read by any
            Participant upon request.

3.07        WITHDRAWAL FROM PLAN PROHIBITED 
            A Participant shall not be allowed to withdraw from the Plan while
            he remains in the employment of the Employer.

3.08        BREAK IN CONTINUOUS SERVICE
            If a Participant has a break in Continuous Service, his
            participation in this Plan, except to the extent that he may have
            acquired a Vested Right, shall cease as of his date of termination
            of service. If such Participant is subsequently re-employed by the
            Employer, he shall be considered for all purposes of the Plan as a
            new Employee and if such Participant had previously acquired a
            Vested Right, such Vested Right shall not be affected by his
            subsequent re-employment with the Employer.
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3.09        WAIVER OF ELIGIBILITY PROVISIONS
            Notwithstanding Sections 3.02 and 3.03, the Company in its sole
            discretion may waive the eligibility requirements in respect of any
            Employee.

3.10        ANNUAL STATEMENT TO PARTICIPANTS
            Each Participant shall receive an annual written statement
            containing the information prescribed under the Employment Pension
            Plans Act in respect of the Participant's benefits under the Plan.

3.11        STATEMENT ON TERMINATION
            A Participant who terminates employment or otherwise ceases to be a
            Participant or any other person who becomes entitled to a benefit
            under the Plan, shall receive a written statement setting out the
            information prescribed under the Employment Pension Plans Act in
            respect of the benefits of the Participant or other person.

SECTION 4 - CONTRIBUTIONS

4.01        PARTICIPANT'S CONTRIBUTIONS
            Each Participant, throughout his participation in the Plan, shall be
            required to contribute monthly to the Fund, through payroll
            deductions, five percent (5%) of his Monthly Earnings, provided that
            a Participant's contributions in any year shall not exceed one-half
            (1/2) of the Money Purchase Limit for that year.

4.02        EMPLOYER'S CONTRIBUTIONS
            The Employer will contribute monthly to the Fund on behalf of each
            Participant an amount equal to such Participant's contributions
            under Section 4.01.

4.03        CONTRIBUTIONS DURING DISABILITY
            The Employer will contribute monthly to the Fund, on behalf of a
            Participant who suffers a Disability, during the period such
            Participant is in receipt of disability benefits from the Employer
            sponsored Long Term Disability Plan. The amount of such contribution
            shall be five percent (5%) of such Participant's Monthly Earnings
            immediately preceding his date of Disability and the amount

            (1)         shall be limited to the amount which the Employer would
                        have otherwise contributed if the Participant had, in
                        the absence of his Disability, continued in active
                        employment with the Employer with no change in his rate
                        of Monthly Earnings, and

            (2)         shall be inclusive of any Employer contribution required
                        under Section 4.02 hereof resulting from Monthly
                        Earnings paid to the Participant during his Disability.

4.04        ADDITIONAL DISCRETIONARY CONTRIBUTIONS
            The Employer may in its absolute discretion make additional
            contributions in respect of the Participants, provided that:

            (1)         the additional contributions must, subject to the
                        following limits, represent a
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RETIREMENT PLAN                                                          PAGE 10
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                        percentage of the Participants' Monthly Earnings which
                        is uniform for all members of a class of Participants,
                        as prescribed under the Employment Pension Plans Act;

            (2)         the total contributions made by the Employer in respect
                        of any Participant in any Plan Year, must not exceed one
                        half (1/2) of the Money Purchase Limit for that year;
                        and

            (3)         the total contributions by or in respect of any
                        individual Participant in any Plan Year shall not exceed
                        eighteen percent (18%) of the Participant's Remuneration
                        for that year.

4.05        USE OF FORFEITURES
            In any month, the Employer may apply all or a portion of the amount
            in the Employer's Forfeiture Account to make Employer Contributions
            under Section 4.02, 4.03 and 4.04, in which case the Employer's
            Forfeiture Account shall be reduced by the amount of such reduction
            in contributions. In any event, any amount in the Employer's
            Forfeiture Account which has not been applied under this Section
            4.05 to reduce the Employer contributions to the Plan by the end of
            the calendar year following the year in which the amount was
            credited to the Employer's Forfeiture Account shall be refunded to
            the Employer at the end of that subsequent year pursuant to Section
            4.06.

4.06        REFUND OF FORFEITURES
            The Employer may, subject to the advance approval of the
            Superintendent, receive a refund of all or a portion of the amount
            in the Employer's Forfeiture Account, in which case the Employer's
            Forfeiture Account shall be reduced by the amount so refunded.

4.07        PARTICIPANT'S ADDITIONAL VOLUNTARY CONTRIBUTIONS
            In addition to his contributions under Section 4.01, a Participant
            may make additional voluntary contributions to the Plan provided
            that the total of all contributions made to the Plan by or in
            respect of the Participant during that year shall not exceed the
            lesser of: 

            (1)         eighteen percent (18%) of the Participant's
                        Remuneration for that year, and 

            (2)         the Money Purchase Limit for the year.

4.08        OTHER CONTRIBUTIONS PROHIBITED
            No contributions shall be permitted to be made to the Plan except as
            provided for in this Section 4.

4.09        REMITTANCE OF CONTRIBUTIONS
            All contributions made by the Participants and the Employer shall be
            transmitted by the Employer for deposit in the Fund within the
            period prescribed under the Employment Pension Plans Act.

4.10        REVERSAL OF ERRONEOUS CONTRIBUTIONS
            Where any person has made a contribution to this Plan, whether in
            error or otherwise, which would cause registration of the Plan under
            the Income Tax Act to be
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            revoked, then such contribution (or such portion thereof as may be
            sufficient to avoid such revocation) shall be returned to the
            contributor, and thereafter the Plan shall be administered as if
            such contribution had never been made. The application of this
            Section 4.10 shall be subject to such notification and documentation
            as the Superintendent may require.

SECTION 5 - ESTABLISHMENT OF ACCOUNTS

5.01        INVESTMENT OPTIONS

            (1)         Upon enrolling in the Plan, each Participant shall file
                        with the Company written instructions as to which of the
                        Investment Options the Participant's Accounts and
                        Participant's Voluntary Account shall be invested in,
                        and in what proportion. Thereafter, the Participant may
                        from time to time file with the Company written
                        instructions changing the Investment Options in which
                        future contributions to the Participant's Accounts and
                        Participant's Voluntary Account shall be invested or
                        directing that transfers be made from one Investment
                        Option to another or both.

            (2)         All such written instructions shall be made on forms
                        provided by the Company for such purposes, and shall be
                        subject to such restrictions as the Company shall
                        establish in consultation with the Trustee.

5.02        ALLOCATION OF CONTRIBUTIONS

            (1)         The Trustee shall maintain records and accounts which
                        reflect the interest of each Participant in the Fund.

            (2)         Required contributions made to the Plan by a Participant
                        under Section 4.01 shall be allocated to the
                        Participant's Employee Account.

            (3)         Contributions made to the Plan by an Employer in respect
                        of a Participant shall be allocated to the Participant's
                        Employer Account.

            (4)         Voluntary contributions made to the Plan by a
                        Participant under Section 4.07 shall be allocated to the
                        Participant's Voluntary Account.

            (5)         Allocations required under this Section 5.02 shall be
                        made forthwith upon receipt by the Trustee of the amount
                        contributed, and the funds invested in accordance with
                        the Participant's instructions under Section 5.01.

5.03        ALLOCATION OF GAINS AND LOSSES
            In respect of each Investment Option and as of each Valuation Date,
            the Trustee shall determine the net income and any realized and
            unrealized gains or losses of that portion of the Fund invested in
            such Investment Option since the last Valuation Date. Such amounts
            shall be allocated, as of the Valuation Date, to the Accounts in the
            proportion that the amount in the individual Account which was
            invested in the particular Investment Option as of the previous
            Valuation Date bears to the aggregate of all such amounts.
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SECTION 6 - RETIREMENT

6.01        NORMAL OR POSTPONED RETIREMENT
            (1)         A Participant may elect Retirement on his Normal
                        Retirement Date, or on the first day of any month
                        thereafter, but not later than the first day of December
                        in the year in which he attains age sixty-nine (69)
            (2)         Where a Participant remains in employment beyond his
                        Normal Retirement Date and elects Retirement while such
                        employment continues, then he shall cease accruing
                        benefits under the Plan as of his date of Retirement.

6.02        EARLY RETIREMENT
            A Participant who has completed two (2) years of Continuous Service
            and whose Continuous Service is terminated on or before his date of
            Retirement, may elect Retirement on the first day of any month prior
            to his Normal Retirement Date, provided that the amount in the
            Participant's Account is sufficient to provide an annual pension
            benefit in the normal form of at least two percent (2%) of the YMPE
            in the year of his Retirement.

6.03        RETIREMENT BENEFIT
            Subject to Section 6.04, the pension benefit payable to a
            Participant on Retirement shall be the amount payable from an
            annuity in the form determined under Section 7 which can be
            purchased by the amount in the Participant's Accounts from any party
            authorized under the laws of Canada or a province to carry on an
            annuities business in Canada. Such a purchase shall serve as a full
            discharge of the Company, the Fund and the Plan with respect to the
            provision of pension benefits under this Plan.

            Notwithstanding the above, a Participant at Retirement may transfer
            the value of his Participant's Accounts to his Locked-In Retirement
            Account or any other prescribed retirement arrangement as permitted
            under the Employment Pension Plans Act.

6.04        COMMUTATION OF SMALL BENEFITS
            If the annual pension benefit payable in the normal form at a
            Participant's Retirement is less than two percent (2%) of the YMPE
            in that year, or if the total value of the Participant's Accounts is
            less than four percent (4%) of the YMPE in that year, then the value
            of the Participant's Accounts shall be paid to the Participant upon
            his Retirement in full and final satisfaction of his benefits under
            the Plan. Such payment shall be made either to the Participant in
            cash, or by way of transfer to his R.R.S.P., as the Participant
            shall direct.

6.05        APPLICATION FOR RETIREMENT
            A Participant must apply in writing, in the form and manner
            prescribed by the Company, prior to any retirement benefit becoming
            payable. Such application must be accompanied by proof of the
            Participant's date of birth and that of his joint annuitant, if
            applicable, and by a declaration of the Participant's marital
            status, both in a form acceptable to the Company.
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6.06        TREATMENT OF PARTICIPANT'S VOLUNTARY ACCOUNT
            Upon the retirement of a Participant, the Participant shall elect
            that the value of his Participant's Voluntary Account shall be paid
            to him in cash, transferred to his R.R.S.P. or included within his
            Participant's Accounts, and used to provide a benefit in accordance
            with this Plan. Failing such election the Participant shall be
            conclusively deemed to have elected to receive the benefit in cash.

SECTION 7 - FORMS OF RETIREMENT BENEFITS

7.01        NORMAL FORM
            The normal form of retirement benefit (hereinafter referred to as
            the "normal form") shall be payable in equal monthly installments,
            due on the last day of each month, for the life of the Participant,
            with the first payment due for the month in which Retirement
            occurred. Upon the death of the retired Participant, benefits in the
            normal form shall be payable: 

            (1)         if the Participant has a Spouse at Retirement, and that
                        Spouse survives him, to the Spouse for the life of the
                        Spouse in equal monthly installments of an amount equal
                        to sixty percent (60%) of the monthly amount payable to
                        the Participant during his lifetime; or 

            (2)         if the Participant does not have a Spouse at Retirement,
                        and the Participant dies prior to having received one
                        hundred and twenty (120) monthly payments, the balance
                        of the one hundred and twenty (120) monthly payments
                        shall be payable to the Beneficiary or estate of the
                        Participant.

7.02        OPTIONAL FORMS
            Subject to Sections 7.03 and 7.04, a Participant may elect an
            optional form of retirement benefit provided that: 

            (1)         the Company agrees to such option, and 

            (2)         such option provides for at least the payment of
                        retirement benefits during the Participant's lifetime,
                        and 

            (3)         such other option is permissible under the Income Tax
                        Act and the Employment Pension Plans Act.

7.03        ELECTION OF OPTIONAL FORMS
            A Participant who wishes his retirement benefit to be paid in an
            optional form pursuant to Section 7.02 must submit his written
            election to the Company at least thirty (30) days prior to his date
            of Retirement in a form acceptable to the Company. An election under
            Section 7.02 may be revoked by the Participant, provided written
            notice of such revocation is received by the Company at least thirty
            (30) days prior to his date of Retirement. Should the Participant's
            joint annuitant die before the commencement of retirement benefits,
            the Participant's election of the joint and survivor annuity
            optional form shall be void and his retirement benefits shall be
            paid in accordance with Section 7.01.
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7.04        RESTRICTION FOR MARRIED PARTICIPANTS
            Notwithstanding Section 7.02 and 7.03, a Participant who has a
            Spouse at Retirement shall not be entitled to elect an optional form
            of benefit under Section 7.02 if such form provides the Spouse with
            a survivor benefit of less than sixty percent of the monthly amount
            payable to the Participant, unless the Participant's Spouse has
            filed with the Company a statement of waiver in the form and manner
            required under the Employment Pension Plans Act.

7.05        BENEFITS CEASING ON DEATH
            The portion of any benefit which is payable for the lifetime of any
            person shall cease with the last payment due on the last day of the
            month preceding the month in which such person's death occurs.

SECTION 8 - DEATH PRIOR TO RETIREMENT

8.01        DEATH WITH SPOUSE AS SURVIVOR

            (1)         If the Participant dies prior to Retirement and is
                        survived by his Spouse, the combined value of the
                        Participant's Accounts shall be payable for the benefit
                        of his Spouse. The Spouse shall elect that the benefit
                        shall be transferred to the Spouse's Locked-in
                        Retirement Account, or paid as a pension for life under
                        Section 8.03.
            (2)         If the combined value of the Participant's Accounts is
                        less than four percent (4%) of the YMPE or the annual
                        pension benefit payable to the surviving Spouse in the
                        normal form at the Spouse's Normal Retirement Date,
                        interpreted as if the Spouse were a Participant, would
                        be less than two percent (2%) of the YMPE, each measured
                        as of the year of the Participant's death, the benefit
                        may be paid to the Spouse in cash, or transferred to his
                        R.R.S.P.

8.02        DEATH WITHOUT A SPOUSE
            If a Participant dies prior to Retirement and is not survived by his
            Spouse, the value of the Participant's Accounts shall be payable to
            his Beneficiary. The benefit shall be paid in cash unless the
            Beneficiary, if eligible under the Income Tax Act, elects, within
            ninety (90) days of being informed of his entitlements under the
            Plan, that the benefit be transferred to his R.R.S.P.

8.03        BENEFITS FOR SURVIVING SPOUSE
            The benefit payable to the Spouse under Section 8.01 shall be
            determined in accordance with Sections 8.04 through 8.07 below.

8.04        ELECTION OF BENEFIT FOR LIFE
            The Spouse may elect to receive the benefit payable under Section
            8.01 in the form of a pension for life, provided that the resulting
            annual pension amount is not less than two percent (2%) of the YMPE
            in the year of the Participant's death. Such election must be
            accompanied by proof acceptable to the Company of the Spouse's date
            of birth, and must be filed with the Company not later than ninety
            (90) days after
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RETIREMENT PLAN                                                          PAGE 15
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            his having been informed of his entitlements under the Plan.

8.05        GUARANTEED PERIOD
            The Spouse may elect the pension for life under Section 8.04 with or
            without a guaranteed period; provided that the guaranteed period
            shall not exceed fifteen (15) years.

8.06        PENSION IN EQUAL MONTHLY INSTALLMENTS
            The Spouse's pension for life shall be payable in equal monthly
            installments payable on the last day of each month, with the first
            such payment being made as soon as practicable after the
            Participant's death, in the amount that is payable from an annuity
            purchased pursuant to Section 8.07 with the value of the
            Participant's Accounts.

8.07        PURCHASE OF ANNUITY
            The Fund shall provide for the payment of the pension for life by
            the purchase of a life annuity from any party authorized by the laws
            of Canada or a province to carry on an annuities business in Canada.
            The purchase of such annuity by the Fund shall serve as a full
            discharge of the obligations of the Company, the Fund, and the Plan
            with respect to the provision of benefits to the surviving Spouse.

8.08        DISTRIBUTION OF PARTICIPANT'S VOLUNTARY ACCOUNT
            If a Participant dies prior to Retirement, his Spouse or, if there
            is no Spouse, his Beneficiary, shall elect that the value of the
            Participant's Voluntary Account shall be paid to him in cash,
            transferred to his R.R.S.P. or included with the Participant's
            Accounts, and used to provide a benefit in accordance with this
            Plan. Failing such election, the Spouse shall be conclusively deemed
            to have elected the cash payment.

8.09        DESIGNATION OF BENEFICIARY
            A Participant may designate a Beneficiary to receive the benefits
            payable under the Plan in the event of the Participant's death, and
            may also by written notice, given to the Company during such
            Participant's lifetime, alter or revoke such designation from time
            to time, subject to any applicable law. Any designation or written
            notice shall be in such form and executed in such manner as the
            Company may require.

8.10        DESIGNATION BY SURVIVING SPOUSE
            If a Spouse is entitled to receive a benefit under this Section 8,
            then such Spouse shall have the same rights as those ascribed to a
            Participant in Section 8.09 in respect of benefits payable after
            such Spouse's death.

8.11        FAILURE OF BENEFICIARY
            If at the death of a Participant the person designated as the
            Beneficiary shall not then be living or if no person has been
            designated by the Participant, such amount as may be payable on or
            after the Participant's death shall be paid to the estate of the
            Participant.
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CHIEFTAIN INTERNATIONAL, INC.
RETIREMENT PLAN                                                          PAGE 16
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8.12        DOCUMENTATION OF CLAIM
            The Company may require the execution or delivery of such documents
            as it may deem appropriate to be assured that the payment of death
            payments is properly made and is made to the proper party entitled
            thereto.

8.13        PAYMENT OF LUMP SUM IN LIEU OF PERIODIC BENEFITS
            Notwithstanding anything in this Plan to the contrary, if any
            benefits would, in the absence of this provision, be payable to an
            estate as a series of monthly or other periodic payments, the
            actuarial present value thereof shall be paid to such estate in a
            lump sum in lieu thereof.

8.14        BENEFITS ON DEATH OF BENEFICIARY
            If, as a result of a Participant's death, a Beneficiary is entitled
            to payments under the Plan, and if the Beneficiary dies before
            receiving any or all payments to him, the remainder of the payments
            will be paid in a lump sum to the estate of the Beneficiary.

8.15        DEATH BENEFIT TO SPOUSE'S BENEFICIARY
            If the Participant should predecease his Spouse and the Spouse dies
            without having elected or become entitled to make the transfers
            under Section 8.01, an amount equal to the sum of the Participant's
            Accounts plus the Participant's Voluntary Account, if any, shall be
            payable to the Spouse's designated beneficiary or if there is no
            such person living, the Spouse's estate.

8.16        DEATH BENEFITS FOLLOWING RETIREMENT
            Any death benefit payable upon the death of a Participant who has
            commenced to receive his pension shall be determined in accordance
            with the form of the pension being paid to the Participant pursuant
            to Section 7.

SECTION 9 - TERMINATION OF SERVICE

9.01        TERMINATION PRIOR TO VESTING
            If the Continuous Service of a Participant terminates, for any
            reason other than death, prior to his electing Retirement and prior
            to his having completed two (2) years of Continuous Service, he will
            receive the value in his Participant's Employee Account, either in
            cash or by way of transfer to his R.R.S.P., as the Participant may
            elect. If the Participant does not make an election within ninety
            (90) days of being informed of his entitlements under the Plan (or
            his date of termination, if later), the benefit shall be paid in
            cash. The value of the Participant's Employer Account shall be
            forfeited and credited to the Employer's Forfeiture Account.

9.02        TERMINATION SUBSEQUENT TO VESTING
            If the Continuous Service of a Participant terminates, for any
            reason other than death, prior to his electing Retirement but after
            his having completed two (2) years of Continuous Service, he shall
            be entitled to elect either:

            (1)         to transfer the value of his Participant's Accounts to
                        his Locked-In Retirement Account; or
<PAGE>   17
CHIEFTAIN INTERNATIONAL, INC.
RETIREMENT PLAN                                                          PAGE 17
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            (2)         subject to Section 9.04, to leave his Participant's
                        Accounts in the Fund and receive a pension benefit upon
                        Retirement, in accordance with Section 6.

9.03        DISCRETION TO WAIVE VESTING PERIOD
            Notwithstanding Section 9.01, if the Continuous Service of a
            Participant shall terminate prior to his having completed at least
            two (2) years of Continuous Service, the Company, in its sole and
            absolute discretion, may deem that the Plan shall be interpreted as
            if that Participant had completed two (2) years of Continuous
            Service.

9.04        MANDATORY TRANSFER OF SMALL BENEFITS
            If the value of the Participant's Accounts is less than ten percent
            (10%) of the YMPE in the year the Participant's employment
            terminates, the Company may require the Participant to make the
            transfer provided for in Section 9.02(1).

9.05        COMMUTATION OF SMALL BENEFITS
            If the annual pension benefit payable in the normal form at a
            Participant's termination is less than two percent (2%) of the YMPE
            in that year, or if the total value of the Participant's Accounts is
            less than four percent (4%) of the YMPE in that year, then the value
            of the Participant's Accounts shall be paid to the Participant upon
            his termination in full and final satisfaction of his benefits under
            the Plan. Such payment shall be made either to the Participant in
            cash, or by way of transfer to his R.R.P. as the Participant shall
            direct.

9.06        TIME LIMIT FOR ELECTIONS
            The election referred to in Section 9.02 must be made by the
            Participant in writing no later than ninety (90) days after having
            been informed of his entitlements under the Plan (or his termination
            of Continuous Service, if later). If no such election is filed with
            the Company within the prescribed period, the Participant shall be
            deemed to have elected the option provided in Section 9.02(2). The
            Company may, however, in its discretion, extend the time limits for
            the filing of such election.

9.07        DISTRIBUTION OF PARTICIPANT'S VOLUNTARY ACCOUNT
            Upon the termination of a Participant's Continuous Service, for any
            reason other than death, prior to his electing Retirement, the
            Participant shall elect that the value of his Participant's
            Voluntary Account shall be paid to him in cash, transferred to his
            R.R.S.P. or included with his Participant's Accounts, and used to
            provide a benefit in accordance with this Plan. Failing such
            election the Participant shall be conclusively deemed to have
            elected to receive the benefit in cash.

SECTION 10 -ADMINISTRATION OF THE PLAN

10.01       COMPANY RESPONSIBLE FOR PLAN
            While the Plan remains in force the Company shall have the sole
            responsibility for and the sole control of its operation and
            administration, and shall have the power and duty to take all action
            and to make all decisions and interpretations which shall be
            necessary or appropriate in order to administer and carry out the
            Plan including the
<PAGE>   18
CHIEFTAIN INTERNATIONAL, INC.
RETIREMENT PLAN                                                          PAGE 18
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            power to make and enforce such rules and regulations as it shall
            deem necessary. The Company may however delegate all or a portion of
            its duties pursuant to the administration of the Plan to a
            Retirement Committee consisting of not less than two (2) members to
            be appointed by and serving at the pleasure of the Company. The
            majority of such members must be residents in Canada. The Company
            shall fill all vacancies on the Committee occurring by death or
            resignation or removal of members thereof. The Company may from time
            to time remove any member of the Committee with or without cause,
            and shall appoint a successor. Any member of the Retirement
            Committee may resign at any time. Any expenses properly incurred by
            the Retirement Committee or any member thereof shall be reimbursed
            from the Fund unless paid by the Company.

10.02       RETENTION OF PROFESSIONALS
            The Company or the Retirement Committee may from time to time retain
            such independent counsel, accountants, actuaries, and other parties
            or advisors (hereinafter referred to as "Professionals") as it may
            require in carrying out its responsibilities referred to under
            Section 10.01. Upon direction of the Company, the fees and expenses
            of such Professionals, to the extent that they may be reasonably
            associated with the operation and administration of the Plan, shall
            be paid from the Fund unless paid by the Company.

SECTION 11 - RETIREMENT TRUST FUND

11.01       COMPANY TO ENTER TRUST AGREEMENT
            The Company shall enter into a Trust Agreement with the Trustees who
            shall be appointed by the Company. The contributions of the Employer
            under this Plan will be received, held, invested, and administered
            as a Trust Fund in accordance with the terms of the Trust Agreement,
            the Plan, the Income Tax Act, and the Employment Pension Plans Act
            in order to provide for the payment of benefits in accordance with
            the Plan. The Company may remove any or all Trustees at any time
            upon reasonable notice, and, upon such removal or upon resignation
            of any or all of the Trustees, the Company shall appoint successor
            Trustees.

11.02       FISCAL YEAR OF FUND
            The fiscal year of the Fund shall be the calendar year.

11.03       LOANS FROM PLAN PROHIBITED
            The Plan will not permit loan privileges to any Participant.

SECTION 12 - AMENDMENT OR TERMINATION OF THE PLAN

12.01       RIGHT TO AMEND OR TERMINATE RESERVED
            The Company retains the right to amend or terminate the Plan in
            whole or in part at any time and from time to time and in such
            manner and to such extent as it may deem advisable, provided that:

            (1)         no amendment shall have the effect of reducing the then
                        existing value of any
<PAGE>   19
CHIEFTAIN INTERNATIONAL, INC.
RETIREMENT PLAN                                                          PAGE 19
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                        Participant's Account, except by the provision of
                        benefits of equal value;

            (2)         each amendment to the Plan shall be in writing and shall
                        be executed and acknowledged on behalf of the Company by
                        its President or a Senior Vice President and attested to
                        by its Corporate Secretary or an Assistant Corporate
                        Secretary and sealed with its Corporate Seal; and

            (3)         termination of the Plan shall be accomplished only by
                        appropriate resolution of the Company, and a copy of
                        such resolution shall be provided to all affected
                        Participants.

12.02       AUTOMATIC VESTING ON PLAN TERMINATION
            (1) Upon termination of the Plan, in whole or in part, each affected
            Participant shall be deemed to have terminated his service with the
            Employer on the date of Plan's termination and to have completed at
            least two (2) years of Continuous Service, and his entitlements
            shall be determined in accordance with Section 9.02.

            (2) If the Plan is terminated, the Trustees and the Retirement
            Committee shall continue to function as such for such period of time
            as may be necessary for the winding up of the Plan.

SECTION 13 -GENERAL CONDITIONS

13.01       PLAN NOT A CONTRACT OF EMPLOYMENT
            The adoption and maintenance of the Plan shall not be deemed to
            constitute a contract of employment between the Employer and any
            Employee or Participant. Nothing contained herein shall be deemed to
            give to any Employee the right to be retained in the service of the
            Employer or to interfere with the right of the Employer to terminate
            the service of any Employee or Participant at any time.

13.02       BENEFITS INALIENABLE

            (1)         All payments made to a Participant, Beneficiary, Spouse,
                        or a joint annuitant pursuant to the Plan are for the
                        support and maintenance of such Participant,
                        Beneficiary, Spouse, or joint annuitant and may not be
                        assigned, alienated, sold, transferred, pledged,
                        encumbered, anticipated, charged, surrendered, or given
                        as security and to the extent permitted by law shall not
                        be subject to attachment or otherwise to the claims of
                        creditors of the Participant, Beneficiary, Spouse, or
                        joint annuitant.

            (2)         Subject to the Employment Pension Plans Act, the
                        entitlement of any person to receive a benefit under
                        this Plan is subject to entitlements arising under a
                        matrimonial property order, within the meaning of the
                        Matrimonial Property Act, or a similar order enforceable
                        in Alberta.

13.03       TIME LIMIT FOR TRANSFERS
            If a person becomes entitled to receive benefits under the Plan, the
            payment shall be made within sixty (60) days after the event giving
            rise to the payment or the completion and filing of all documents
            required to authorize the making of the payment.
<PAGE>   20
CHIEFTAIN INTERNATIONAL, INC.
RETIREMENT PLAN                                                          PAGE 20
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13.04       LIMITATION OF LIABILITY
            Neither the Company, any Employer, the Trustees, nor any individual
            or committee selected by the Company to perform services or render
            advice in connection with this Plan, shall be liable to anyone in
            connection with the Plan except for his own gross neglect or willful
            misconduct, and no committee member shall be liable for the act or
            omission of any other committee member.

13.05       SEVERABILITY
            If any provision of this Plan is held to be invalid or unenforceable
            by a court of competent jurisdiction, its invalidity or
            unenforceability shall not affect any other provision of the Plan
            and the Plan shall be construed and enforced as if such provision
            had not been included therein.

13.06       PLAN TEXT PREVAILS OVER TRUST AGREEMENT
            Any provision of the Trust Agreement that is inconsistent with the
            terms of the Plan shall, to the extent of the inconsistency, be of
            no force or effect.

13.07       PLAN UNDER ALBERTA LAW
            This Plan shall be governed and construed in accordance with the law
            of the Province of Alberta.