Second Amendment to Geodyne
         Institutional/Pension Energy Income Limited Partnership P-6
            Amended and Restated Agreement of Limited Partnership


     This  Second  Amendment  to  Geodyne  Institutional/Pension  Energy  Income
Limited  Partnership P-6 (the  "Partnership")  Amended and Restated Agreement of
Limited  Partnership  is entered into by and between  Geodyne  Properties,  Inc.
("Properties"),   a   Delaware   corporation,   as  General   Partner,   Geodyne
Institutional Depositary Company ("Depositary"),  a Delaware corporation, as the
Limited  Partner,   and  all  Substituted   Limited  Partners  admitted  to  the
Partnership.


     WHEREAS,  on November  28, 1989,  Properties  and  Depositary  executed and
entered  into  that  certain  PaineWebber/Geodyne  Institutional/Pension  Energy
Income  Limited   Partnership   P-6  Agreement  of  Limited   Partnership   (the
"Agreement"); and


     WHEREAS,  on  September 5, 1990,  Properties  and  Depositary  executed and
entered  into  that  certain  PaineWebber/Geodyne  Institutional/Pension  Energy
Income  Limited  Partnership  P-6  Amended  and  Restated  Agreement  of Limited
Partnership (the "Amended and Restated Agreement"); and


     WHEREAS,  on February 25, 1993,  Properties  executed and entered into that
certain  First  Amendment  to said  Amended and  Restated  Agreement  whereby it
changed   (i)   the   name   of  the   Partnership   from   "PaineWebber/Geodyne
Institutional/Pension   Energy  Income  Limited  Partnership  P-6"  to  "Geodyne
Institutional/Pension  Energy Income Limited  Partnership P-6", (ii) the address
of the Partnership's  principal place of business, and (iii) the address for the
Partnership's agent for service of process; and


     WHEREAS,  Section 11.1 of the Amended and Restated  Agreement provides that
the General  Partner  may,  without  prior notice or consent of any Unit Holder,
amend any provision of this  Agreement if, in its opinion,  such  amendment does
not have a material adverse effect upon the Unit Holders; and


     WHEREAS,  Properties  as General  Partner  desires to amend the Amended and
Restated Agreement in order to (i) expedite the method of accepting transfers of
Unit Holders' Units in the Partnership and (ii) provide for an optional right of
repurchase/redemption which may be exercised by the Unit Holders.

     NOW,  THEREFORE,   in  consideration  of  the  covenants,   conditions  and
agreements herein contained, the parties hereto hereby agree as follows:



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I.     The third sentence  contained in Section 7.3 of the Agreement is hereby
       amended and restated as follows:

            Unit Holders becoming  Substituted Limited Partners will be admitted
            to the Limited Partnership monthly.


II.    The second  sentence  contained  in Section 7.3 of the  Agreement,  which
       sentence  required  the  payment by Unit  Holders of a fee (not to exceed
       $100) for legal and administrative  costs associated with the transfer of
       a Limited Partnership Unit, is hereby deleted.


III.   The first  sentence  contained  in  Section 8.1E  of the  Agreement  is
       hereby amended and restated as follows:

            Unless  otherwise  provided  by  the  General  Partner,   any  sale,
            assignment or transfer of a Substituted  Limited Partner's  Interest
            shall be  recognized  by the  Limited  Partnership  as of the  first
            business day of the month  following the approval of such assignment
            or transfer by the General Partner.


IV.    The  second  sentence  contained  in  Section  8.1E  of  the  Agreement
       referring to quarterly approvals of transfers is hereby deleted.


V.     Section 8.2B(iii) of the Agreement, which section required the payment of
       a fee  (not to  exceed  $50) for  expenses  associated  with the  General
       Partner's acceptance of a Substituted Limited Partner is hereby deleted.


VI.    Section 8.2(D)  of the  Agreement  is hereby  amended  and  restated as
       follows:

            The General  Partner  shall amend the  Agreement  at least once each
            month if necessary to effect the substitution of Substituted Limited
            Partners.


VII.   The last sentence of Section  8.3(A) of the Agreement is hereby amended
       to reflect the deletion of the reference to a transfer fee.


VIII.The Agreement is hereby amended to provide for a new Article Fifteen.  Said
       Article Fifteen is hereby stated as follows:




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                                 Article Fifteen

                   Optional Repurchase/Redemption Provisions

            Section 15.1.  Optional Repurchase Right.

            Any Unit Holder or Substituted Limited Partner shall have the right,
      at his  option,  to  present  his  Units  to the  General  Partner  or its
      designated Affiliate for repurchase on the basis set forth in this Article
      Fifteen.

                Section 15.2.  Procedure for Repurchase.

            A. As of December 31, 1992 and annually  thereafter  (the "Appraisal
      Date") the General  Partner shall  appraise the Proved  Reserves and other
      assets of the Partnership  pursuant to the provisions set forth herein and
      shall  assign a  repurchase  price  (the  "Repurchase  Price") to the Unit
      Holders' Units in the  Partnership  in accordance  with the provisions set
      forth herein.

            B. In  arriving  at the  Repurchase  Price,  the  General  Partner
      shall consider those factors  deemed  relevant by it including,  without
      limitation, the following:

            (i)        the present  value of the  estimated  future
                       net   revenues  of  the  NPI   Partnership's
                       Proved  Reserves,  calculated  as  described
                       below; and

            (ii)       the  book  value  of all  other  Partnership
                       assets and liabilities.

            Section 15.3.  Calculation  of Present Value of the  Partnership's
      Estimated Future Net Revenues.

            In  calculating  the present  value of the  Partnership's  Estimated
      Future  Net  Revenues  the  General   Partner   shall  use  the  petroleum
      engineering reports and other petroleum reserve information required to be
      furnished to the Unit Holders pursuant to Section 10.4C of the Agreement.

            Future gross revenues expected to be derived from the production and
      sale of the Proved  Reserves  attributable  to the NPI  Partnership's  Net
      Profits  Interests  and  Royalties  shall be  estimated  using  either (i)
      escalations of future sales prices of Hydrocarbons supplied by the General
      Partner  (the  "Escalated  Case") or (ii)  sales  prices  of  Hydrocarbons
      provided  by  Regulation  S-X  adopted  by  the  Securities  and  Exchange
      Commission  (the "SEC Case"),  as the General Partner may determine in its
      sole discretion.

            Future net revenues  shall be  calculated  by deducting  anticipated
      expenses  (using either (i)  escalations  of future costs  supplied by the
      General  Partner if the General  Partner  adopted the Escalated  Case with
      respect to future sales prices of  Hydrocarbons  or (ii)  constant  future
      costs if the General  Partner  adopted the SEC Case with respect to future
      sales prices of Hydrocarbons) from estimated future gross revenues.



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            The present value of the future net revenues  shall be calculated by
      discounting  the  estimated  future  net  revenues  at either  10% (if the
      General Partner  employed  future pricing  criteria in accordance with the
      SEC Case) or that rate per annum which is one percentage point higher than
      the prime  rate of  interest  of The Chase  Manhattan  Bank,  N.A.  or any
      successor bank, as of the Appraisal Date (if the General Partner  employed
      pricing criteria in accordance with the Escalated Case, provided, however,
      that such  discount rate will not exceed 18% per annum and will be no less
      than 10% per annum).

            Section 15.4.  Risk Reduction.

            In  determining  the Repurchase  Price for Unit Holders  pursuant to
      this  Article  Fifteen,  the  present  value of the  Partnership's  Proved
      Developed  Producing  Reserves  shall be  reduced  by 25% for risk and the
      present value of all other  categories of Proved Reserves shall be reduced
      by 35% for  risk.  The risk  reductions  shall be  subject  to  upward  or
      downward  adjustment by the General  Partner if, during the period between
      the Appraisal  Date and the Effective  Date (as defined in Section  15.5),
      there has been a material increase or decrease in the current price of oil
      or gas or in the estimated amount of the Partnership's Proved Reserves.

            Section 15.5.  Tender Procedure.

            Upon completion of the appraisal of the  Partnership's  assets as of
      the Appraisal  Date, the General  Partner shall notify each Unit Holder of
      the Repurchase  Price and his  proportionate  share thereof and either the
      General  Partner or one of its Affiliates will offer to purchase such Unit
      Holder's Units in exchange for such Unit Holder's  proportionate  share of
      the Repurchase Price (a "Repurchase  Offer").  Any Unit Holder desiring to
      do so may accept such Repurchase Offer by notifying the General Partner of
      his  election.  Unit Holders so  notifying  the General  Partner  shall be
      referred to herein as "Electing Unit Holders".  The General Partner or its
      designated  Affiliate shall  thereupon  promptly pay to each Electing Unit
      Holder, his proper share of the Repurchase Price, calculated as herein set
      forth,  within 30 days from the date which a properly drawn  assignment of
      such  Electing  Unit  Holder's  interest,  free and clear of all liens and
      encumbrances,  is tendered to and  accepted by the General  Partner or its
      designated  Affiliate (the "Effective  Date").  Upon the acquisition of an
      Electing  Unit  Holder's  Units,  the  General  Partner or its  designated
      Affiliate shall, as of the Effective Date of such acquisition,  succeed to
      all the rights and obligations attributable to such interest.



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            Section   15.6.   Monthly   Adjustment   to  Repurchase
      Price.

            The  Repurchase  Price  shall  be  recalculated   monthly  with  the
      Repurchase Price being reduced by the amount of any cash  distributions to
      Unit Holders  during the period from the Appraisal Date to the date of the
      payment of the Repurchase Price and shall otherwise be adjusted to reflect
      the effect of material operations during such period, including a material
      increase  or  decrease  in  the  current  price  of  oil  or gas or in the
      estimated amount of the  Partnership's  Proved Reserves.  In the event the
      Repurchase  Price is  adjusted  for any reason  other than to reflect  the
      payment of cash  distributions,  the General Partner shall provide written
      notification  of such  adjustment  to the Unit  Holders  at least ten (10)
      business days prior to acceptance of Units for purchase.

            Section 15.7.  Limitation on Units Repurchased.

            A. At the  sole  discretion  of the  General  Partner,  the  General
      Partner or its  designated  Affiliate may either (i) limit the time period
      in which it will accept  tendered  Units for  repurchase or (ii) limit the
      amount of Units to be accepted for repurchase;  provided, however, that in
      any event the annual  repurchase  offer will (i) remain  open for at least
      thirty (30) days and (ii) the General Partner or its designated  Affiliate
      will offer to annually  repurchase  (and will purchase  validly  presented
      Units) at least 10% of the outstanding  Units of the  Partnership.  In the
      event  the  General  Partner  or  its  designated   Affiliate   imposes  a
      limitation, the General Partner will either (i) specify such limitation(s)
      in the annual  Repurchase Offer mailed to the Unit Holders or (ii) provide
      all Unit Holders with written  notification of such limitation(s) at least
      thirty (30) days prior to the effective date of any such limitation(s).

            B. In the event the General  Partner  imposes a limitation  upon the
      number of Units to be  repurchased in the  Partnership,  and the amount of
      Units  tendered,  but  not  repurchased,  exceeds  such  limitation,  such
      tendered Units will be accepted for repurchase by lot.

            C. In  addition,  in order to avoid  certain  possible  adverse  tax
      consequences,  the  General  Partner  may,  in  order to  comply  with the
      regulations  or procedures  under Section  469(k) of the Internal  Revenue
      Code of 1986, as amended,  relating to "publicly traded partnerships," (i)
      delay or defer the  Effective  Date of any  repurchase  and (ii) limit the
      total number of Units of any Partnership to be repurchased in any 12-month
      period to the maximum number provided in such  regulations and procedures.
      In the event of such delay or deferral,  the General  Partner shall notify
      the Electing  Unit Holder of the reasons  therefor  and shall  provide the
      Electing  Unit Holder with the option to withdraw  his tender of Units for
      repurchase.




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<PAGE>




       IN WITNESS  WHEREOF,  the parties hereto have hereunto set their hands as
of the 4th day of August, 1993.

                                       Geodyne Properties, Inc.
                                       as General Partner


                                       By:  /s/ C. Philip Tholen
                                            ----------------------------
                                            C. Philip Tholen
                                            President


                                       Geodyne Institutional Depositary
                                       Company, as the Limited Partner



                                       By:  /s/ Dennis R. Neill
                                            ----------------------------
                                            Dennis R. Neill
                                            Senior Vice President



                                       Geodyne Properties, Inc., as
                                       Attorney-in-Fact for all Substituted
                                       Limited Partners



                                       By:  /s/ Drew S. Phillips
                                            ----------------------------
                                            Drew S. Phillips
                                            Vice President - Controller


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