Document:

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                                                                   EXHIBIT 10.53

                         AMENDMENT TO WARRANT AGREEMENT

         THIS AMENDMENT TO WARRANT AGREEMENT ("Amendment") is made as of
December 6, 2001, between SOMANETICS CORPORATION, a Michigan Corporation (the
"Company"), and BREAN MURRAY & CO., INC. (the "Representative").

                                    RECITALS

         A. The Company and the Representative entered into a Warrant Agreement,
dated as of April 9, 2001 (the "Agreement"), pursuant to which the Company
issued a Warrant (the "Warrant") to purchase 25,000 of its Common Shares, par
value $0.01 per share ("Common Shares"), at $2.10 a share to the Representative.

         B. The Company and the Representative desire to amend the Agreement, to
restate the provisions that protect against certain dilutive events.

         THEREFORE, the Company and the Representative agree as follows:

         1. INTRODUCTORY PARAGRAPH. The last two sentences of the introductory
paragraph of the Agreement are amended and restated to read as follows: "The
Aggregate Warrant Price is not subject to adjustment, except as otherwise
provided in subsection III(j). The Per Share Warrant Price and the number of
Warrant Shares are subject to adjustment as hereinafter provided."

         2. AMENDMENT TO DILUTIVE EVENTS PROVISION. Section III of the Agreement
is amended and restated to read as follows:

         "III.    Adjustments of Exercise Price and Number of Shares. The Per
                  Share Warrant Price and the number and kind of securities
                  issuable upon exercise of this Warrant shall be subject to
                  adjustment from time to time upon the happening of certain
                  events, as follows:"

                  "A.      If the Company (i) declares a dividend on its Common
                           Stock in Common Stock or makes a distribution to all
                           holders of its Common Stock in Common Stock without
                           charge to such holders, (ii) subdivides its
                           outstanding Common Stock, (iii) combines its
                           outstanding Common Stock into a smaller number of
                           shares of Common Stock or (iv) issues by
                           reclassification of its Common Stock other securities
                           of the Company (including any such reclassification
                           in connection with a consolidation or merger in which
                           the Company is the surviving entity, but excluding
                           those referred to in paragraph (b) below), the number
                           and kind of shares of Common Stock purchasable upon
                           exercise of this Warrant immediately prior thereto
                           shall be adjusted so that the Holder of this Warrant
                           shall be entitled to receive the kind and number of
                           shares of Common Stock or other securities of the
                           Company which such Holder would have owned or have
                           been entitled to receive

<PAGE>
                  after the happening of any of the events described above, had
                  such Warrant been exercised immediately prior to the happening
                  of such event or any record date with respect thereto. Such
                  adjustment shall be made whenever any of the events listed
                  above shall occur. An adjustment made pursuant to this
                  paragraph (a) shall become effective immediately after the
                  effective date of such event retroactive to immediately after
                  the record date, if any, for such event."

         "B.      If the Company issues rights, options or warrants to all
                  holders of its Common Stock, without any charge to such
                  holders, entitling them to subscribe for or to purchase Common
                  Stock at a price per share lower than the then current Market
                  Price per share of Common Stock at the record date mentioned
                  below (as defined in paragraph (d) below), the Holders of
                  unexercised Warrants as of such record date, upon exercise of
                  such Warrants, shall receive the same rights, options or
                  warrants which such Holder would have received or have been
                  entitled to receive after such issuance, had such Warrants
                  been exercised immediately prior to such issuance or any
                  record date with respect thereto. Such adjustment shall be
                  made whenever such rights, options or warrants are issued as
                  described above, and shall become effective retroactively to
                  immediately after the record date for the determination of
                  shareholders entitled to receive such rights, options or
                  warrants."

         "C.      If the Company distributes to all holders of its Common Stock,
                  without any charge to such holders, shares of its stock other
                  than Common Stock or evidences of its indebtedness or assets
                  (excluding cash dividends and dividends or distributions
                  referred to in paragraph (a) or (b) above) or rights, options
                  or warrants or convertible or exchangeable securities
                  containing the right to subscribe for or purchase Common Stock
                  (excluding those referred to in paragraph (a) or (b) above),
                  then in each case the Holders of unexercised Warrants as of
                  the record date mentioned below, upon exercise of such
                  warrants, shall receive the same distribution which such
                  Holder would have received or have been entitled to receive
                  after such distribution, had such Warrants been exercised
                  immediately prior to such distribution or any record date with
                  respect thereto. Such adjustment shall be made whenever any
                  such distribution is made as described above, and shall become
                  effective on the date of distribution retroactive to
                  immediately after the record date for the determination of
                  shareholders entitled to receive such distribution."

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<PAGE>

         "D.      For the purpose of any computation under paragraph (b) of this
                  Section III, the current "Market Price" per share of Common
                  Stock at any date shall be the average of the daily closing
                  prices for fifteen (15) consecutive trading days commencing
                  twenty (20) trading days before the date of such computation.
                  The closing price for each day shall be the last reported sale
                  price regular way or, in case no such reported sale takes
                  place on such day, the average of the closing bid and asked
                  prices regular way for such day, in either case on the
                  principal national securities exchange on which the shares are
                  listed or admitted to trading, or if they are not listed or
                  admitted to trading on any national securities exchange, but
                  are traded in the over-the-counter market, the closing sale
                  price of the Common Stock or, in case no sale is publicly
                  reported, the average of the representative closing bid and
                  asked quotations for the Common Stock on The Nasdaq National
                  or SmallCap Market or any comparable system, or if the Common
                  Stock is not listed on The Nasdaq Stock Market or a comparable
                  system, the closing sale price of the Common Stock or, in case
                  no sale is publicly reported, the average of the closing bid
                  and asked prices as furnished by two members of the NASD
                  selected from time to time by the Company for that purpose."

         "E.      No adjustment in the number of Warrant Shares purchasable
                  hereunder shall be required unless such adjustment would
                  require an increase or decrease of at least one percent (1%)
                  in the number of Warrant Shares purchasable upon the exercise
                  of this Warrant; provided, however, that any adjustments which
                  by reason of this paragraph (e) are not required to be made
                  shall be carried forward and taken into account in any
                  subsequent adjustment but not later than three (3) years after
                  the happening of the specified event or events. All
                  calculations shall be made to the nearest one thousandth of a
                  share."

         "F.      Whenever the number of Warrant Shares purchasable upon
                  exercise of this Warrant is adjusted, as herein provided, the
                  Per Share Warrant Price shall be adjusted by multiplying the
                  Per Share Warrant Price in effect immediately prior to such
                  adjustment by a fraction, of which the numerator shall be the
                  number of Warrant Shares purchasable upon the exercise of this
                  Warrant immediately prior to such adjustment, and of which the
                  denominator shall be the number of shares so purchasable
                  immediately thereafter."

                                       3

<PAGE>

         "G.      For the purpose of this Section III, the term "Common Stock"
                  shall mean (i) the class of stock designated as the common
                  shares of the Company at the date of this Agreement or (ii)
                  any other class of stock resulting from successive changes or
                  reclassifications of such shares consisting solely of changes
                  in par value, or from no par value to par value, or from par
                  value to no par value. If at any time, as a result of an
                  adjustment made pursuant to paragraph (a) above, the Holders
                  become entitled to purchase any shares of capital stock of the
                  Company other than Common Stock, thereafter the number of such
                  other shares so purchasable upon exercise of this Warrant and
                  the Per Share Warrant Price of such shares shall be subject to
                  adjustment from time to time in a manner and on terms as
                  nearly equivalent as practicable to the provisions with
                  respect to the Warrant Shares contained in paragraphs (a)
                  through (f), inclusive, and paragraphs (h) through (m),
                  inclusive, of this Section III, and the provisions of Sections
                  I, II, IV, and V hereof, with respect to the Warrant Shares,
                  shall apply on like terms to any such other shares."

         "H.      Upon the expiration of any rights, options, warrants or
                  conversion rights or exchange privileges that caused
                  adjustments under this Section III, such adjustments with
                  respect to any Warrants that have not been exercised shall,
                  upon such expiration, be readjusted and shall thereafter be
                  such as they would have been had such rights, options,
                  warrants or conversion rights or exchange privileges never
                  existed."

         "I.      The Company may, at its option at any time during the term of
                  the Warrants, reduce the then current Per Share Warrant Price
                  to any amount deemed appropriate by the Board of Directors of
                  the Company."

         "J.      Whenever the number of Warrant Shares issuable upon the
                  exercise of this Warrant or the Per Share Warrant Price of
                  such Warrant Shares is adjusted, as herein provided, the
                  Company shall promptly mail by first class-mail, postage
                  prepaid, to each Holder notice of such adjustment or
                  adjustments. No failure to mail such notice nor any defect
                  therein or in the mailing thereof shall affect the validity
                  thereof except as to the Holder to whom the Company failed to
                  mail such notice or whose notice was defective. A certificate
                  of an officer of the Company, on behalf of the Company, that
                  such notice has been mailed shall be prima facie evidence of
                  the facts stated therein. After any such adjustment, the

                                       4

<PAGE>

                  Company shall prepare a certificate setting forth the number
                  of Warrant Shares issuable upon the exercise of this Warrant
                  and the Per Share Warrant Price of such Warrant after such
                  adjustment, setting forth a brief statement of the facts
                  requiring such adjustment. Such certificate shall, except as
                  provided below, be conclusive as to the correctness of such
                  adjustment and each Holder shall have the right to inspect
                  such certificate during reasonable business hours. Any
                  determination as to whether an adjustment is required pursuant
                  to this Section III, or as to the amount of any such
                  adjustment, shall be initially made in good faith by the Board
                  of Directors of the Company. If the Holders of a majority of
                  the then outstanding Warrants shall, in the exercise of their
                  discretion, object to such determination, the amount of such
                  adjustment shall be made by an independent accounting or
                  investment banking firm selected by the Holders of a majority
                  of the then outstanding Warrants and reasonably acceptable to
                  the Company."

         "K.      Except as provided in this Section III, no adjustment in
                  respect of any dividends shall be made during the term of a
                  Warrant or upon the exercise of a Warrant."

         "L.      If the Company consolidates with or merges into another
                  corporation or if the Company sells or conveys all or
                  substantially all its property to another corporation, or if
                  the Company enters into a statutory share exchange with
                  another Company pursuant to which its Common Stock is
                  exchanged for, or changed into, securities or property of
                  another Company, the Company or such successor or purchasing
                  corporation (or an affiliate of such successor or purchasing
                  corporation), as the case may be, agrees that each Holder
                  shall have the right thereafter upon payment of the Aggregate
                  Warrant Price in effect immediately prior to such action to
                  purchase upon exercise of this Warrant the kind and amount of
                  shares and other securities and property (including cash)
                  which such Holder would have owned or been entitled to receive
                  after the happening of the consolidation, merger, sale,
                  conveyance or share exchange had such Warrant been exercised
                  immediately prior to such action. The provisions of this
                  paragraph (1) shall apply to successive consolidations,
                  mergers, sales, conveyances or share exchanges."

         "M.      Notwithstanding any adjustment in the Per Share Warrant Price
                  or the number or kind of shares purchasable upon the exercise
                  inches wide, 8 inches high, and 8 inches deep and weighs
                  of the

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<PAGE>

                  Warrants, certificates for Warrants issued prior or
                  subsequent to such adjustment may continue to express the same
                  price and number and kind of shares as are initially
                  issuable."

         3. AGREEMENT, AS AMENDED, CONTINUES. Except as modified by this
Amendment, the Agreement shall continue in full force according to its terms and
is hereby ratified.

         IN WITNESS WHEREOF, the Company and the Representative have executed
this Amendment as of the date set forth in the introductory paragraph of this
Amendment.

                                    SOMANETICS CORPORATION

                                    By: /s/
                                        ----------------------------------------

                                             Its:
                                                   -----------------------------

                                    BREAN MURRAY & CO., INC.

                                    By:  /s/
                                         ---------------------------------------

                                             Its:
                                                   -----------------------------

                                       6<PAGE>

                                                                    EXHIBIT 10.1

                            STOCK PURCHASE AGREEMENT

     STOCK PURCHASE AGREEMENT (this "Agreement"), dated as of October 22, 2001,
by and between Plains Resources Inc., a Delaware corporation (the "Company"),
and EnCap Investments, L.L.C., a Delaware liability company (the "EnCap").

     WHEREAS, the Company desires to repurchase 998,500 share (the "Shares") of
its common stock, par value $.10 per share (the "Common Stock") at a price of
$23.50 per share from certain entities controlled by EnCap (collectively, the
"EnCap Affiliates") under the terms and conditions set forth herein, and to
cancel and retire the Shares after such purchase.

     NOW THEREFORE, in consideration of the premises and the mutual promises
herein made, and in consideration of the representations, warranties, agreements
and covenants herein, the parties hereto agree as follows:

     1.   Sale and Purchase.

     (a)  On the Closing Date (as hereinafter defined), EnCap shall cause the
EnCap Affiliates listed on Schedule I hereto to sell, assign and transfer to the
Company the number of Shares set forth opposite such EnCap Affiliate's name on
Schedule I hereto free and clear of all security interests, pledges, mortgages,
liens, charges, encumbrances, adverse claims, restrictions, or other burdens or
encumbrances of any kind ("Encumbrances"), other than those restrictions arising
from applicable federal and state securities laws.

     (b)  At the Closing (as hereinafter defined), the Company shall pay to
EnCap, on behalf of the EnCap Affiliates, as the purchase price of the Shares,
$23.50 per share multiplied by the number of Shares sold, assigned and
transferred by the EnCap Affiliates, by wire transfer of immediately available
funds to EnCap's bank account set forth on a notice given by EnCap to the
Company not later than one (1) business day prior to the Closing Date.

          (c)  At the Closing, EnCap shall cause the EnCap Affiliates to
deliver to the Company a certificate or certificates representing such
EnCap Affiliate's Shares registered in such EnCap Affiliates' name,
together with a duly executed stock power endorsed to the Company with
signatures guaranteed by a national bank or trust company or a member
firm of the New York Stock Exchange or such other assignments or
instruments of conveyance and transfer, in form and substance
satisfactory to the Company and its counsel, as shall be effective to
vest in the Company all of such EnCap Affiliate's right, title and
interest in and to the Shares.

     2.   Representations and Warranties of EnCap.  EnCap represents
and warrants to the Company that:

     (a)  Each EnCap Affiliate is the sole record owner and is the beneficial
owner of such EnCap Affiliate's Shares; other than EnCap, no person has a right
to acquire or direct the disposition, or holds a proxy or other right to vote or
direct the vote, of the Shares; and each EnCap Affiliate has good and valid
title to the Shares, free and clear of any Encumbrances except restrictions
arising from applicable federal and state securities laws. Other than this
Agreement
<PAGE>
there is no option, warrant, right, call, proxy, agreement, commitment or
understanding of any nature whatsoever, fixed or contingent, that directly or
indirectly (i) calls for the sale, pledge or other transfer or disposition of
any of the Shares, any interest therein or any rights with respect thereto, or
relates to the voting, disposition, exercise, conversion or control of the
Shares, or (ii) obligates EnCap or any EnCap Affiliate to grant, offer or enter
into any of the foregoing.

          (b)  The sale by the EnCap Affiliates of the Shares and the delivery
of the certificates representing the Shares to the Company against receipt of
payment therefor pursuant hereto will transfer to the Company good and valid
title to the Shares, free and clear of all Encumbrances except restrictions
arising from applicable federal and state securities laws.

          (c)  EnCap has all necessary power and authority to enter into this
Agreement, to carry out its obligations hereunder, and to consummate the
transactions contemplated hereby. The execution and delivery of this Agreement
by EnCap, the performance by EnCap of its obligations hereunder, and the
consummation by EnCap of the transactions contemplated hereby have been duly
authorized by all requisite action on the part of EnCap and no other proceedings
on the part of EnCap are necessary to authorize this Agreement or the
consummation of the transactions contemplated hereby. This Agreement has been
duly executed and delivered by EnCap and constitutes a legal, valid and binding
obligation of EnCap enforceable against EnCap in accordance with its terms.

          (d)  The execution, delivery and performance of this Agreement by
EnCap does not and will not (a) violate or conflict with or result in a breach
of any provision of the organizational documents of EnCap, (b) violate or
conflict with any law or order, writ, judgment, injunction, decree, stipulation,
determination, or award (a "Governmental Order") entered into by or with any
federal, state, local, or any foreign government, governmental, regulatory, or
administrative authority, agency or commission or any court (a "Governmental
Authority") applicable to EnCap or any of its assets and properties, or (c)
conflict with, result in any violation or breach of or constitute a default (or
an event which, with the giving of notice or lapse of time, or both, would
become a default) under, require any notice or consent under, or give to others
any rights of termination, amendment, acceleration or cancellation of, or result
in any loss of any benefit, the triggering of any payment by, or the increase in
other obligation of, EnCap or the creation of any Encumbrance on any assets or
properties of EnCap pursuant to any material contract, license, permit,
franchise or other instrument or arrangement to which EnCap is a party or by
which it, or any of such assets or properties is bound or affected, except for,
in the case of clauses (b) and (c), such conflicts, violations, breaches,
defaults or other occurrences which would not (i) impair, in any material
respect, the ability of EnCap to perform its obligations under this Agreement or
(ii) prevent or materially delay the consummation of any of the transactions
contemplated hereby. The execution, delivery and performance of this Agreement
by EnCap do not and will not require any consent, waiver, approval,
authorization or other order of, action by, filing with or notification to, any
Governmental Authority, except (a) the requirements of the Securities Exchange
Act of 1934, as amended (the "Exchange Act"), and (b) any other consent,
approval, authorization, filing or notice the failure of which to make or obtain
would not (i) impair, in any material respect, the ability of EnCap to perform
its obligations under this Agreement, or (ii) prevent or materially delay the
consummation of any of the transactions contemplated hereby.

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<PAGE>
          (e)  EnCap has not entered into any agreement, arrangement or
understanding with any person which will result in the obligation of the Company
to pay any finder's fees, brokerage or agent's commissions or other like
payments in connection with the negotiations leading to this Agreement of the
consummation of the transactions contemplated hereby.

     3.   Representations and Warranties of the Company.  The Company represents
and warrants to EnCap that:

          (a)  The Company has all necessary power and authority to enter into
this Agreement, to carry out its obligations hereunder, and to consummate the
transactions contemplated hereby. The execution and delivery of this Agreement
by the Company, the performance by the Company of its obligations hereunder, and
the consummation by the Company of the transactions contemplated hereby have
been duly authorized by all requisite action on the part of the Company and no
other proceedings on the part of the Company are necessary to authorize this
Agreement or the consummation of the transactions contemplated hereby. This
Agreement has been duly executed and delivered by the Company and constitutes a
legal, valid and binding obligation of the Company enforceable against it in
accordance with its terms.

          (b)  The execution, delivery and performance of this Agreement by the
Company does not and will not (a) violate or conflict with or result in a breach
of any provision of the organizational documents of the Company, (b) violate or
conflict with any law or Governmental Order applicable to the Company or any of
its assets and properties, or (c) conflict with, result in any violation or
breach of or constitute a default (or an event which, with the giving of notice
or lapse of time, or both, would become a default) under, require any notice or
consent under, or give to others any rights of termination, amendment,
acceleration or cancellation of, or result in any loss of any benefit, the
triggering of any payment by, or the increase in other obligation of, the
Company or the creation of any Encumbrance on any assets or properties of the
Company pursuant to any material contract, license, permit, franchise or other
instrument or arrangement to which the Company is a party or by which it, or any
of its assets or properties is bound or affected, except for, in the case of
clauses (b) and (c), such conflicts, violations, breaches, defaults or other
occurrences which would not (i) impair, in any material respect, the ability of
the Company to perform its obligations under this agreement or (ii) prevent or
materially delay the consummation of any of the transactions contemplated
hereby. The execution, delivery and performance of this Agreement by the Company
do not and will not require any consent, waiver, approval, authorization or
other order of, action by, filing with or notification to, any Governmental
Authority, except (a) the requirements of the Exchange Act, and (b) any other
consent, approval, authorization, filing or notice the failure of which to make
or obtain would not (i) impair, in any material respect, the ability of the
Company to perform its obligations under this Agreement, or (ii) prevent or
materially delay the consummation of any of the transactions contemplated
hereby.

     4.   Covenants.  EnCap hereby covenants and agrees that neither it nor any
EnCap Affiliate will enter into any transaction, take any action, or by
inaction permit any event to occur, that would result in any of EnCap's
representations or warranties herein contained not being true and correct as of
(a) the time immediately after the occurrence of such transactions, action or
event and (b) the Closing Date. The Company hereby covenants and agrees that it
will not enter

<PAGE>
into any transaction, take any action, or by inaction permit any event to
occur, that would result in any of the Company's representations or warranties
herein contained not being true and correct as of (a) the time immediately
after the occurrence of such transaction, action or event and (b) the Closing
Date,

     5.   Adjustments Upon Changes in Capitalization.  In the event of any
reorganization, recapitalization, split, merger, stock split, stock dividend,
combination or exchange of shares, issuance of other securities in exchange for
Common Stock or any other change in the outstanding securities of the Company
that results in a change in the number and the kind of shares of Common Stock
or securities convertible into Common Stock, the terms "Shares" shall be deemed
to refer to and include the Shares as well as all such dividends and
distributions, and EnCap shall cause the EnCap Affiliates to deliver the Shares
and all such dividends and distributions to the Company at the Closing and the
amount to be paid per share by the Company shall be adjusted so that the total
amount to be paid by the Company hereunder remains unchanged.

     6.   Closing; Conditions to Closing.  The consummation of the transactions
contemplated by this Agreement (the "Closing") shall take place at the offices
of the Company on October 25 or if the conditions herein remain unsatisfied, on
the business day after satisfaction or waiver of the conditions set forth in
this Section 6. The date on which the Closing occurs is referred to in this
Agreement as the "Closing Date." The obligations of the Company to consummate
the transactions contemplated by this Agreement are subject to the satisfaction
of the following conditions, unless waived by the Company in writing: (a) each
of the representations and warranties made by EnCap in this Agreement being
true and correct as of the date hereof and the Closing; (b) EnCap has performed
in all respects each and every covenant and agreement contained in this
Agreement required to be performed by EnCap on or before the Closing; and (c)
the Company and EnCap shall have obtained all approvals and consents necessary
or required for the consummation of the transactions contemplated by this
Agreement.

     7.   Validity and Severability.  If any provision of this Agreement shall
be held to be illegal, invalid or unenforceable under any applicable law, then
such contravention or invalidity shall not invalidate the entire Agreement.
Such provision shall be deemed to be modified to the extent necessary to render
it legal, valid and enforceable, and if no such modification to the extent
necessary to render it legal, valid and enforceable, then this Agreement shall
be construed as if not containing the provision held to be illegal, invalid or
unenforceable and the rights and obligations of the parties hereto shall be
construed and enforced accordingly.

     8.   Governing Law.  This Agreement shall be governed by, and construed in
accordance with, the laws of the State of Texas applicable to contracts
executed in and to be performed in that state and without regard to any
applicable conflicts of law.

     9.   Expenses.  Whether or not the transactions contemplated by this
Agreement are consummated, each of the parties hereto shall pay their
respective fees and expenses incurred in connection herewith.

     10.  Entire Agreement.  This Agreement represents the entire agreement of
the parties with respect to the subject matter hereof and shall supersede any
and all previous contracts,

                                       4
<PAGE>

arrangements or understandings between the parties hereto, with respect to the
subject matter hereof.

     11.  Amendment.  This Agreement may not be amended or modified except by
any instrument in writing signed by each of, or on behalf of each of, the
parties. This Agreement may be amended or supplemented in writing by the
parties hereto with respect to any of the terms contained in this Agreement.

     12.  Assignment; Binding Effect.  Neither party shall assign any of its
respective rights, interests or obligations hereunder without the prior
written consent of the other party, which consent may be granted or
withheld in such other party's sole discretion. Subject to the preceding
sentence, this Agreement shall be binding upon and inure to the benefit of
the parties hereto and their respective successors and assigns. Nothing in
this Agreement, express or implied, is intended to confer on any person
other than the parties hereto or their respective successors and assigns any
rights, remedies, obligations or liabilities under or by reason of this
Agreement.

     13.  Notices.  All notices or communications hereunder shall be in
writing (including facsimile or similar writing) addressed as follows:

     (a)  To EnCap:

          EnCap Investments L.L.C.
          1100 Louisiana, Suite 3150
          Houston, Texas 77002
          Attention: Mr. Jason DeLorenzo

          with a copy to:

          Thompson & Knight, L.L.P.
          1200 Smith Street, Suite 3600
          Houston, TX 77002
          Telecopy: (832) 397-8049
          Attention: Michael K. Pierce

     (b)  To the Company:

          Plains Resources Inc.
          500 Dallas Street, Suite 700
          Houston, Texas 77002
          Telecopy: (713) 654-4915
          Attention: Tim Stephens
<PAGE>
Any such notice or communication shall be deemed given (i) when made, if made
by hand delivery, and upon confirmation of receipt, if made by facsimile, (ii)
one business day after being deposited with a next day courier, postage
prepaid, or (iii) three business days after being sent certified or registered
mail, return receipt requested, postage prepaid, in each case addressed as
above (or to such other address as such party may designate in writing from
time to time).

     14.  Counterparts.  This Agreement may be executed and delivered (including
by facsimile transmission) in one or more counterparts, and by the different
parties hereto in separate counterparts, each of which when executed and
delivered shall be deemed to be an original, but all of which taken together
shall constitute one and the same agreement.

     15.  Survival of Representations, Warranties, Covenants and Agreements.
The representations, warranties, covenants and agreements contained in this
Agreement shall survive the Closing Date.

     16.  Transactions.  This Agreement may be terminated and the transactions
contemplated hereby may be abandoned at any time prior to the Closing (a) by the
mutual written consent of the Company and EnCap or (b) by either party if there
has been a breach by the other party of any representation, warranty, covenant
or agreement of such other party in this Agreement which could prevent or
materially delay the consummation of the transactions contemplated hereby, or
(c) by either party (provided that such party is not in default of any material
provision of this Agreement) if the Closing has not occurred by November 2,
2001.

                            [SIGNATURE PAGE FOLLOWS]

                                       6

<PAGE>
     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first written above by their respective representatives
thereunto duly authorized.

                                 PLAINS RESOURCES INC.

                                 By           /s/ TIMOTHY T. STEPHENS
                                    -------------------------------------------
                                 Name:  Timothy T. Stephens, Esq.
                                 Title: Executive Vice President-Administration
                                        and General Counsel

                                 ENCAP INVESTMENTS L.L.C.

                                 By:         /s/ ROBERT L. ZORICH
                                    -------------------------------------------
                                 Name:  Robert L. Zorich
                                 Title: Managing Director

                                       7
<PAGE>

                                   SCHEDULE I
                                ENCAP AFFILIATES

          ENCAP AFFILIATE                          NUMBER OF SHARES
          ---------------                          ----------------

EnCap Energy Capital Fund III LP                        424,153
EnCap Energy Capital Fund III-B LP                      320,788
     BOCP Energy Partners LP                            103,784
Energy Capital Investment Co PLC                        149,775
                                                        -------
     TOTAL:                                             998,500
                                                        =======

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00032-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00032-of-00352.parquet"}]]