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EX-10.15      AGREEMENT OF SALE AND PURCHASE WITH MB EXPLORATION, LLC DATED 
              DECEMBER 15, 1998

                         AGREEMENT OF SALE AND PURCHASE


       This Agreement dated December 15, 1998, ("Agreement Date") by and between
MB Exploration, L.L.C., a Delaware Limited Liability Company (herein called
"SELLER") and Power Exploration, Inc., a Nevada corporation (herein called
"BUYER");

                              W I T N E S S E T H:

       1. PROPERTY TO BE SOLD AND PURCHASED. Seller agrees to sell and Buyer
agrees to purchase, for the consideration hereinafter set forth, and subject to
the terms and provisions herein contained, the following described properties,
rights and interests:

             (a) All right, title and interest of Seller in and to the oil, gas
       and/or mineral leases described on Exhibit A-1 hereto (and any
       ratifications and/or amendments to such leases, whether or not such
       ratifications or amendments are described on such Exhibit A-1); and

             (b) To the extent assignable, all rights, titles and interests of
       Seller in and to all presently existing and valid operating agreements,
       and other agreements and contracts which relate to any of the properties
       described in subsection (a) above, to the extent and only to the extent
       such rights, titles and interests are attributable to the properties
       described in subsection (a) above, including without limitation, those
       listed on Exhibit A-3; and

             (c) All right, title and interest of Seller in the 3D Seismic Data
       described on Exhibit A-2 hereto, and subject to the pertinent terms and
       conditions of any agreements associated therewith, as well as the
       agreements listed in (b) above.

The properties, rights and interests specified in the foregoing subsection (a)
exclusive of the properties, rights and interests excluded below, are herein
sometimes collectively called the "Oil and Gas Properties," and the properties,
rights and interests specified in the foregoing subsections (a), (b), and (c)
exclusive of the properties, rights and interests excluded below, are herein
sometimes collectively called the "Properties." The Properties do not include,
and there is hereby expressly excepted and excluded therefrom and reserved to
Seller, (a) all overriding royalty interests, net profits interests and other
non cost bearing interests described in Exhibit A-4 attached and (b) all claims
and causes of action arising, occurring or existing in favor of Seller prior to
the Agreement Date (including, but not limited to any and all contract rights,
claims receivable, revenues, recoupment rights, recovery rights, accounting
adjustments, mispayments, erroneous payments or claims of any nature in favor of
Seller and relating or accruing to any time period prior to the Agreement Date).
Buyer is aware that the interests listed on Exhibit A-1 ("Earned Interests")
include certain interests that have been earned by Seller under the Agreements
listed on Exhibit A-3, but as of the Agreement date, Seller has not received
assignment of all the Earned Interests. By this Agreement, Seller agrees to
convey at Closing any and all rights to receive any Earned Interests.

       2. PURCHASE PRICE. The purchase price for the Properties shall be Three
Hundred Fifty Thousand Dollars ($350,000.00) and shall be adjusted for any
adjustments pursuant to Section 10. The purchase price after such adjustments
shall be the Purchase Price. The Purchase Price shall be paid in cash at the
Closing as hereinafter provided.


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       3.    REPRESENTATIONS OF SELLER.

             (a)   REPRESENTATIONS.  Seller represents to Buyer that:

                   (i) ORGANIZATION AND QUALIFICATION. Seller is a limited
             liability company duly organized and legally existing and in good
             standing under the laws of the State of Delaware and is qualified
             to do business and in good standing in Texas.

                   (ii) DUE AUTHORIZATION. Seller has full power to enter into
             and perform its obligations under this Agreement and has taken all
             proper action to authorize entering into this Agreement and
             performance of its obligations hereunder.

                   (iii) APPROVALS. Other than requirements (if any) that there
             be obtained consents to assignment (or waivers of preferential
             rights to purchase) from third parties, and except for approvals
             ("Routine Governmental Approvals"), if any, required to be obtained
             from governmental entities who are lessors under leases forming a
             part of the Oil and Gas Properties (or who administer such leases
             on behalf of such lessors) which are customarily obtained
             post-closing, to Seller's knowledge (which, as used in this
             Agreement, shall mean to the actual knowledge of Seller's executive
             personnel in its office located at the address set forth in Section
             14, neither the execution and delivery of this Agreement, nor the
             consummation of the transactions contemplated hereby, nor the
             compliance with the terms hereof, will result in any default under
             any agreement or instrument to which Seller is a party or by which
             the Properties are bound, or violate any order, writ, injunction,
             decree, statute, rule or regulation applicable to Seller or to the
             Properties.

                   (iv) VALID, BINDING AND ENFORCEABLE. This Agreement
             constitutes (and the Conveyance provided for herein to be delivered
             at Closing will, when executed and delivered, constitutes) the
             legal, valid and binding obligation of Seller, enforceable in
             accordance with its terms, except as limited by bankruptcy or other
             laws applicable generally to creditor's rights and as limited by
             general equitable principles.

                   (v) LITIGATION. There are no pending suits, actions, or other
             proceedings in which Seller is a party which affect the Properties
             in any material adverse respect (including, without limitation, any
             actions challenging or pertaining to Seller's title to any of the
             Properties), or affecting the execution and delivery of this
             Agreement or the consummation of the transactions contemplated
             hereby.

             (b) DISCLAIMERS. THE EXPRESS REPRESENTATIONS AND WARRANTIES OF
       SELLER CONTAINED IN SECTION 3(A) ABOVE ARE EXCLUSIVE AND ARE IN LIEU OF
       ALL OTHER REPRESENTATIONS AND WARRANTIES, EXPRESS, IMPLIED, STATUTORY OR
       OTHERWISE, AND SELLER EXPRESSLY DISCLAIMS ANY AND ALL SUCH OTHER
       REPRESENTATIONS AND WARRANTIES. WITHOUT LIMITATION OF THE FOREGOING, THE
       PROPERTIES SHALL BE CONVEYED PURSUANT HERETO WITHOUT ANY WARRANTY OR
       REPRESENTATION WHETHER EXPRESS, IMPLIED, STATUTORY OR OTHERWISE, RELATING
       TO TITLE TO THE PROPERTIES OR RELATING TO THE CONDITION, QUANTITY,
       QUALITY, FITNESS FOR A PARTICULAR PURPOSE, CONFORMITY TO THE MODELS OR
       SAMPLES OF MATERIALS OR MERCHANTABILITY OF ANY EQUIPMENT OR ITS FITNESS
       FOR ANY PURPOSE, AND, EXCEPT AS PROVIDED OTHERWISE IN THE FIRST SENTENCE
       OF THIS PARAGRAPH, WITHOUT ANY OTHER EXPRESS, IMPLIED, STATUTORY OR OTHER
       WARRANTY OR REPRESENTATION WHATSOEVER. BUYER IS RELYING SOLELY UPON ITS
       OWN 



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       INSPECTION OF THE PROPERTIES, AND BUYER SHALL ACCEPT ALL OF THE SAME IN
       THEIR "AS IS," "WHERE IS" CONDITION. ALSO WITHOUT LIMITATION OF THE
       FOREGOING, SELLER MAKES NO WARRANTY OR REPRESENTATION, EXPRESS, IMPLIED,
       STATUTORY OR OTHERWISE, AS TO THE ACCURACY OR COMPLETENESS OF ANY DATA,
       REPORTS, RECORDS, PROJECTIONS, INFORMATION OR MATERIALS NOW, HERETOFORE
       OR HEREAFTER FURNISHED OR MADE AVAILABLE TO BUYER IN CONNECTION WITH THIS
       AGREEMENT OR MADE AVAILABLE TO BUYER BY SELLER OR BY SELLER'S AGENTS OR
       REPRESENTATIVES. ANY AND ALL SUCH DATA, RECORDS, REPORTS, PROJECTIONS,
       INFORMATION AND OTHER MATERIALS (WRITTEN OR ORAL) FURNISHED BY SELLER OR
       OTHERWISE MADE AVAILABLE OR DISCLOSED TO BUYER ARE PROVIDED BUYER AS A
       CONVENIENCE AND SHALL NOT CREATE OR GIVE RISE TO ANY LIABILITY OF OR
       AGAINST SELLER AND ANY RELIANCE ON OR USE OF THE SAME SHALL BE AT BUYER'S
       SOLE RISK TO THE MAXIMUM EXTENT PERMITTED BY LAW. PROVIDED, HOWEVER,
       SELLER WARRANTS THAT, TO ITS KNOWLEDGE, IT HAS NOT CONVEYED THE SUBJECT
       PROPERTIES TO ANY THIRD PARTY EXCEPT AS PROVIDED PURSUANT TO THE
       AGREEMENTS LISTED IN EXHIBIT A-3 OF THE AGREEMENT OF SALE AND PURCHASE
       DESCRIBED BELOW AND ANY NON-EXCLUSIVE LICENSE OF DATA DESCRIBED ON
       EXHIBIT A-2 OF THE AGREEMENT OF SALE AND PURCHASE DESCRIBED BELOW.

       4. REPRESENTATIONS OF BUYER. Buyer represents to Seller that:

             (a) ORGANIZATION AND QUALIFICATION. Buyer is a corporation duly
       organized and legally existing and in good standing under the laws of the
       State of Nevada, and is qualified to do business and in good standing in
       Texas. Buyer is also qualified to own and operate oil and gas properties
       with all applicable governmental agencies having jurisdiction over the
       Properties, to the extent such qualification is necessary or appropriate
       or will be necessary or appropriate upon consummation of the transactions
       contemplated hereby.

             (b) DUE AUTHORIZATION. Buyer has full power to enter into and
       perform its obligations under this Agreement and has taken all proper
       action to authorize entering into this Agreement and performance of its
       obligations hereunder.

             (c) APPROVALS. Other than requirements (if any) that there be
       obtained consents to assignment (or waivers of preferential rights to
       purchase) from third parties, and except for Routine Governmental
       Approvals, neither the execution and delivery of this Agreement, nor the
       consummation of the transactions contemplated hereby, nor the compliance
       with the terms hereof, will result in any default under any agreement or
       instrument to which Buyer is a party, or violate any order, writ,
       injunction, decree, statute, rule or regulation applicable to Buyer.

             (d) VALID, BINDING AND ENFORCEABLE. This Agreement constitutes (and
       the Conveyance provided for herein to be delivered at Closing will, when
       executed and delivered, constitutes) the legal, valid and binding
       obligation of Buyer, enforceable in accordance with its terms, except as
       limited by bankruptcy or other laws applicable generally to creditor's
       rights and as limited by general equitable principles.

             (e) NO LITIGATION. There are no pending suits, actions, or other
       proceedings in which Buyer is a party (or, to Buyer's knowledge, which
       have been threatened to be instituted against Buyer) which affect the
       execution and delivery of this Agreement or the consummation of the
       transactions contemplated hereby.


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             (f) KNOWLEDGEABLE BUYER, NO DISTRIBUTION. Buyer is a knowledgeable
       purchaser, owner and operator of oil and gas properties, has the ability
       to evaluate (and in fact has evaluated) the Properties for purchase, and
       is acquiring the Properties for its own account and not with the intent
       to make a distribution in violation of the Securities Act of 1933 as
       amended (and the rules and regulations pertaining thereto) or in
       violation of any other applicable securities laws, rules or regulations.

       5. CERTAIN COVENANTS OF SELLER PENDING CLOSING. Between the date of this
       Agreement and the Closing Date:

             (a)   ACCESS BY BUYER.

                   (i) RECORDS. Seller will give Buyer, or Buyer's authorized
             representatives, at Seller's office and at all reasonable times
             before the Closing Date, access to Seller's records pertaining to
             the ownership of the Properties for the purpose of conducting due
             diligence reviews contemplated by Section 6 below. Buyer may make
             copies of such records, at its expense, but shall, if Seller so
             requests, return all copies so made if the Closing does not occur.
             All costs of copying such items shall be borne by Buyer. Seller
             shall not be obligated to provide Buyer with access to any records
             or data (i) which Seller considers to be proprietary or
             confidential to it, (ii) which Seller cannot provide to Buyer
             without, in its opinion, breaching, or risking a breach of,
             agreements with other parties, or waiving, or risking waiving,
             legal privilege or (iii) any Seismic Data. BUYER RECOGNIZES AND
             AGREES THAT ALL MATERIALS MADE AVAILABLE TO IT IN CONNECTION WITH
             THE TRANSACTION CONTEMPLATED HEREBY, WHETHER MADE AVAILABLE
             PURSUANT TO THIS SECTION OR OTHERWISE, ARE MADE AVAILABLE TO IT AS
             AN ACCOMMODATION, AND WITHOUT REPRESENTATION OR WARRANTY OF ANY
             KIND AS TO THE ACCURACY AND COMPLETENESS OF SUCH MATERIALS. NO
             WARRANTY OF ANY KIND IS MADE BY SELLER AS TO THE INFORMATION
             SUPPLIED TO BUYER OR WITH RESPECT TO PROPERTIES TO WHICH THE
             INFORMATION RELATES, AND BUYER EXPRESSLY AGREES THAT ANY
             CONCLUSIONS DRAWN THEREFROM SHALL BE THE RESULT OF ITS OWN
             INDEPENDENT REVIEW AND JUDGMENT.

                   (ii) PHYSICAL INSPECTION. Seller shall make a good faith
             effort to give Buyer, or Buyer's authorized representatives, at all
             reasonable times before the Closing Date and upon adequate notice
             to Seller, physical access to the Oil and Gas Properties for the
             purpose of inspecting same. Buyer recognizes that Seller's ability
             to obtain access to such properties, and the manner and extent of
             such access, is subject to third parties. Buyer agrees to comply
             fully with the rules, regulations and instructions issued by Seller
             (and, where Properties are in the possession of other parties, such
             other parties) regarding the actions of Buyer while upon, entering
             or leaving the Properties.

                   (iii) EXCULPATION AND INDEMNIFICATION. If Buyer exercises
             rights of access under this Section or otherwise, or conducts
             examinations or inspections under this Section or otherwise, then
             (a) such access, examination and inspection shall be at Buyer's
             sole risk, cost and expense and Buyer waives and releases all
             claims against Seller (and its Members and its and their affiliates
             and the respective directors, officers, employees, attorneys,
             contractors and agents of such parties) arising in any way
             therefrom or in any way connected therewith or arising in
             connection with the conduct of its directors, officers, employees,
             attorneys, contractors and agents in connection therewith and (b)
             Buyer shall indemnify, defend and hold harmless Seller (and its
             Members and their affiliates and the respective officers,
             directors, 

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             employees, attorneys, contractors and agents of such parties) from
             any and all claims, actions, causes of action liabilities,
             damages, losses, costs or expenses (including, without limitation,
             court costs and attorneys fees), or liens or encumbrances for
             labor or materials, arising out of or in any way connected with
             such matters. THE FOREGOING RELEASE AND INDEMNIFICATION SHALL
             APPLY WHETHER OR NOT SUCH CLAIMS, ACTIONS, CAUSES OF ACTION,
             LIABILITIES, DAMAGES, LOSSES, COSTS OR EXPENSES ARISE OUT OF (i)
             NEGLIGENCE (INCLUDING SOLE NEGLIGENCE, SINGLE NEGLIGENCE,
             CONCURRENT NEGLIGENCE, ACTIVE OR PASSIVE NEGLIGENCE, BUT EXPRESSLY
             NOT INCLUDING GROSS NEGLIGENCE) OF ANY INDEMNIFIED PARTY, OR (ii)
             STRICT LIABILITY.

             (b) INTERIM OPERATION. There are no currently producing wells on
       the Properties and no drilling operations are being conducted on the
       Properties by Seller or another working interest owner which Schedule may
       be amended by Seller up to the Closing Date, except as provided in
       Schedule 5(b). Seller is not obligated to initiate or conduct or bear the
       cost, liability or expense of any operations on or proposals relating to
       the Properties on or after the Agreement Date. Seller will give Buyer
       written notice of any proposal made by a third party between the
       Agreement Date and the Closing under any of the agreements referred to in
       Section 1of this Agreement. Buyer may elect to accept said proposal, at
       Buyer's sole cost, liability, risk and expense, by notifying Seller in
       writing at least 5 days before Seller must give the third party notice of
       whether or not it accepts such proposal. If Buyer does not accept the
       proposal within the time provided above, then Seller shall have the right
       but not the obligation to accept such proposal and any and all right,
       title and interest that Seller has the right to acquire by virtue of the
       acceptance of the proposal shall be excluded from the Properties, to the
       extent of the depths drilled pursuant to the accepted proposal. Seller
       will not sell or otherwise dispose of any portion of the Oil and Gas
       Properties.

             (c) PREFERENTIAL RIGHTS AND CONSENTS. Seller will assist Buyer in
       identifying, with respect to all material, (i) all preferential rights to
       purchase ("PREFERENTIAL RIGHTS") and requirements that consents to
       assignment ("CONSENTS") be obtained which would be applicable to the
       transactions contemplated hereby and (ii) the names and addresses of
       parties holding such rights; in attempting to assist in identifying such
       Preferential Rights and Consents, and the names and addresses of such
       parties holding the same, Seller shall in no event be obligated to go
       beyond its own records. Seller is presently aware that the Oil and Gas
       Properties are subject to the Preferential Rights and Consents under the
       Agreements listed on Exhibit A-3. As identified and requested by Buyer,
       Seller will assist in preparing request, in accordance with the documents
       creating such rights, for the execution of Consents and/or waivers of
       Preferential Rights. Seller shall have no obligation other than to so
       attempt to assist in identifying such Preferential Rights or Consents and
       to assist in requesting such execution of Consents and/or waivers of
       Preferential Rights (including, without limitation, Seller shall have no
       obligation to assure that such Consents or waivers of Preferential Rights
       are obtained). Buyer shall indemnify and hold Seller (and its Members and
       its and their affiliates and the respective officers, directors,
       employees, attorneys, contractors and agents of such parties) harmless
       from and against all claims, actions, causes of action, liabilities,
       damages, losses, costs or expenses (including, without limitation, court
       costs and attorney's fees) whatsoever that arise out of the failure to
       obtain Consents or waivers of Preferential Rights with respect to any
       transfer by Seller to Buyer of any part of the Properties and with
       respect to any subsequent transfers WHETHER OR NOT SUCH CLAIMS, ACTIONS,
       CAUSES OF ACTION, LIABILITIES, DAMAGES, LOSSES, COSTS OR EXPENSES ARISE
       OUT OF NEGLIGENCE (INCLUDING SOLE NEGLIGENCE, SINGLE NEGLIGENCE,
       CONCURRENT NEGLIGENCE, ACTIVE OR PASSIVE NEGLIGENCE, BUT EXPRESSLY NOT
       INCLUDING GROSS NEGLIGENCE) OF ANY INDEMNIFIED PARTY. If a party from
       whom a waiver of a Preferential Right is requested refuses to give such
       waiver, Seller will tender to such party the required interest in the
       Property, and to the extent that such Preferential Right is exercised by
       such party, and such interest 


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       in such Property is actually sold to such party so exercising such right,
       such interest in such Property will be excluded from the transaction
       contemplated hereby.

             (d) EARNED INTEREST. For ninety days (90) after Closing, when and
       if requested by Buyer, Seller shall notify any holder of Earned Interests
       that Buyer has contracted to purchase the Earned Interests and after the
       Closing shall request that the holder of the Earned Interests assign the
       Earned Interests to Buyer as requested by Buyer. In the event any Earned
       Interests are assigned to Seller after Closing, Seller shall promptly
       assign such Earned Interest to Buyer.

       6.    DUE DILIGENCE REVIEWS.

             (a) REVIEW BY BUYER. Buyer may conduct, at its sole cost, such
       title examination or investigation, and other examinations and
       investigations, as it may in its sole discretion choose to conduct with
       respect to the Properties in order to determine whether Preferential
       Rights or Consents exist or other problems exist which would materially
       negatively impact the value of the Properties (a "Defect"). Should, as a
       result of such examinations and investigations, or otherwise, one or more
       matters come to Buyer's attention which would constitute a Defect, and
       should there be one or more of such Defects which Buyer is unwilling to
       waive and close the transaction contemplated hereby notwithstanding the
       fact that such Defects exist, Buyer shall notify Seller in writing of
       such Defects as soon as the same are identified by Buyer, but in no event
       no later than December 21, 1998 at 5:00 p.m. (such Defects of which Buyer
       so provides notice are herein called "Asserted Defects"). Such
       notification shall include, for each Asserted Defect, (i) a description
       of the Asserted Defect and the specific Property to which it relates and
       all supporting documentation reasonably necessary to fully describe the
       basis for the Defect. All Defects with respect to which Buyer fails to so
       give Seller notice will be deemed waived for all purposes. All access to
       Sellers records and the Properties in connection with such due diligence
       shall be subject and pursuant to Section 5(a) (including, without
       limitation, the exculpation and indemnification provisions contained in
       Section 5(a)(iii)).

             (b) The term Defect shall also include the following:

                   (i) PRODUCTION SALES CONTRACTS. An Oil and Gas Property is
             subject to a production sales on transport contract to which Seller
             is a signatory party (other than the Pinnacle Contract).

                   (ii) A Mortgage or other lien or encumbrances created by
             Seller and not one of the Agreements referenced in Section 1 above.

       7. CONDITIONS PRECEDENT TO THE OBLIGATIONS OF BUYER. The obligations of
       Buyer under this Agreement are subject to each of the following
       conditions being met:

             (a) REPRESENTATIONS TRUE AND CORRECT. Each and every representation
       of Seller under this Agreement shall be true and accurate in all material
       respects as of the date when made and shall be deemed to have been made
       again at and as of the time of Closing and shall at and as of such time
       of Closing be true and accurate in all material respects except as to
       changes specifically contemplated by this Agreement or consented to by
       Buyer.

             (b) COMPLIANCE WITH COVENANTS AND AGREEMENTS. Seller shall have
       performed and complied in all material respects with (or compliance
       therewith shall have been waived by Buyer) each and every covenant and
       agreement required by this Agreement to be performed or complied with by
       Seller prior to or at the Closing.


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             (c) LITIGATION. No suit, action or other proceedings shall, on the
       date of Closing, be pending or threatened before any court or
       governmental agency seeking to restrain, prohibit, or obtain material
       damages or other material relief in connection with the consummation of
       the transactions contemplated by this Agreement.

             (d) DEFECT. No Defect exists which is not waived by Buyer or cured
       as of the Closing Date.

If any such condition on the obligations of Buyer under this Agreement is not
met as of the Closing Date, or in the event the Closing does not occur on or
before the Closing Date, and (in either case) Buyer is not in material breach of
its obligations hereunder, this Agreement may, at the option of Buyer, be
terminated. In the event such a termination by Buyer occurs the parties shall
have no further obligations to one another hereunder (other than the obligations
under Sections 5(a)(iii) and 13 hereof all of which will survive such
termination).

       8. CONDITIONS PRECEDENT TO THE OBLIGATIONS OF SELLER. The obligations of
Seller under this Agreement are subject to the each of the following conditions
being met:

             (a) REPRESENTATIONS TRUE AND CORRECT. Each and every representation
       of Buyer under this Agreement shall be true and accurate in all material
       respects as of the date when made and shall be deemed to have been made
       again at and as of the time of Closing and shall at and as of such time
       of Closing be true and accurate in all material respects except as to
       changes specifically contemplated by this Agreement or consented to by
       Seller.

             (b) COMPLIANCE WITH COVENANTS AND AGREEMENTS. Buyer shall have
       performed and complied in all material respects with (or compliance
       therewith shall have been waived by Seller) each and every covenant and
       agreement required by this Agreement to be performed or complied with by
       Buyer prior to or at the Closing.

             (c) LITIGATION. No suit, action or other proceedings shall, on the
       date of Closing, be pending or threatened before any court or
       governmental agency seeking to restrain, prohibit, or obtain material
       damages or other material relief in connection with the consummation of
       the transactions contemplated by this Agreement.

             (d) DEFECT. No Defect exists which is not waived by Buyer or cured
       as of the Closing Date..

If any such condition on the obligations of Seller under this Agreement is not
met as of the Closing Date, or in the event the Closing does not occur on or
before the Closing Date, and (in either case) Seller is not in material breach
of its obligations hereunder in the absence of Buyer being in breach of its
obligations hereunder, this Agreement may, at the option of Seller, be
terminated, in which case the parties shall have no further obligations to one
another hereunder (other than the obligations under Sections 5(a)(iii) and 12
hereof, all of which will survive such termination).

       9. CLOSING.

             (a)   ACTIONS AT CLOSING. The closing (herein called the "CLOSING")
                   of the transaction contemplated hereby shall take place in
                   the offices of MB Exploration, at 12222 Merit Drive, Dallas,
                   Texas, on December 31, 1998, at 10:00 a.m. local time at the
                   location of such offices, or at such other date and time as
                   the Buyer and Seller may mutually agree upon (such date and
                   time, as changed pursuant to this section, being herein
                   called the "CLOSING DATE"). At the Closing:


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                   (i) DELIVERY OF CONVEYANCE. Seller shall execute, acknowledge
             and deliver to Buyer a conveyance of the Properties (the
             "CONVEYANCE"), in the form attached hereto as Schedule I (and with
             Exhibit A-1 and A-2 hereto, being attached thereto), effective 7
             o'clock a.m., local time at the locations of the Closing, on or
             before December 31, 1998 (herein called the "EFFECTIVE DATE").

                   (ii)  TURN OVER POSSESSION.  Seller shall, to the extent 
             Seller can do so, turn over possession of the Properties.

                   (iii) PAYMENT TO SELLER. Buyer shall deliver to the Seller,
             by wire transfer of immediately available funds to an account
             designated by Seller in a bank located in the United States, an
             amount equal to the Purchase Price.

                   (iv) Buyer and Seller shall execute and deliver to each other
             (i) the AMI and Participation Agreement with a pro forma Operating
             Agreement to be used in connection with the Participation Agreement
             all attached hereto as Exhibit 9(a)(iv)-1, (ii) the Confidentiality
             and Non-Compete Agreements attached hereto as Exhibit (a)(iv)-2.

             (b)   POST CLOSING ACTIONS.

                   (i) TRANSFER OF FILES. Seller will use reasonable efforts to
             deliver to Buyer, at Buyer's expense, and within 45 days after
             Closing, all of Seller's lease files, abstracts and title opinions
             and other similar files and records which directly relate to the
             Properties, other than those which Seller considers to be
             proprietary or confidential to it or which Seller cannot provide to
             Buyer without, in its opinion, breaching, or risking a breach of,
             agreements with other parties, or waiving, or risking waiving,
             legal privilege. Except for the 3D Seismic Data described in
             Exhibit A-2, it is expressly understood that Buyer is not
             acquiring, and Seller is not obligated to transfer to Buyer, any
             seismic data, geological or geophysical data, or other similar
             data, or any interpretations thereof or other data or records
             related thereto because of certain interests and rights retained by
             Seller by certain agreements of even date. Seller may, at its
             election, make and retain copies of any or all such files. Buyer
             shall preserve all files so delivered by Seller of a period of
             seven (7) years following Closing and will allow Seller access
             (including, without limitation, the right to make copies at
             Seller's expense) to such files at all reasonable times.

       10. CERTAIN ACCOUNTING ADJUSTMENTS.

             (a) ADJUSTMENTS FOR EXPENSES. Appropriate adjustments shall be made
       between Buyer and Seller so that on or after the Agreement Date (i) any
       delay rentals and taxes shall be paid by the party owning the Property at
       the time payment is due, (ii) except as provided in Section 5(b), all
       costs and expenses of any operation or proposals relating to the Property
       shall be borne by Buyer, (iii) all costs and expenses of any operation or
       proposal relating to the Property before the Agreement Date shall be
       borne by Seller and (iv) no consideration shall be given to the local,
       state or federal income tax liabilities of any party.

             (b) INITIAL ADJUSTMENT AT CLOSING. At least 5 days before the
       Closing Date, Seller shall provide to Buyer a statement showing its
       computations of the amount of the adjustments provided for in subsection
       (a) above based on amounts which prior to such time have actually been
       paid or received by Seller. Buyer and Seller shall attempt to agree upon
       such adjustments prior to Closing, provided that if agreement is not
       reached, Seller's computation shall be used at Closing, subject to
       further adjustment under subsection (c) below. If the amount of
       adjustments so determined which would 


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       result in a credit to Buyer exceeds the amount of adjustments so
       determined which would result in a credit to Seller, Buyer shall, as
       provided in Section 9 above, receive a credit at Closing for the amount
       of such excess, and if the converse is true, then, as provided in Section
       9 above, the amount to be paid by Buyer to Seller at Closing shall be
       increased by the amount of such excess.

             (c) ADJUSTMENT POST CLOSING. On or before 30 days after Closing,
       Buyer and Seller shall review any additional information which may then
       be available pertaining to the adjustments provided for in subsection (a)
       above, shall determine if any additional adjustments should be made
       beyond those made at Closing (whether the same be made to account for
       expenses or revenues not considered in making the adjustments made at
       Closing, or to correct errors made in the adjustments made at Closing),
       and shall make any such adjustments by appropriate payments from Seller
       to Buyer or from Buyer to Seller.

             (d) NO FURTHER ADJUSTMENTS. Following the adjustments under
       subsection(c) above, no further adjustments shall be made under this
       Section 11. Should any expenses with regard to the Properties be charged
       to Seller or Buyer after the earlier of (i) the conclusion of such
       adjustments under subsection (c) or (ii) 30 days after Closing, the same
       shall be borne by Buyer, regardless of the periods to which the same
       relate, and any bills received by Seller will be forwarded to Buyer.

       11. ASSUMPTION AND INDEMNIFICATION. Buyer shall, on the date of Closing,
agree (and, upon the delivery to Buyer of the Conveyance, shall be deemed to
have agreed), subject to the adjustments provided for in Sections 10(b) and (c),
(a) to assume, and to timely pay and perform, all duties, obligations and
liabilities relating to the ownership and/or operation of the Properties
regardless of whether the same accrued or otherwise arose before or after the
Effective Date (including, without limitation, those arising under the contracts
and agreements described in Section 1(b) above), and (b) to indemnify and hold
Seller (and its Members and its and their affiliates, and the respective
directors, officers, employees, attorneys, contractors and agents of such
parties) harmless from and against any and all claims, actions, causes of
action, liabilities, damages, losses, costs or expenses (including, without
limitation, court costs and attorneys' fees) of any kind or character arising
out of or otherwise relating to the ownership and/or operation of the Properties
regardless of whether the same accrued or otherwise arose before or after the
Effective Date. In connection with (but not in limitation of) the foregoing, it
is specifically understood and agreed that such duties, obligations and
liabilities include all matters arising out of the condition of the Properties
on the Effective Date and to comply with applicable environmental laws, rules,
regulations and orders, including conducting any remediation activities which
may be required on or otherwise in connection with activities on the
Properties), regardless of whether such condition or the events giving rise to
such condition arose or occurred before or after the Effective Date, and the
assumptions and indemnifications by Buyer provided for in the first sentence of
this section shall expressly cover and include such matters. THE FOREGOING
ASSUMPTIONS AND INDEMNIFICATIONS SHALL APPLY WHETHER OR NOT SUCH DUTIES,
OBLIGATIONS OR LIABILITIES, OR SUCH CLAIMS, ACTIONS, CAUSES OF ACTION,
LIABILITIES, DAMAGES, LOSSES, COSTS OR EXPENSES ARISE OUT OF (I) NEGLIGENCE
(INCLUDING SOLE NEGLIGENCE, SINGLE NEGLIGENCE, CONCURRENT NEGLIGENCE, ACTIVE OR
PASSIVE NEGLIGENCE, BUT EXPRESSLY NOT INCLUDING GROSS NEGLIGENCE) OF ANY
INDEMNIFIED PARTY, OR (II) STRICT LIABILITY.

       12. NO COMMISSIONS OWED. Seller agrees to indemnify and hold Buyer (and
its affiliates, and the respective officers, directors, employees, attorneys,
contractors and agents of such parties) harmless from and against any and all
claims, actions, causes of action, liabilities, damages, losses, costs or
expenses (including, without limitation, court costs and attorneys fees) of any
kind or character arising out of or resulting from any agreement, arrangement or
understanding alleged to have been made by, or on behalf of, Seller with any
broker or finder in connection with this Agreement or the transaction
contemplated hereby. Buyer agrees to indemnify and hold Seller (and its Members
and its and their affiliates and the respective officers, directors, employees,
attorneys, contractors and agents of such 



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<PAGE>   10

parties) harmless from and against any and all claims, actions, causes of
action, liabilities, damages, losses, costs or expenses (including, without
limitation, court costs and attorneys fees) of any kind or character arising out
of or resulting from any agreement, arrangement or understanding alleged to have
been made by, or on behalf of, Buyer with any broker or finder in connection
with this Agreement or the transaction contemplated hereby.

      13. NOTICES. All notices and other communications required under this
Agreement shall (unless otherwise specifically provided herein) be in writing
and be delivered personally, by recognized commercial courier or delivery
service which provides a receipt, by telecopier (with receipt acknowledged), or
by registered or certified mail (postage prepaid), at the following addresses:

      If to Buyer:     Power Exploration, Inc.
                       Attn: Mr. Guy Pyron
                       617 Chase
                       Tyler, Texas 75701
                       Fax: (903) 561-8331

      If to Seller:    MB Exploration, LLC
                       Attn: Mr. Matthew Bob
                       1222 Merit Drive, #320
                       Dallas, Texas 75251
                       (972) 726-8288

and shall be considered delivered on the date of receipt. Either Buyer or Seller
may specify as its proper address any other post office address within the
continental limits of the United States by giving notice to the other party, in
the manner provided in this Section, at least ten (10) days prior to the
effective date of such change of address.

      14. SURVIVAL OF PROVISIONS. All representations and warranties made herein
by Buyer and Seller shall be continuing and shall be true and correct on and as
of the date of Closing with the same force and effect as if made at that time
(and shall inure to the benefit of the respective successors and assigns of
Buyer and Seller, and all of such representations and warranties shall survive
the Closing and the delivery of the Conveyance. The obligations of the parties
under Section 9 (to the extent the same are, by mutual agreement, not performed
at Closing), and Sections 10, 11, 12, 13, 14 and 15 shall (subject to any
limitations set forth therein) also survive the Closing and the delivery of the
Conveyance.

      15. MISCELLANEOUS MATTERS.

            (a) FURTHER ASSURANCES. After the Closing, Seller shall execute and
      deliver, and shall otherwise cause to be executed and delivered, from time
      to time, such further instruments, notices and other documents, and do
      such other and further acts and things, as may be reasonably necessary to
      more fully and effectively grant, convey and assign the Properties to
      Buyer.

            (b) DECEPTIVE TRADE PRACTICES WAIVER. TO THE EXTENT APPLICABLE TO
      THE TRANSACTION CONTEMPLATED HEREBY OR ANY PORTION THEREOF, BUYER WAIVES
      BUYER'S RIGHTS UNDER THE PROVISIONS OF THE TEXAS DECEPTIVE TRADE PRACTICES
      - CONSUMER PROTECTION ACT, SECTIONS 17.41 ET. SEQ. OF THE TEXAS BUSINESS
      AND COMMERCE CODE, A LAW THAT GIVES CONSUMERS SPECIAL RIGHTS AND
      PROTECTIONS, AND ANY COMPARABLE ACT IN ANY OTHER STATE IN WHICH THE
      PROPERTIES ARE LOCATED; BUYER STATES THAT, AFTER CONSULTATION WITH AN
      ATTORNEY OF BUYER'S SELECTION, BUYER VOLUNTARILY CONSENTS TO THIS WAIVER.


                                       10

<PAGE>   11

            (c) PARTIES BEAR OWN EXPENSES/NO SPECIAL DAMAGES. Each party shall
      bear and pay all expenses (including, without limitation, legal fees)
      incurred by it in connection with the transaction contemplated by this
      Agreement. NOTWITHSTANDING ANYTHING HEREIN TO THE CONTRARY NEITHER PARTY
      SHALL HAVE ANY OBLIGATIONS WITH RESPECT TO THIS AGREEMENT, OR OTHERWISE IN
      CONNECTION HEREWITH, FOR ANY SPECIAL, CONSEQUENTIAL OR PUNITIVE DAMAGES.

            (d) NO SALES TAXES. No sales, transfer or similar tax will be
      collected at Closing from Buyer in connection with this transaction. If,
      however, this transaction is later deemed to be subject to sales, transfer
      or similar tax, for any reason, Buyer agrees to be solely responsible, and
      shall indemnify and hold Seller (and its affiliates, and its and their
      directors, officers, employees, attorneys, contractors and agents)
      harmless, for any and all sales, transfer or other similar taxes
      (including related penalty, interest or legal costs) due by virtue of this
      transaction on the Properties transferred pursuant hereto and the Buyer
      shall remit such taxes at that time. Seller and Buyer agree to cooperate
      with each other in demonstrating that the requirements for exemptions from
      such taxes have been met.

            (e) ENTIRE AGREEMENT. This Agreement contains the entire
      understanding of the parties hereto with respect to subject matter hereof
      and supersedes all prior agreements, understandings, negotiations, and
      discussions among the parties with respect to such subject matter
      (including, without limitation, Paragraph II, III and all other provisions
      of that certain Letter of Intent dated October 30, 1998); provided that
      any Confidentiality Agreement executed by Buyer and Seller, or any
      representative of Seller, in connection with the transaction contemplated
      hereby remains in full force and effect and is not superseded or modified
      by this Agreement.

            (f) AMENDMENTS, WAIVERS. This Agreement may be amended, modified,
      supplemented, restated or discharged (and provisions hereof may be waived)
      only by an instrument in writing signed by the party against whom
      enforcement of the amendment, modification, supplement, restatement or
      discharge (or waiver) is sought.

            (g) CHOICE OF LAW. Without regard to principles of conflicts of law,
      this Agreement shall be construed and enforced in accordance with and
      governed by the laws of the state of Texas applicable to contracts made
      and to be performed entirely within such state and the laws of the United
      States of America, except that, to the extent that the law of a state in
      which a portion of the Properties is located (or which is otherwise
      applicable to a portion of the Properties) necessary governs, the law of
      such state shall apply as to that portion of the property located in (or
      otherwise subject to the laws of) such state.

            (h) HEADINGS, TIME OF ESSENCE, ETC. The descriptive headings
      contained in this Agreement are for convenience only and shall not control
      or affect the meaning or construction of any provision of this Agreement.
      Within this Agreement words of any gender shall be held and construed to
      cover any other gender, and words in the singular shall be held and
      construed to cover the plural, unless the context otherwise requires. Time
      is of the essence in this Agreement.

            (i) NO ASSIGNMENT. Neither party shall have the right to assign its
      rights under this Agreement, without the prior written consent of the
      other party first having been obtained.

            (j) SUCCESSORS AND ASSIGNS. Subject to the limitation on assignment
      contained in subsection (j) above, the Agreement shall be binding on and
      inure to the benefit of the parties hereto and their respective successors
      and assigns.



                                       11
<PAGE>   12

            (k) NO PRESS RELEASES. Except as may be required under applicable
      law, prior to Closing neither party shall make any public announcement
      with respect to the transaction contemplated hereby without the consent of
      the other party.

            (l) COUNTERPART EXECUTION. This Agreement may be executed in
      counterparts, all of which are identical and all of which constitute one
      and the same instrument. It shall not be necessary for Buyer and Seller to
      sign the same counterpart.

      IN WITNESS WHEREOF, this Agreement is executed by the parties hereto on
the date set forth above.

                                         M B EXPLORATION, L.L.C.


                                         By:
                                            -----------------------
                                         Name:
                                              ---------------------
                                         Title:
                                               --------------------


                                         POWER EXPLORATION, INC.


                                         By:
                                            -----------------------
                                         Name:
                                              ---------------------
                                         Title:
                                               --------------------




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