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                                                                   EXHIBIT 10.13



                                 LOAN AGREEMENT

     This Loan Agreement is entered into effective the 15th day of September, 
1998, by and between Dallas Cady Family, LLP. (a Texas Limited Liability 
Corporation) ("Lender") and Power Exploration, Inc. ("Borrower").

                                   WITNESSETH

     Whereas, "BORROWER" is the owner of two truck units, serial numbers PB5142 
and PB5143 (hereinafter referred to as "Trucks"): and

     Whereas, as part of the inducement to Lender to enter into an Agreement to 
lend Fifty Thousand Dollars ($50,000), Borrower has agreed to pledge the above 
mentioned trucks. (said trucks being referred to herein as the "COLLATERAL") as 
security for its obligations;

NOW, THEREFORE, in consideration of the agreements and promises herein recited 
and contained, the sufficiency of which is hereby acknowledged, the parties 
hereto hereby agree as follows:

1.   PLEDGE OF COLLATERAL

     Borrower has agreed to and does hereby pledge for the benefit of Lender the
     COLLATERAL, said COLLATERAL being validly issued together with a duly
     executed stock transfer powers. The COLLATERAL is pledged as security for
     the payment in full of the obligations by Borrower to Lender in the amount
     of Fifty Thousand Dollars ($50,000) plus Eighty Thousand (80,000) warrants
     at an exercise price of $1.00. Lender shall have a lien upon security title
     to and a security interest in all of the COLLATERAL delivered pursuant
     hereto.

2.   WARRANTIES

     BORROWERS hereby warrants to LENDER that he is the sole and lawful owner of
     the COLLATERAL; that the COLLATERAL is free and clear of all encumbrances
     and liens and that BORROWER have full right to pledge, assign, convey and
     transfer the COLLATERAL as provided herein.

3.   TERMS AND CONDITIONS

     LENDER by their execution of the loan Agreement, accept the pledge of the
     COLLATERAL hereunder and agree to hold the COLLATERAL in accordance with
     the provisions hereof and applicable law.
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4.   REMEDIES FOR DEFAULT

     A.   The following constitutes a default hereunder:

          (i)   Failure by BORROWER to pay LENDER, on or before January 15, 1999
                the sum of Fifty Thousand Dollars ($50,000) plus Eighty Thousand
                (80,000) warrants at an exercise price of $1.00.; or

          (ii)  The breach of any of the warranties, representations, covenants,
                or agreements applicable to the acquisition of the securities,
                the subject matter of this Loan Agreement, and the failure to
                cure the same after receipt of written notice as is set forth
                therein.

     B.   Upon the occurrence of a default, LENDER;

          (i)   At any time thereafter, so long as such default is continuing 
                and, at its option, exercise its rights under this Loan 
                Agreement;

          (ii)  Vote all or any part of the COLLATERAL (whether or not 
                transferred into its name or the name of the nominee or nominees
                as provided below) and give all consents, waivers and
                ratifications in respect thereof and otherwise act with respect
                thereto as though it were the outright owner thereof;

          (iii) Exercise from time to time any right and remedies available 
                under the Uniform Commercial Code as in effect at that time; and

          (iv)  Subject to any requirements of applicable law, and without 
                limiting any rights otherwise available hereunder or under law,
                transfer into its name, or into the name of any nominee or
                nominees LENDER may appoint, all or part of the COLLATERAL and
                retain the same in full satisfaction from any further; or sell,
                assign and deliver the COLLATERAL at public or private sale for
                cash, on credit or for other property, of immediate or future
                delivery, without any assumption of credit risk, and for such
                price or prices and on such terms as in LENDER'S uncontrolled
                discretion may determine.

                If any notification of intended disposition of any of the
                COLLATERAL is required by law, such notification shall be deemed
                reasonable and properly given if in writing and mailed at least
                thirty (30) days before such disposition by prepaid registered
                or certified mail, addressed to the address specified below.

     C.   If sold at public sale, any proceeds of any disposition of the 
          COLLATERAL may by applied to the payment of expenses in connection
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         with the COLLATERAL, including reasonable attorney's fees and legal
         expenses, and any balance of such proceeds after Fifty Thousand Dollars
         ($50,000) and expenses shall be returned. No delay or failure on the
         part of LENDER the exercise of any right or remedy hereunder shall
         operate as a waiver thereof, and no remedy hereunder shall preclude any
         further exercise thereof or the exercise of any other right or remedy
         hereunder.

6.  TERMINATION

    Upon the payment to LENDER from any source the sum of Fifty Thousand Dollars
    ($50,000) plus Eighty Thousand (80,000) warrants at an exercise price of
    $1.00., this Loan Agreement shall terminate and LENDER shall cancel all
    related agreements and/or deliver the COLLATERAL to BORROWER or the
    designees of BORROWER.
        

7.  SUCCESSORS AND ASSIGNS

    LENDER and BORROWER agree that this Loan Agreement shall be binding upon,
    inure to benefit of and be enforceable by the parties hereto and their
    respective heirs, personal representatives, successors and assigns.


8.  ATTORNEYS FEES

    If action be instituted regarding this Pledge Agreement the prevailing party
    shall be entitled to reasonable attorney's fees and costs.

9.  PRIOR AGREEMENTS

    This Pledge Agreement constitutes the entire agreement between the parties
    with respect to the subject matter hereof.

10. NOTICES

    All notices, offers, acceptances and other communications hereunder shall be
    made in writing signed by the party making the same, and shall be deemed
    delivered on the date mailed if sent by certified or registered United
    States mail, postage prepaid, to the addresses set forth below:

    Dallas Cady Family, LLP 
    C/O Robert Cady 
    1700 Commerce St., Ste. 700 
    Dallas, Texas 75201
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    Mark Zouvas
    C/O Power Exploration, Inc.
    5020 Collinwood Avenue, Suite 201
    Fort Worth, Texas 76107

    Or such other address as either party may specify by written notice to the
    other party

11. APPLICABLE LAW

    This Pledge Agreement shall be construed in accordance with and governed by
    the laws of the State of Nevada.

12. COUNTERPART

    This Pledge Agreement may be executed in counterpart and each copy so
    executed shall be considered an original.

    IN WITNESS WHEREOF, the following have executed and delivered and have
    accepted this Pledge Agreement on the date given above.



    LENDER:                                  BORROWER:

    DALLAS-CADY                              POWER EXPLORATION, INC
    FAMILY, L.L.P.                           


    By: /s/ ROBERT CADY                      By: /s/ MARK ZOUVAS
       -----------------------                  -----------------------
       Robert Cady                              Mark Zouvas, CFO