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                                                                  EXHIBIT 10.25


                                     MASTER
                                PROMISSORY NOTE
$5,000,000.00                     (this "Note")                   MARCH 6, 1997

     FOR VALUE RECEIVED, the undersigned, TITAN RESOURCES, L.P., a Texas
limited partnership ("Company") promises to pay to the order of TEXAS COMMERCE
BANK NATIONAL ASSOCIATION ("BANK"), on or before March 6, 1998 ("Final Maturity
Date") at its offices located at 712 Main Street, Houston, Texas 77002 in
lawful money of the United States of America and in immediately available
funds, the principal amount of each loan (a "Loan") shown in Bank's records to
have been made by Bank and on the relevant maturity date as set forth in Bank's
records. Each Loan shall also have its own date of maturity agreed by Company
and Bank which will occur prior to the Final Maturity Date. The rate of
interest on each Loan evidenced hereby from time to time shall be the interest
rate which shall be determined for each Loan by agreement between Company and
Bank but, in no event, shall exceed the maximum interest rate permitted under
applicable law ("Highest Lawful Rate"). If Texas law determines the Highest
Lawful Rate, Bank has elected the "indicated" (weekly) ceiling as defined in
the Texas Credit Code or any successor statue. All past due amounts shall bear
interest at a per annum interest rate equal to the Prime Rate plus one percent
(1%) "Prime Rate" means the rate determined from time to time by Bank as its
prime rate. The Prime Rate shall change automatically from time to time without
notice to Borrower or any other person. THE PRIME RATE IS A REFERENCE RATE AND
MAY NOT BE BANK'S LOWEST RATE.

     Interest on each Loan shall be: (i) computed on the unpaid principal
amount of the Loan outstanding from the date of advance until paid; (ii)
payable at maturity and thereafter on demand; and (iii) shall be calculated on
the basis of a year of 360 days for the actual days elapsed.

     The total amount of interest (as defined under applicable law) contracted
for, charged or collected under this Note will never exceed the Highest Lawful
Rate. If Bank contracts for, charges or receives any excess interest, it will
be deemed a mistake. Bank will automatically reform the contract or charge to
conform to applicable law, and if excess interest has been received, Bank will
either refund the excess or credit the excess on the unpaid principal amount of
this Note. All amounts constituting interest will be spread throughout the full
term of this Note in determining whether interest exceeds lawful amounts.

     Each of the following is an event of default ("Events of Default"):

     (a)  Company shall fail to pay any amount of principal of or interest on
          this Note when due;

     (b)  Company shall fail to pay when due any amount of principal or
          interest with respect to any obligation to Bank (other than this
          Note); or

     (c)  Company shall fail to pay any amount relating to any other
          indebtedness for borrowed money or other pecuniary obligation
          (including any contingent such obligation) or an event or condition
          shall occur or exist which gives the holder of any such indebtedness
          or obligation the right or option to accelerate the maturity thereof.

     (d)  Company shall commence any bankruptcy, reorganization or similar case
          or proceeding relating to it or its property under the law of any
          jurisdiction, or a trustee or receiver shall be appointed for itself
          or any substantial part of its property;

     (e)  any involuntary bankruptcy, reorganization or similar case or
          proceeding under the law of any jurisdiction shall have been
          commenced against Company or any substantial part of its property and
          such case or proceeding shall not have been dismissed within 60 days,
          or Company shall have consented to such case or proceeding; or

     (f)  Company shall admit in writing its inability to pay its debts as they
          become due.

     Upon the happening of any Event of Default specified in paragraphs (d),
(e) or (f) above, automatically the Loans evidenced by this Note (with accrued
interest thereon) shall immediately become due and payable, and upon the
happening of an Event of Default specified in paragraphs (a), (b) or ( c )
above, Bank may, by notice to Company, Declare the Loans evidenced by this Note
(with accrued interest thereon) to be due and payable, whereupon the same shall
immediately become due and payable. Except as expressly provided above,
presentment, demand, protest, notice of intent to accelerate, acceleration and
all other notices of any kind are hereby expressly waived.

     The Company hereby agrees to pay on demand, in addition to unpaid
principal and interest, all Bank's costs and expenses incurred in attempting or
effecting collection hereunder, including the reasonable fees and expenses of
counsel (which may include, to the extent permitted by applicable law,
allocated costs of in-house counsel), whether or not suit is instituted.

     This Note is executed and delivered by Company to evidence Loans which may
be made by Bank to Company not to exceed $5,000,000.00. COMPANY UNDERSTANDS
THAT BANK HAS NO OBLIGATION TO MAKE ANY LOAN TO COMPANY UNDER THIS NOTE.

     All Loans evidenced by this Note are and will be for business and
commercial purposes and no Loan will be used for the purpose of purchasing or
carrying any margin stock as that term is defined in Regulation U of the Board
of Governors of the Federal Reserve System (the "Board").

     Chapter 15 of the Texas Credit Code does not apply to this Note or to any
Loan evidenced by this Note. This Note shall be governed by the laws of the
State of Texas and the laws of the United States as applicable.

     Bank shall, and is hereby authorized by Company, to record in its records
the date, amount, interest rate and due date of each Loan as well as the date
and amount of each payment by the undersigned in respect thereof. Payments may
be applied to accrued interest or principal in whatever order Bank chooses.

     Loans evidenced by this Note may not be prepaid. In the event any such
prepayment occurs, Company shall indemnify Bank against any loss, liability,
damage, cost or expense which Bank may sustain or incur as a consequence
thereof, including without limitation any loss, liability, damage, cost or
expense sustained or incurred in liquidating or employing deposits from third
parties acquired to effect or maintain such Loan or any part thereof. Bank
shall provide to Company a written statement explaining the amount of any such
loss or expense, which statement shall be conclusive absent manifest error.

     No waiver of any default shall be deemed to be a waiver of any other
default. No failure to exercise or delay in exercising any right or power under
this Note shall operate as a waiver thereof, nor shall any single or partial
exercise of any such right or power preclude any further or other exercise
thereof or the exercise of any other right or power. No amendment, modification
or waiver of this Note shall be effective unless the same is in writing and
signed by the person against whom such amendment, modification or waiver is
sought to be enforced. No notice to or demand on any person shall entitle any
person to any other or further notice or demand in similar or other
circumstances.

     This Note shall be binding upon the successors and assigns of Company and
inure to the benefit of Bank, its successors, endorsees and assigns
(furthermore, Bank may assign or pledge this Note or any interest therein to
any Federal Reserve Bank). If any term or provision of this Note shall be held
invalid, illegal or unenforceable the validity of all other terms and
provisions will not be affected.

     THIS NOTE REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT
BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES.

          THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

                                    TITAN RESOURCES, L.P., a Texas limited
                                    partnership

                                    By:  TITAN RESOURCES I INC., its General
                                         Partner

                                    By:  /s/  Jack Hightower
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                                    Name:  Jack Hightower
                                    Title:  President

(The Bank's signature is provided as
its acknowledgment of the above as
the final written agreement between the parties.)

TEXAS COMMERCE BANK NATIONAL ASSOCIATION

By: /s/ Sandra Aultman
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Name:  Sandra Aultman
Title:  Vice President




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