Document:

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                                                                    EXHIBIT 10.1

                           AMENDMENT TO LOAN AGREEMENT
                                   AND TO NOTE

         THIS AMENDMENT TO LOAN AGREEMENT AND TO NOTE (this "Amendment") dated
as of January 29, 2002, is made between VENUS EXPLORATION, a Delaware
corporation ("Borrower"), and HIBERNIA NATIONAL BANK, a national banking
association ("Lender") who agree as follows:

         A. The Borrower and the Lender entered into that certain Loan Agreement
dated as of July 6, 2001, as amended by the Waiver and Amendment dated effective
as of December 11, 2001 (as previously amended, the "Loan Agreement"). Unless
otherwise specified herein, capitalized terms used in this Amendment shall have
the meanings indicated in the Loan Agreement.

         B. The Borrower and the Lender desire to provide for the partial
release of certain Collateral in exchange for a payment on the Loan and a
reduction of the Commitment Limit, to alter the Maturity Date of the Loan, and
otherwise to provide with respect to the Loan.

         C. NOW, THEREFORE, in consideration of the terms and conditions
contained herein, and the loans and extensions of credit heretofore, now or
hereafter made to the Borrower by the Lender, the parties hereto hereby agree as
follows:

         1. The Borrower and the Lender hereby amend and restate the definition
of "Maturity Date" in Section 1.2 of the Loan Agreement to read in its entirety
as follows:

         "Maturity Date" shall mean June 30, 2002, or such earlier date on which
         the Loan is accelerated pursuant to Section 8.2 hereof.

         1. The Borrower and the Lender hereby amend the Line of Credit Note to
change the maturity date of the Line of Credit Note in the caption from July 5,
2003, to be June 30, 2002.

         2. By letter dated January 23, 2002, the Lender has approved the
release of the Lender's security interest in the Buna West Field in Hardin and
Jasper Counties, Texas, in exchange for payment to the Lender (received by
certified funds or wire transfer) received on or before February 15, 2002,
applied as permanent reductions of both the Loan and the Commitment Limit in the
amount of at least $850,000.00. The Borrower agrees to cause all of the net sale
proceeds from the sale of the Buna West Field to be paid directly to the Lender
by the buyer, to be applied to a reduction of the outstanding Loan (and causing
a permanent reduction of the Commitment Limit in a like amount, as provided
below). The Borrower and the Lender hereby amend the Loan Agreement to provide
that upon receipt by the Lender of at least $850,000.00 of net sale proceeds
from the sale of the Buna West Field, the Commitment Limit (and the Amount and
the Borrowing Base) shall be permanently reduced by a like amount as the Loan
payment. As of the date of this Amendment, the Commitment Limit is
$1,850,000.00, and shall not hereafter be increased. The Borrower and the Lender
agree that if such payment of the net sale proceeds for the Buna West Field is
received by Lender on or before January 31, 2002,

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                                      -2-

then the accompanying permanent reduction of the Commitment Limit shall be in
lieu of the automatic Monthly Borrowing Base Reduction which would otherwise
occur on the last day of January. However, if such payment is not received by
January 31, 2002, the automatic Monthly Borrowing Base Reduction shall occur on
the last day of January as provided in Loan Agreement Subsection 2.4(c) (and the
subsequent receipt of such payment shall cause an additional reduction). In
either event, the Commitment Limit and the Borrowing Base shall be subject to
the automatic Monthly Borrowing Base Reductions continuing on the last day of
February and each successive month.

         3. Except as expressly modified in Amendment, all terms and provisions
of the Loan Agreement and all terms and provisions of the Note are hereby
ratified and confirmed, and shall be and remain in full force and effect,
enforceable in accordance with their terms.

         4. The Borrower represents and warrants that there is no defense,
offset, compensation, counterclaim or reconventional demand with respect to
amounts due under, or performance of the terms of, the Note; and to the extent
any such defense, offset, compensation, counterclaim or reconventional demand or
other causes of action might exist, whether known or unknown, such items are
hereby waived by the Borrower.

         5. The Borrower agrees to pay on demand all reasonable expenses of
Lender in connection with the preparation, reproduction, execution and delivery
of this Amendment and the other instruments and documents to be delivered
hereunder (including the reasonable fees and expenses of counsel for Lender). In
addition, the Borrower shall pay any and all stamp or other taxes, recordation
fees and other fees payable in connection with the execution, delivery, filing
or recording of this Amendment and the other instruments and documents to be
delivered hereunder and agrees to hold the Lender harmless from and against any
and all liabilities with respect to or resulting from any delay or omission in
paying such taxes or fees.

         6. THIS AMENDMENT, AND THE NOTE AS AMENDED, ARE CONTRACTS MADE UNDER
AND SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE UNITED
STATES OF AMERICA AND THE STATE OF LOUISIANA.

         IN WITNESS WHEREOF, the parties hereto have caused this instrument to
be duly executed as of the date first above written.

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BORROWER:                               VENUS EXPLORATION, INC.

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

LENDER:                                 HIBERNIA NATIONAL BANK

                                        By:
                                           ------------------------------------
                                           Name:
                                           Title:<PAGE>
                                                                    EXHIBIT 10.2

                                 PROMISSORY NOTE

$1,139,215.00                   Denver, Colorado                   March 1, 2002

         FOR VALUE RECEIVED, the undersigned, VENUS EXPLORATION, INC., a
Delaware corporation ("Maker"), promises to pay to the order of ST. MARY LAND &
EXPLORATION COMPANY, a Delaware corporation ("Payee"), at its offices in Denver,
Colorado, the principal sum of ONE MILLION ONE HUNDRED THIRTY-NINE THOUSAND TWO
HUNDRED FIFTEEN AND NO/100 DOLLARS ($1,139,215.00), with interest on the unpaid
principal balance hereof prior to default or maturity at the rate of seven
percent (7%) per annum. All past due principal of and all past due interest on
this Note shall bear interest at the highest lawful rate.

         The entire principal balance of and all accrued and unpaid interest on
this Note are due and payable on May 1, 2002. This Note may be prepaid in whole
or in part without penalty. Partial prepayments shall be applied first to any
accrued and unpaid interest and the balance to principal.

         This Note is secured by, among possibly other collateral, that certain
Guaranty of even date herewith, executed by Eugene L. Ames, Jr. in favor of
Payee. Failure to describe any other collateral securing payment of the
indebtedness evidenced by this Note shall in no way impair or restrict Payee's
rights with respect to such other collateral.

         It is understood and agreed that if Maker shall default in the payment
of this Note, or if Maker shall default in the performance of any covenant in
any instrument securing payment of this Note, then the entire principal balance
of and all accrued and unpaid interest on this Note shall at once become due and
payable without notice, at the option of Payee. Failure by Payee to exercise
this option on any one or more occasions shall not constitute a waiver of the
right to exercise such option in the event of subsequent default.

         The makers, signers, sureties, and endorsers of this Note jointly and
severally waive demand, presentment, notice of dishonor, notice of intent to
demand or accelerate payment hereof, diligence in collecting, grace, notice, and
protest, and agree to one or more extensions for any period or periods of time
and partial payments, before or after maturity, without prejudice to Payee; and
if this Note shall be collected by legal proceedings or through probate or
bankruptcy court, or shall be placed in the hands of an attorney for collection
after default or maturity, Maker agrees to pay all costs of collection,
including reasonable attorney's fees.

         This Note is issued in extension and renewal of certain indebtedness
presently owing by Maker to Payee for unpaid oil and gas production revenues, as
more particularly detailed on attached Schedule I, but without prejudice to or
effect upon Payee's rights with respect to any other or additional indebtedness
owing by Maker to Payee, any collateral securing such indebtedness, and/or
Payee's rights of audit.

         All agreements between Maker and Payee, whether now existing or
hereafter arising and whether written or oral, are hereby limited so that under
no contingency, whether by reason or demand for payment or acceleration of the
maturity hereof or otherwise, shall the interest contracted for, charged, or
received by Payee exceed the Maximum Rate (as hereinafter defined). If, for any
circumstance whatsoever, interest would otherwise be payable to Payee in excess
of the Maximum Rate, the interest payable to Payee hereunder shall be reduced to
the Maximum Rate; and if for any circumstance Payee shall ever receive anything
of value deemed interest by applicable law in excess of the Maximum Rate, then
an amount equal to any such excess shall be applied to the reduction of the
principal hereof and not the payment of interest, or if such excessive interest
exceeds the unpaid balance of principal hereof, such excess shall be refunded to
Maker. All interest paid or agreed to be paid to Maker shall, to the extent
permitted by applicable law, be amortized, prorated, allocated, and spread
throughout the full period until payment in full of the principal (including the
period of any renewal or extension hereof) so that the interest hereon for such
full period shall not exceed the Maximum Rate. As used herein, "Maximum Rate"
shall mean the maximum non-usurious rate of interest that at any time, or from
time to time, may be contracted for, taken, reserved, charged, or received under
applicable law on the indebtedness evidenced by this Note, after taking into
account, to the extent required by applicable law, any and all relevant
payments, charges, or other amounts under this Note and all instruments securing
payment of this Note.

<PAGE>

         THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS OF THE STATE OF TEXAS AND THE LAWS OF THE UNITED STATES APPLICABLE TO
TRANSACTIONS IN TEXAS.

                                               VENUS EXPLORATION, INC., a
                                               Delaware corporation

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

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SECURED PROMISSORY NOTE                                                   PAGE 2

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