FIRST AMENDMENT AND SUPPLEMENT TO
                           PURCHASE AND SALE AGREEMENT


         This FIRST AMENDMENT AND SUPPLEMENT TO PURCHASE AND SALE AGREEMENT (the
"Amendment") is made and entered into as of the 26th day of September,  1996, by
and  between  MOBIL OIL  EXPLORATION  &  PRODUCING  SOUTHEAST  INC.,  a Delaware
corporation  ("Seller"),  with a place of business at 12450  Greenspoint  Drive,
Houston,  Texas 77060-1991,  and FLORES & RUCKS,  INC., a Louisiana  corporation
("Purchaser"),  with a place of  business  at 500 Dover  Boulevard,  Suite  300,
Lafayette, Louisiana 70503.

         WHEREAS,  Seller and Purchaser have entered into that certain  Purchase
and Sale Agreement dated July 10, 1996 (the "Purchase and Sale Agreement "); and

         WHEREAS,  pursuant  to  the  Purchase  and  Sale  Agreement,  Purchaser
delivered to Seller a Notice of Title  Defects,  by letter dated  September  13,
1996 (the "Notice of Title Defects"); and

         WHEREAS,  Seller  and  Purchaser  desire  to amend and  supplement  the
Purchase and Sale  Agreement  to advance the Closing  Date,  substitute  certain
Exhibits and to agree with respect to certain closing and post closing matters.

         NOW, THEREFORE, in consideration of the mutual benefits and obligations
of Seller and Purchaser  included herein and in the Purchase and Sale Agreement,
Seller and Purchaser do hereby agree as follows:

1.   Closing  Date:  Article  4 of the  Purchase  and Sale  Agreement  is hereby
     amended  to  delete  "September  30,  1996,"  and  to  substitute  therefor
     "September 26, 1996."

2.   Operations: Article 17 of the Purchase and Sale Agreement is hereby amended
     to delete the first two sentences and to substitute therefor the following:

                  Seller,  as to the  portion of the  Interests  to be  conveyed
                  which it now  operates,  shall,  from the date of execution of
                  this  Agreement,  continue  to operate  the same in a good and
                  workmanlike  manner until October 1, 1996, at 7:00 a.m.,  when
                  such  operations  shall  be  turned  over  to and  become  the
                  responsibility  of  Purchaser,   unless  an  applicable  unit,
                  pooling,   communitization  or  operating  agreement  requires
                  otherwise or any necessary  Designation of Operator forms have
                  not been  executed  and  filed  with the  Minerals  Management
                  Service  ("MMS"),  in which case (unless  Purchaser and Seller
                  otherwise agree) Seller shall continue the physical  operation
                  of such  portion of the  Interests  pursuant  to and under the
                  terms of such  applicable  agreement or as required by the MMS
                  until such time as such  applicable  agreement  may require or
                  until any necessary


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                  Designation  of Operator  forms have been  executed  and filed
                  with the MMS;  provided,  however,  that Seller  shall have no
                  liability  as  operator  to  Purchaser  for  losses or damages
                  sustained, or liabilities incurred, WHETHER OR NOT THE LOSSES,
                  COSTS, EXPENSES AND DAMAGE IN QUESTION AROSE SOLELY OR IN PART
                  FROM  THE  ACTIVE,   PASSIVE,   CONCURRENT,   SIMPLE  OR  SOLE
                  NEGLIGENCE,  OR STRICT  LIABILITY  OR OTHER FAULT OF SELLER OR
                  ANY  OTHER  THEORY  OF  LIABILITY  OR  FAULT,  WHETHER  IN LAW
                  (WHETHER COMMON OR STATUTORY) OR EQUITY,  except as may result
                  directly from Seller's gross negligence or willful misconduct.
                  Any  operations  from and after the  Effective  Time  shall be
                  conducted by Seller for and on behalf of Purchaser  and, after
                  the Closing Date,  subject to  Purchaser's  sole direction and
                  right of control. Seller shall make appropriate charges to the
                  Purchaser  for such  services as operator of the Interests (or
                  any portion  thereof)  performed  by Seller from and after the
                  Effective Time.

3.   Exhibits:  Exhibits  "A-1"  though  "A-13" and "B" to the Purchase and Sale
     Agreement  are  hereby  amended  by  deleting  same in their  entirety  and
     substituting  therefor Exhibits "A-1" though "A-13" and "B" attached hereto
     as Attachment No. 1.

4.   Indemnification  for Liens and Judgments:  Seller shall defend,  indemnify,
     save,  discharge,  release  and hold  Purchaser  harmless  from any and all
     Claims  arising  out of or  related  to the liens and  judgments  listed in
     Sub-Paragraphs  "1.a"  through  "v" and in  Paragraph  "3" of the Notice of
     Title Defects.  The provisions of Subsection  21.01(f) and Section 21.02 of
     the Purchase and Sale Agreement shall be applicable to claims for indemnity
     under this paragraph.

5.   Indemnification for Gas Purchase Contracts and Production Payments:  Seller
     shall  defend,  indemnify,  save,  discharge,  release  and hold  Purchaser
     harmless  from any and all  Claims  arising  out of or  related  to the Gas
     Purchase  Contracts,  Production Payments and Mortgage listed in Paragraphs
     "2," "7," "11.a" through "c", and "12" of the Notice of Title Defects.  The
     provisions  of  Subsection  21.01(f) and Section  21.02 of the Purchase and
     Sale  Agreement  shall be  applicable  to claims for  indemnity  under this
     paragraph.

6.   Outstanding Preferential Rights to Purchase:  Article 7 of the Purchase and
     Sale Agreement  provides that Seller and Purchaser may agree on a procedure
     to accommodate outstanding  Preferential Rights. Seller and Purchaser agree
     to the following  procedure with regard to any  Properties  where there are
     outstanding  Preferential  Rights  which have not expired or been  properly
     waived by the Closing Date.  Seller shall execute and deliver an assignment
     as to any such Property and Purchaser  shall pay the allocated  Sales Price
     for such Property at Closing.  Purchaser will hold said assignment and will
     not submit same for  recordation  in any parish or for  approval by the MMS
     until the Preferential  Rights covering such Property expire or are waived.
     In the event the Preferential Rights are exercised, within five (5) days of
     notification  of exercise,  Purchaser shall return to Seller the assignment
     for such Property as to which the  Preferential  Rights were  exercised and
     Seller shall  simultaneously  return to Purchaser the allocated Sales Price
     for such Property. In the event the Preferential Rights are exercised, the


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     assignment for such Property shall be null and void and Purchaser  shall be
     deemed to have not assumed any  obligations or liabilities  with respect to
     such Property.

7.   Post Closing  Curative:  Subsections  6.03 through 6.05 of the Purchase and
     Sale  Agreement  address the  notification  and handling of Title  Defects.
     These provisions do not specifically address post closing curative matters.
     Article  24 of  the  Purchase  and  Sale  Agreement  provides  the  further
     assurance obligations of Seller and Purchaser. Without limiting the further
     assurance obligations of Purchaser or Seller, Purchaser and Seller agree to
     the following.

         a.       Vermilion 215 Field:

                    i.   Vermilion  215  Field  Curative:  Reference  is made to
                         Paragraphs "5" (including  Requirements Nos. "5.a", "b"
                         and "c" thereunder) and "6" (including  Requirement No.
                         "6"  thereunder)  of the Notice of Title  Defects.  The
                         assignments and other curative required ("Vermilion 215
                         Field  Curative")  have  not  been  obtained  as of the
                         Closing Date.

                    ii.  Closing: Seller shall execute and deliver at Closing to
                         Purchaser:  (1) an Assignment of Record Title  Interest
                         and  Bill of  Sale  for  Vermilion  215  Field;  (2) an
                         Assignment  of  Overriding  Royalty  Interests;  (3) an
                         Assignment of Operating  Rights;  and (4) an Assignment
                         of Interests in Wells.  Purchaser  shall pay at Closing
                         the  allocated  Sales Price for the Vermilion 215 Field
                         Property.  Purchaser  shall  not  file  in  the  Parish
                         Records  or  with  the MMS  "(3)"  and  "(4),"  pending
                         receipt from Seller of the Vermilion 215 Field Curative
                         or the expiration of the time period under iii below.

                  iii.     Post Closing Curative

                    (1)  Seller  shall  attempt,  for a period  of up to six (6)
                         months after the Closing  Date, to obtain the execution
                         of and deliver to  Purchaser  the  Vermilion  215 Field
                         Curative.

                    (2)  If said  curative  is not  executed  and  delivered  to
                         Purchaser  within thirty (30) days of the Closing Date,
                         Purchaser  shall have right to demand the return of the
                         allocated  Sales Price for the affected  portion of the
                         Interests(being $9,000,000.00). If Purchaser makes said
                         demand, Seller shall pay the return payment within five
                         (5) days after the  expiration  of the thirty  (30) day
                         period and  Purchaser  shall  simultaneously  return to
                         Seller  assignments  "(3)" and "(4)"  referenced  above
                         under "ii".
                    
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                    (3)  If the return  payment has been made and the  Vermilion
                         215  Field   Curative  is  executed  and  delivered  to
                         Purchaser  within the  aforesaid  six (6) month period,
                         Purchaser  shall  repay the  allocated  Sales  Price to
                         Seller.  Said  repayment  shall be made within five (5)
                         days of the delivery to Purchaser of said  curative and
                         Seller  shall  simultaneously  redeliver  to  Purchaser
                         assignments  "(3)" and  "(4)"  referenced  above  under
                         "ii".

                    (4)  If the  Vermilion  215 Field  Curative is not  obtained
                         within  six  (6)  months  of  the  Closing  Date,  then
                         Purchaser  shall have the option to elect between:  (a)
                         the  return  of  the  allocated  Sales  Price,  or  (b)
                         receiving  an  assignment  of  any  contractual  rights
                         Seller may have to demand said  curative.  If there has
                         been a prior return  payment,  then upon electing "(a)"
                         Purchaser  will  retain  the  return  payment,  or upon
                         electing  "(b)"  Purchaser  shall  repay the  allocated
                         Sales Price  within five (5) days of such  election and
                         Seller  shall  simultaneously  redeliver  to  Purchaser
                         assignments  "(3)" and  "(4)"  referenced  above  under
                         "ii".  If there has been no prior  return  payment  and
                         Purchaser elects "(a)", then within five (5) days after
                         the  expiration  of the  aforesaid six (6) month period
                         Seller shall return the  allocated  Sales Price for the
                         affected  portion of the Interests and Purchaser  shall
                         simultaneously  return to Seller  assignments "(3)" and
                         "(4)" referenced above under "ii".

                    (5)  An accounting will be made between the Seller and Buyer
                         for revenue and expenses for the applicable  periods in
                         the event of any return payment or repayment. By way of
                         illustration:  (a) if there is a return  payment  after
                         the end of thirty  (30) days,  then the return  payment
                         shall be adjusted according to the revenue and expenses
                         between  the  Effective  Date and the end of the thirty
                         (30) day period;  and (b) if there is a repayment  then
                         the  repayment  shall  be  adjusted  according  to  the
                         revenue and expenses between the end of the thirty (30)
                         day period and the date of the repayment.

         b.       Eugene Island 45 Field Curative:

                    i.   Walter,  et  al  Reassignment:  Reference  is  made  to
                         Paragraph   "9"   (including    Requirement   No.   "9"
                         thereunder)  of  the  Notice  of  Title  Defects.   The
                         reassignment of operating  rights from Walter Oil & Gas
                         Corporation  and/or its  successors  and  assigns  (the
                         "Walter,  et al Reassignment") has not been obtained as
                         of the Closing  Date.  Seller shall execute and deliver
                         at Closing to  Purchaser:  (1) an  Assignment of Record
                         Title  Interest and Bill of Sale for the Eugene  Island
                         45 Field  Property;  (2) an  Assignment  of  Overriding
                         Royalty

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                         Interest; and (3 )an  Assignment of  Operating  Rights.
                         Purchaser  shall pay at  Closing  the  allocated  Sales
                         Price for the Eugene Island 45 Field  Property.  Seller
                         shall use its best  efforts to obtain the  execution of
                         the Walter,  et al  Reassignment  and  deliver  same to
                         Purchaser  within thirty (30) days of the Closing Date.
                         If the Walter,  et al.,  Reassignment  is not  obtained
                         within said  thirty (30) day period,  there shall be no
                         return of the allocated  Sales Price for such Property,
                         but Seller  shall  continue to use its best  efforts to
                         obtain said reassignment.

                    ii.  Newfield  Abandonment:  Pursuant to a Farmout Agreement
                         dated April 1, 1993,  between  Seller,  as Farmor,  and
                         Newfield Exploration Company  ("Newfield"),  as Farmee,
                         as amended by Letter  Agreement  dated August 10, 1994,
                         Mobil  became  obligated,  upon  the  drilling  of  the
                         contract  well in  compliance  with  the  terms  of the
                         Farmout,  to assign Newfield certain  operating rights.
                         The contract  well, the Eugene Island Block 51 #8 Well,
                         was drilled and Seller  elected to retain an overriding
                         royalty  interest.  No  assignment  has been  made from
                         Seller to Newfield,  subject to the retained overriding
                         royalty  interest.  Newfield has notified Seller of its
                         intention to plug and abandon or to turn over said well
                         to Seller,  and to return any interest  that would have
                         been  assigned.  Seller  shall use its best  efforts to
                         obtain a  reassignment  from  Newfield of the operating
                         rights  and/or  obtain an  agreement,  satisfactory  to
                         Purchaser,  turning over said well and recognizing that
                         the assignment and reassignment are no longer necessary
                         and that  Newfield  relinquishes  its  interest  in any
                         operating  rights,  within  thirty  (30)  days  of  the
                         Closing Date. If the  reassignment  or agreement is not
                         obtained  within said  thirty  (30) day  period,  there
                         shall be no return  of the  allocated  Sales  Price for
                         such  Property,  but Seller  shall  continue to use its
                         best efforts to obtain said reassignment or agreement.

8.       Estimated Revenue and Expenses: Seller and Purchaser hereby agree to an
         adjustment  to the Sales  Price to be paid at closing to deduct the sum
         of $4,500,000.00,  being the estimated revenues net of expenses for the
         months of August and September,  1996.  Seller and Purchaser  recognize
         that  this  is an  estimate  and is  subject  to  adjustment  at  Final
         Accounting.

9.       Ratification of Purchase and Sale Agreement:  Except as amended hereby,
         the Purchase and Sale  Agreement is ratified and  confirmed in all res-
         pects and shall continuein full force and effect as originally written.

10.      Successors and Assigns:  The provisions of this Amendment shall be
         binding upon and inure to the benefit of the parties  hereto and their
         respective permitted successors and assigns.



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11.      Defined Terms:  Capitalized terms used but not defined herein shall
         have the meanings ascribed to them in the Purchase and Sale Agreement.

         IN WITNESS  WHEREOF,  the  Purchaser  and  Seller  have  executed  this
Amendment as of the date first written above.

                                              SELLER:

ATTEST:                                       MOBIL OIL EXPLORATION &
                                              PRODUCING SOUTHEAST INC.

By: /s/ B.D. Martiny                          BY:   /s/ H. L. Hickey
    --------------------------                      ----------------------
Name: B. D. Martiny                           Name: H. L. Hickey
Title: Assistant Secretary                    Title: Attorney-in-fact


                                              BY:   /s/ D. B. Litchfield
                                                    ----------------------
                                              Name: D. B. Litchfield
                                              Title: Attorney-in-fact

                                              PURCHASER:

                                              FLORES & RUCKS, INC.

                                              BY:   /s/Richard G. Zepernick, Jr.
                                                    ----------------------------
                                              Name:  Richard G. Zepernick, Jr.,
                                              Title: Executive Vice President &
                                                       Chief Operating Officer


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