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                                                                    EXHIBIT 10.2

            SECOND AMENDMENT AND SUPPLEMENT TO MORTGAGE, ASSIGNMENT
           OF PRODUCTION, SECURITY AGREEMENT AND FINANCING STATEMENT


       THIS SECOND AMENDMENT AND SUPPLEMENT TO MORTGAGE, ASSIGNMENT OF
PRODUCTION, SECURITY AGREEMENT AND FINANCING STATEMENT (this "AMENDMENT") is
entered into as of the effective time and date hereinafter stated (the
"EFFECTIVE DATE") by and between OCEAN ENERGY, INC. (formerly known as Flores &
Rucks, Inc.), a Louisiana corporation whose address for notice hereunder is
8440 Jefferson Highway, Suite 420, Baton Rouge, Louisiana  70809 (the
"MORTGAGOR"), and THE CHASE MANHATTAN BANK, a New York banking corporation with
offices and banking quarters 270 Park Avenue, New York, New York  10017, as
agent (in such capacity, "AGENT"), for the banks which are or become parties to
the Credit Agreement (hereinafter defined) and their successors and assigns
(each bank individually called "LENDER" and collectively called the "LENDERS",
with the Agent acting on behalf of the Lenders hereunder referred to as
"MORTGAGEE").

                                R E C I T A L S

       A.     Mortgagor, Mortgagee (formerly known as The Chase Manhattan Bank,
N.A.), and certain of the Lenders previously entered into a Credit Agreement
dated as of December 7, 1994, as amended by First Amendment to Credit Agreement
dated as of December 31, 1994, by Second Amendment to Credit Agreement dated as
of August 14, 1996; and as amended by that certain Amended and Restated Credit
Agreement dated March 27, 1997 (collectively, the "PRIOR CREDIT AGREEMENT").

       B.     The Prior Credit Agreement is secured by, among other things,
that certain Mortgage, Assignment of Production, Security Agreement and
Financing Statement dated as of December 7, 1994 from Mortgagor to Mortgagee
for the benefit of itself and the lenders signatory to the Prior Credit
Agreement as amended and supplemented by that certain First Amendment and
Supplement to Mortgage, Assignment of Production, Security Agreement and
Financing Statement dated as of March 27, 1997 (collectively, the "MORTGAGE").

       C.     The Mortgage was duly recorded as set forth in Schedule 1
attached hereto.

       D.     Of even date herewith, Mortgagor, Mortgagee and the Lenders are
entering into that certain Second Amended and Restated Credit Agreement (the
"CREDIT AGREEMENT") which amends and restates the Prior Credit Agreement and
the loans and indebtedness evidenced thereby in their entirety.

       E.     Mortgagor and Mortgagee now desire to amend certain terms and
provisions of the Mortgage and to supplement the Mortgage and Exhibit A thereto
to subject to the lien and security interest of the Mortgage the additional
properties described on Exhibit A-1 attached hereto.

       NOW, THEREFORE, in view of the foregoing, Mortgagor and Mortgagee do
hereby agree as follows:

       1.     All capitalized terms used but not defined herein shall have the
meanings assigned to such terms in the Mortgage.

       2.     All references in the Mortgage to "this Mortgage", as defined in
the opening paragraph of the Mortgage shall mean the Mortgage as amended and
supplemented hereby and as the same may from time to time be further amended or
supplemented.
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       3.     All references in the Mortgage to "Exhibit A", "attached Exhibit
A" or "Exhibit A hereto" shall mean Exhibit A to the Mortgage, as supplemented
by Exhibit A-1 attached to this Amendment, and as the same may from time to
time be further amended or supplemented and "Hydrocarbon Property", as defined
in Section I(a) of the Mortgage, shall be deemed to include those oil and gas
leases and/or oil, gas and other mineral leases and other interests and estates
and the lands and premises covered or affected thereby which are described on
Exhibit A-1 attached to this Amendment.

       4.     Section II(a)(i) and Section II(b) of the Mortgage are hereby
amended to read as follows:

              "(i)   Payment of and performance of any and all indebtedness,
       obligations and liabilities of Mortgagor pursuant to the Second Amended
       and Restated Credit Agreement dated as of October 15, 1997 among
       Mortgagor, Mortgagee and the Lenders (such Credit Agreement together
       with all amendments thereto called the "CREDIT AGREEMENT"), including
       without limitation, those certain promissory notes which are or may be
       executed by Mortgagor in the aggregate principal amount of $250,000,000
       with final maturity on or before October 15, 2000 and all other notes
       given in substitution therefor or in modification, renewal or extension
       thereof, in whole or in part (such notes, as from time to time
       supplemented, amended or modified and all other notes given in
       substitution therefor or in modification, renewal or extension thereof,
       in whole or in part, being hereafter called the "NOTES")."

              "(b)   It is contemplated and acknowledged that the Indebtedness
       may include revolving credit loans and advances from time to time, and
       that this Mortgage shall have effect as of the date hereof to secure all
       Indebtedness, regardless of whether any amounts are advanced on the date
       hereof or on a later date or, whether having been advanced, are later
       repaid in part or in whole and further advances made at a later date.
       This Mortgage secures all future advances and obligations constituting
       Indebtedness.  The total amount of obligations and advances secured
       hereby may decrease or increase from time to time, but at no time shall
       the total amount of obligations and advances secured hereby exceed the
       sum of $250,000,000.00"

       5.     Mortgagor hereby confirms that it has heretofore mortgaged,
affected, pledged and hypothecated, and granted a security interest to
Mortgagee in, the Mortgaged Property; and Mortgagor further mortgages, affects,
pledges and hypothecates and grants a security interest to Mortgagee in, the
Mortgaged Property as supplemented by Exhibit A-1 attached hereto, to Mortgagee
on its behalf and on behalf of the Lenders to secure the payment and
performance of the Indebtedness, as amended hereby.

       6.     Mortgagor hereby confirms that it has heretofore absolutely and
unconditionally assigned, transferred and conveyed and does hereby absolutely
and unconditionally assign, transfer and convey to Mortgagee, its successors
and assigns, all of the Hydrocarbons and all products obtained or processed
therefrom attributable to the Hydrocarbon Property, and the revenues and
proceeds now and hereafter attributable to the Hydrocarbons and said products
and all payments in lieu of the Hydrocarbons such as "take or pay" payments or
settlements, all in accordance with Section V of the Mortgage as amended by
this Amendment.

       7.     Mortgagor hereby confirms and acknowledges that the Credit
Agreement constitutes a modification, renewal and extension of its liabilities
and debts represented by the Prior Credit Agreement.





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Mortgagor acknowledges and confirms that the Credit Agreement does not
constitute or effect a novation of the Prior Credit Agreement.

       8.     The parties hereto hereby acknowledge and agree that except as
specifically amended, changed or modified hereby, the Mortgage shall remain in
full force and effect in accordance with its terms.  None of the rights, titles
and interests existing and to exist under the Mortgage are hereby released,
diminished or impaired, and Mortgagor hereby reaffirms all covenants,
representations and warranties made in the Mortgage.

       9.     This Amendment may be executed in two or more counterparts, and
it shall not be necessary that the signatures of all parties hereto be
contained on any one counterpart hereof.


                          [SIGNATURES BEGIN NEXT PAGE]





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       THUS DONE AND PASSED this ___ day of October, 1997 to be effective on
and as of the 15th day of October, 1997 (the "EFFECTIVE DATE") in my presence
and in the presence of the undersigned witnesses who hereunto sign their names
with Mortgagor and me, Notary, after reading of the whole.



                                           MORTGAGOR:

WITNESSES:                                 OCEAN ENERGY, INC.



                                           By:                                 
-----------------------------                 ---------------------------------
Name:                                             Robert L. Belk
                                                  Executive Vice President and
                                                  Chief Financial Officer
-----------------------------                                            
Name:                         
                                           ATTEST:



                                           By:                                 
                                              ---------------------------------
[SEAL]                                            Robert K. Reeves
                                                  Secretary



                     -----------------------------------
                          Notary Public in and for the
                                 State of Texas

                             My Commission expires:


                     -----------------------------------





                                       4
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       THUS DONE AND PASSED this ___ day of October, 1997 to be effective on
and as of the 15th day of October, 1997 (the "EFFECTIVE DATE") in my presence
and in the presence of the undersigned witnesses who hereunto sign their names
with Mortgagee and me, Notary, after reading of the whole.

                                           MORTGAGEE:

WITNESSES:                                 THE CHASE MANHATTAN BANK



                                           By:                                 
-----------------------------                 ---------------------------------
Name:                                             Robert L. Belk
                                                  Executive Vice President and
                                                  Chief Financial Officer
-----------------------------                                            
Name:                         
                                           ATTEST:



                                           By:                                 
                                              ---------------------------------
[SEAL]                                            Robert K. Reeves
                                                  Secretary



                     -----------------------------------
                          Notary Public in and for the
                                 State of Texas

                             My Commission expires:


                     -----------------------------------





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