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                                                                    EXHIBIT 10.6



                              ASSUMPTION AGREEMENT


              ASSUMPTION AGREEMENT (this "Agreement") made and entered into
this 2nd day of July, 1997 by OCEAN ENERGY, INC., a Louisiana corporation ("OEI
Louisiana"), in favor of OCEAN ENERGY, INC., a Delaware corporation (the
"Company").

              WHEREAS, pursuant to an Indenture dated as of July 2, 1997 by and
among the Company, OEI Louisiana (as Subsidiary Guarantor) and State Street
Bank and Trust Company, as Trustee (the "Indenture"), the Company issued
$200,000,000 of its 8 7/8% Senior Subordinated Notes due 2007  (the "Notes");
and

              WHEREAS, substantially all of the net proceeds from the issuance
of the Notes are being transferred by the Company to OEI Louisiana to be used
in its business;

              NOW, THEREFORE, in consideration of such transfer of net proceeds
and for other good and valuable consideration, the receipt and sufficiency of
which are acknowledged, OEI Louisiana hereby agrees as follows:

              1.     Subject to the conditions and limitations hereinafter set
forth, OEI Louisiana hereby assumes and agrees to perform, pay and discharge,
as a primary obligor, all duties, obligations, debts and liabilities of the
Company in respect of the $200,000,000 Notes initially issued pursuant to the
Indenture (the "Assumed Obligation").

              2.     Each of OEI Louisiana and the Company acknowledge and
agree that (i) nothing contained in this Agreement shall modify or impair the
rights and obligations of the Company under either the Notes or the Indenture,
(ii) the Company shall remain liable for all such Assumed Obligations as a co-
obligor and (iii) this Agreement shall not modify or impair any obligation or
rights of OEI Louisiana under any Subsidiary Guarantee (as defined in the
Indenture) executed and delivered by OEI Louisiana in accordance with the
Indenture.

              3.     Anything in this Agreement or elsewhere to the contrary
notwithstanding, in no event shall OEI Louisiana be required to assume, or be
deemed to have assumed, any duties, obligations, debts or liabilities of the
Company other than the Assumed Obligations.

              4.     The obligations of OEI Louisiana under this Agreement are
limited to the maximum amount as will, after giving effect to all other
contingent and fixed liabilities of OEI Louisiana (including without limitation
any liabilities and obligations under any Subsidiary Guarantee) and after
giving effect to any collections from or payments made by or on behalf of any
other Subsidiary Guarantor (as such term is defined in the Indenture) in
respect of the obligations of such other Subsidiary Guarantor under its
Subsidiary Guarantee or pursuant to its contribution obligations under the
Indenture, result in the obligations of OEI Louisiana under this Agreement not
constituting a fraudulent conveyance or fraudulent transfer.
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              5.     This Agreement shall be binding upon OEI Louisiana and its
successors and assigns and inure solely to the benefit of the Company and its
successors and assigns.

              6.     This Agreement shall terminate, and the assumptions by OEI
Louisiana of the Assumed Obligations shall cease to be effective whereupon such
obligations shall remain the obligations of the Company, upon the full and
final discharge or release of OEI Louisiana of its obligations under its
Subsidiary Guarantee.

              7.     No stockholder, officer, director or incorporator, as
such, past, present or future, of the Company or of OEI Louisiana shall have
any personal liability under this Agreement by reason of his or its status as
such stockholder, officer, director or incorporator.

              8.     This Agreement shall be governed by and construed in
accordance with the law of the State of New York, without regard to principles
of conflicts of laws.

              IN WITNESS WHEREOF, OEI Louisiana and the Company have executed
this Agreement as of the date first above written.


                                                  OCEAN ENERGY, INC.,
                                                  a Louisiana corporation



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

                                                  OCEAN ENERGY, INC.,
                                                  a Delaware corporation



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





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