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                               SECURITY AGREEMENT                   EXHIBIT 10.2

                                                                    July 1, 1997


                 I.  Parties, Collateral, and Obligations

                 FRANK A. PICI (hereinafter called "Debtor"), whose address is
6306 Wagner Way, Sugar Land, Texas 77479, for valuable considerations, receipt
of which is hereby acknowledged, hereby grants to MARINER ENERGY, INC., a
Delaware corporation (hereinafter called "Secured Party"), whose address is a
580 Westlake Boulevard, Suite 1300, Houston, Harris County, Texas 77079, a
security interest in the following property:

         (i) all shares of capital stock of Mariner Holdings, Inc., a Delaware
         corporation ("MHI"), now owned or hereafter acquired by Debtor
         (including, but not limited to, all shares of MHI capital stock
         acquired by Debtor with the proceeds of the Note (as hereinafter
         defined) and all shares of MHI capital stock acquired by Debtor upon
         the exercise of any stock options granted by MHI to Debtor); (ii) all
         of Debtor's rights and interests in and under that certain Incentive
         Stock Option Agreement dated July 1, 1997, between MHI and Debtor;
         (iii) all of Debtor's rights and interests in and under that certain
         Nonstatutory Stock Option Agreement dated July 1, 1997, between MHI
         and Debtor; (iv) all of Debtor's rights and interests, whether now
         existing or hereafter acquired or arising, to acquire any share of
         capital stock of MHI (including, but not limited to, any rights of
         Debtor under any future stock option agreements, stock option plans
         and stock incentive or compensation plans or agreements); and (v) all
         of Debtor's rights, title and interests in or in respect of, whether
         now existing or hereafter acquired or arising in, any "Overriding
         Royalty Interest," as such term is defined from time to time in that
         certain Employment Agreement dated effective as of December 2, 1996,
         as amended from time to time (the "Employment Agreement"), between
         Secured Party and Debtor, and in any contractual or other rights to
         acquire or obtain, or in respect of, any such Overriding Royalty
         Interest;

together with all proceeds, monies, income, investment property, revenues,
royalties, funds and benefits attributable or accruing to said property, which
Debtor is or may hereafter become entitled to receive on account of said
property, including, but not by way of limitation, all interest, premium,
redemption proceeds and other principal payments and all dividends and other
distributions on or with respect to capital stock whether payable in cash,
stock or other property and all subscription and other rights.  In the event
that Debtor shall receive any of the foregoing, Debtor shall receive and

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hold the same in trust for Secured Party and shall not commingle the same with
other monies or property, and Debtor shall promptly and immediately deliver
same to Secured Party.  All property in which Secured Party is herein granted a
security interest is hereinafter called the "Collateral."

                 The security interest granted herein secures the payment of
all liabilities, indebtedness, and obligations of Debtor to Secured Party
(hereinafter called the "Obligations") arising under and evidenced by a
promissory note of even date herewith (hereafter called the "Note") executed by
Debtor in the principal amount of $170,600.00, payable to the order of Secured
Party, and including costs and expenses and attorney's fees and legal expenses,
all in accordance with the terms of the Note and this Security Agreement, and
all renewals, extensions and rearrangements of the above Obligations.  Unless
otherwise agreed, all of the Obligations shall be payable at the offices of
Secured Party in Houston, Harris County, Texas.

                 II.      Warranties, Covenants and Agreements of the Debtor

                 Debtor hereby warrants, covenants and agrees that:

                 (1)      Except for the security interest granted hereby,
Debtor is the owner and holder of all the Collateral free from any adverse
claim, security interest, encumbrance, lien, charge or any other right, title,
or interest of any person other than Secured Party; Debtor has full power and
lawful authority to sell, transfer and assign the Collateral to Secured Party
and to grant to the Secured Party a first, prior and valid security interest
therein as herein provided; the execution and delivery and the performance
hereof are not in contravention of any indenture, agreement or undertaking to
which the Debtor is a party or by which the Debtor is bound.

                 (2)(a)   Debtor has not heretofore signed any financing
statement or security agreement which covers any of the Collateral, and no such
financing statement or security agreement is now on file in any public office.

                 (b)      As long as any amount remains unpaid on any of the
Obligations, (i) Debtor will not enter into or execute any security agreement
or any financing statement which covers any of the Collateral other than those
security agreements and financing statements in favor of Secured Party
hereunder, and further (ii) there will not be on file in any public office any
financing statement or statements (or any documents or papers filed as such)
which covers any of the Collateral other than financing statements in favor of
Secured Party hereunder.

                 (c)      Debtor authorizes Secured Party to file, in
jurisdictions where this authorization will be given effect, a financing
statement signed only by Secured Party covering the Collateral.  At the request
of Secured Party, Debtor will join Secured Party in executing such documents as
Secured Party may determine, from time to time, to be





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necessary or desirable under provisions of the Uniform Commercial Code; without
limiting the generality of the foregoing, Debtor agrees to join Secured Party,
at Secured Party's request, in executing one or more financing statements in
form satisfactory to Secured Party, and Debtor will pay the cost of filing or
recording the same, or of filing or recording this Security Agreement, in all
public offices at any time and from time to time, whenever filing or recording
of any such financing statement or of this Security Agreement is deemed by
Secured Party to be necessary or desirable.  In connection with the foregoing,
it is agreed and understood between the parties hereto (and Secured Party is
hereby authorized to carry out and implement the following agreements and
understandings and Debtor hereby agrees to pay the cost thereof) that Secured
Party may, at any time or times, file as a financing statement any counterpart,
copy, or reproduction of this Security Agreement signed by Debtor if Secured
Party shall elect so to file, and it is also agreed and understood that Secured
Party may, if deemed necessary or desirable, file (or sign and file) as a
financing statement any carbon copy of, or photographic or other reproduction
of, this Security Agreement or of any financing statement executed in
connection with this Security Agreement.

                 (3)      Debtor will not sell or offer to sell or otherwise
transfer or encumber the Collateral or any interest therein without the written
consent of Secured Party; and Debtor will keep the Collateral free from any
adverse, lien, security interest, encumbrance, charges or claim.

                 (4)      Except as specifically otherwise permitted or
provided herein, if, at any time, the Debtor holds or has possession of the
Collateral or any part thereof, or of any other goods, documents or instruments
now or at any time constituting a part of the Collateral subject to this
Security Agreement, then the same shall remain in Debtor's possession and
control at all times at Debtor's risk of loss, and, if in Debtor's possession,
are now kept, and at all times shall be kept, at the address given in the blank
below:


or if left blank at the address first shown for Debtor at the beginning of this
Security Agreement; and in any event Debtor will promptly notify Secured Party
of any change in any of such addresses and of any new addresses where the
Collateral or any such goods, documents or instruments are or may be kept and
of any other change in the above-identified location of all or any part of the
Collateral, and Debtor will not move or remove the Collateral or such goods,
documents, or instruments, or any part thereof, from the addresses and places
described and specified above without the prior written consent of Secured
Party.

                 (5)      All information supplied and statements made by
Debtor in any financial, credit or accounting statement or application for
credit made or delivered to Secured Party by or on behalf of Debtor prior to,
contemporaneously with or




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subsequent to the execution of this Security Agreement are and shall be true,
correct, complete, valid and genuine.

                 (6)      Debtor will, upon the execution of this Security
Agreement by Debtor, deliver, or cause to be delivered, to Secured Party the
instruments, securities, documents, and chattel paper subject to this Security
Agreement; furthermore, if any instruments, securities, chattel paper, money or
monies, or documents are, at any time or times, included in the Collateral,
whether as proceeds or otherwise, Debtor will promptly deliver the same to
Secured Party upon the receipt thereof by Debtor, and in any event promptly
upon demand therefor by Secured Party.  Notwithstanding anything contained in
the Employment Agreement to the contrary, as a condition precedent to Secured
Party's obligations to deliver to Debtor any recordable assignment of any
Overriding Royalty Interest, Debtor shall execute and deliver to Secured Party
in recordable form and otherwise in form and substance satisfactory to Secured
Party a mortgage, assignment of production and security agreement, and/or such
other instruments and/or documents as Secured Party shall determine, covering
such Overriding Royalty Interest and securing payment of the Obligations.

                 III.     Events of Default

                 Debtor shall be in default under this Security Agreement upon
the happening of any of the following events or conditions (each an "Event of
Default"):

                 (1)      Default in the payment when due of the principal of,
or interest on, the Note or of any other of the Obligations;

                 (2)      Default in the performance of any agreement or
obligation of Debtor to the holder of the Obligations;

                 (3)      Any warranty, representation or statement made in
this Security Agreement or made or furnished to Secured Party by or on behalf
of Debtor in connection with this Security Agreement or to induce Secured Party
to make any loan to Debtor proves to have been false in any material respect
when made or furnished; or any financial statement of Debtor or of any
endorser, guarantor or surety on any of the Obligations which has been or may
be furnished to Secured Party by or on behalf of Debtor or such guarantor,
endorser or surety shall prove to be false in any materially detrimental
respect;

                 (4)      The levy of any attachment, execution, or other
process against Debtor or any of the Collateral;

                 (5)      Death, insolvency or business failure of Debtor, or
the commission of any act of bankruptcy by, or the appointment of receiver or
other legal representative for any part of the property of, assignment for the
benefit of creditors by, or the




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commencement of any proceedings under any bankruptcy or insolvency law by or
against, Debtor;

                 (6)      Failure or refusal of Debtor to perform or observe
any of the covenants, duties or agreements herein imposed upon or agreed to be
performed or observed by Debtor;

                 (7)      The occurrence of any "Event of Default" as such term
is defined in the Note.

                 IV.      Remedies

                 (1)      In the event of the default in the payment of any of
the Obligations or any principal, interest or other amount payable thereunder,
when due, or upon the happening of any of the Events of Default specified
above, and at any time thereafter, at the option of the holder thereof, any or
all of the Obligations shall become immediately due and payable without
presentment or demand or any notice to the Debtor or any other person obligated
thereon and Secured Party shall have and may exercise with reference to the
Collateral and Obligations any or all of the rights and remedies of a secured
party under the Uniform Commercial Code as adopted and as amended in the State
of Texas, and as otherwise granted herein or under any other law or under any
other agreement executed by Debtor, including, without limitation, the right
and power to sell, at public or private sale or sales, or otherwise dispose of
or utilize the Collateral and any part or parts thereof in any manner
authorized or permitted under said Uniform Commercial Code after default by a
debtor, and to apply the proceeds thereof toward payment of any costs and
expenses and attorney's fees and legal expenses thereby incurred by Secured
Party and toward payment of the Obligations in such order or manner as Secured
Party may elect.  To the extent permitted by law, Debtor expressly waives any
notice of sale or other disposition of the Collateral and any other rights or
remedies of Debtor or formalities prescribed by law relative to sale or
disposition of the Collateral or exercise of any other right or remedy of
Secured Party existing after default hereunder; and to the extent any such
notice is required and cannot be waived, Debtor agrees that if such notice is
mailed, postage prepaid, to Debtor either at the street address first shown
hereinabove or at the mailing address, if any, shown for Debtor at the
beginning of this Security Agreement at least five days before the time of the
sale or disposition, such notice shall be deemed reasonable and shall fully
satisfy any requirement for giving of notice.

                 (2)      Secured Party is expressly granted the right, at its
option, to transfer at any time to itself or to its nominee the Collateral, or
any part thereof, and to receive the monies, income, proceeds or benefits
attributable or accruing thereto and to hold the same as security for the
Obligations or to apply the same on the principal and interest or other amounts
owing on any of the Obligations, whether or not then due, in such order or
manner as Secured Party may elect.  Secured Party is further




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expressly granted the rights, exercisable at its option at any time, whether
before or after default, to take control of any proceeds, payments, monies,
income, collections or benefits and to notify account debtors, lessees,
obligors on any instruments or other obligors to make all payments directly to
Secured Party on any and all accounts, leases, instruments, or obligations,
constituting, at any time or from time to time, a part of the Collateral and to
make payment directly to Secured Party of all such income, monies, proceeds or
other benefits; and Debtor will, upon request of Secured Party, so notify all
such account debtors, lessees or obligors.  Without limiting in any way the
generality of the preceding sentences, it is expressly acknowledged and agreed
by Debtor and Secured Party that Secured Party shall have the express right, at
its option, to receive directly any and all cash payable to Debtor on, or
otherwise in respect of, any Overriding Royalty Interest and apply such amounts
as received to the outstanding principal balance of the Obligations, whether or
not then due, without further consent or authorization from Debtor.

                 (3)      All recitals in any instrument of assignment or any
other instrument executed by Secured Party incident to sale, transfer,
assignment or other disposition or utilization of the Collateral or any part
thereof hereunder shall be full proof of the matters stated therein and no
other proof shall be requisite to establish full legal propriety of the sale or
other action taken by Secured Party or of any fact, condition or thing incident
thereto and all prerequisites of such sale or other action or of any fact,
condition or thing incident thereto shall be presumed conclusively to have been
performed or to have occurred.

                 (4)      All rights to marshalling of assets of Debtor,
including any such right with respect to the Collateral, are hereby waived by
Debtor.

                 (5)      The right of Secured Party to take possession or
control of the Collateral upon the happening of any of the events or conditions
constituting a default may be exercised without resort to any court proceeding
or judicial process whatever and without any hearing whatever thereon; and, in
this connection, DEBTOR EXPRESSLY WAIVES ANY CONSTITUTIONAL RIGHTS OF DEBTOR
WITH REGARD TO NOTICE, ANY JUDICIAL PROCESS OR ANY HEARING PRIOR TO THE
EXERCISE OF THE RIGHT OF SECURED PARTY TO TAKE POSSESSION OR CONTROL OF THE
COLLATERAL UPON THE HAPPENING OF ANY OF THE EVENTS OR CONDITIONS CONSTITUTING A
DEFAULT.

                 V.       General

                 (1)      Secured Party may, at its option, whether or not the
Obligations are due, demand, sue for, collect or make any compromise or
settlement it deems desirable with reference to the Collateral.  Secured Party
shall not be obligated to take any steps necessary to preserve any rights in
the Collateral against other parties, which Debtor hereby assumes to do.




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                 (2)      This Security Agreement shall not be construed as
relieving Debtor from full personal liability on the Obligations and any and
all future and other indebtedness secured hereby and for any deficiency
thereon.

                 (3)      If maturity of the Obligations shall be accelerated
for any reason, the full amount of any interest then unearned which has been
collected theretofore by or for Secured Party shall thereupon be credited
against the Obligations.  Notwithstanding any other provision in this Security
Agreement or in the Obligations or any of them, Debtor shall never be liable
for unearned interest on the Obligations, or on any of them, and shall further
never be required to pay interest on the Obligations, or on any of them, at a
rate in excess of the maximum percentage rate authorized and allowed by
applicable law.  The intent of the parties being to conform and comply fully
with all laws concerning usury applicable hereto or to the Obligations or any
part thereof, any agreement concerning interest in any of the foregoing shall
be subject to reduction to the amount allowed under the applicable laws with
respect to usury, as now or hereafter construed by the courts with jurisdiction
thereof, and any interest collected in excess of the amount authorized and
permitted by such laws shall be refunded to the person paying the same, or
credited against the Obligations.

                 (4)      No delay or omission on the part of Secured Party in
exercising any right hereunder shall operate as a waiver of any such right or
any other right.  A waiver on any one or more occasions shall not be construed
as a bar to or waiver of any right or remedy on any future occasion.

                 (5)      The execution and delivery of this Security Agreement
in no manner shall impair or affect any other security (by endorsement or
otherwise) for the payment of the Obligations and no security taken hereafter
as security for payment of any part or all of the Obligations shall impair in
any manner or affect this Security Agreement, all such present and future
additional security to be considered as cumulative security.  Any of the
Collateral may be released from this Security Agreement without altering,
varying or diminishing in any way the force, effect, lien, security interest,
or charge of this Security Agreement as to the Collateral not expressly
released, and this Security Agreement shall continue as a first lien, security
interest and charge on all of the Collateral not expressly released until all
sums and indebtedness secured hereby have been paid in full.  Any future
assignment or attempted assignment or transfer of the interest of Debtor in and
to any of the Collateral shall not deprive Secured Party of the right to sell
or otherwise dispose of or utilize all of the Collateral as above provided or
necessitate the sale or disposition thereof in parcels or in severalty.

                 (6)      Any notice or demand to Debtor hereunder or in
connection herewith may be given and shall conclusively be deemed and
considered to have been given and received upon the deposit thereof, in
writing, in the United States mails, duly stamped and addressed to Debtor
either at the street address first shown hereinabove




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or at the mailing address, if any, given for Debtor at the beginning of this
Security Agreement; but actual notice, however given or received, shall always
be effective.

                 (7)      All rights of Secured Party hereunder shall inure to
the benefit of its successors and assigns; and all obligations of Debtor shall
bind his heirs, executors, or administrators, and his or its successors or
assigns.  If there be more than one Debtor, their obligations hereunder shall
be joint and several.

                 (8)      Each term used in this Security Agreement, unless the
context otherwise requires, and in all events subject to any express
definitions set forth in this Security Agreement, shall be deemed to have the
same meaning herein as that given each such term under the Uniform Commercial
Code, as adopted and as amended in the State of Texas.


                 (9)      As used in this Security Agreement and when required
by the context, each number (singular and plural) shall include all numbers,
and each gender shall include all genders; and unless the context otherwise
requires, the word "person" shall include "corporation, firm or association."

                 (10)     The law governing this secured transaction shall be
that of the State of Texas existing as of the date hereof; provided, that if
any additional rights or remedies are granted by the law of Texas to secured
parties or to persons similarly situated to Secured Party, then Secured Party
shall also have and may exercise any such additional rights or remedies.
Signed in multiple original counterparts and delivered on the day and year
first above written.


                                                     /s/ FRANK A. PICI        
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                                                         Frank A. Pici



The  undersigned, Sharon Pici, is the spouse of Debtor and in such capacity
executes the Security Agreement for the purpose of binding any and all rights
(including spousal rights and community property rights) that she may have in
the Collateral.




                                                      /s/ SHARON PICI         
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                                                          Sharon Pici




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