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                                                                   EXHIBIT 10.11

 
                               OMNI GEOPHYSICAL, L.L.C.
                                         AND
                                     DAVID CRAYS


                                   OPTION AGREEMENT


               THIS OPTION AGREEMENT (the "Option Agreement"or the "Agreement")
          is made and entered into on the 24th day of April, 1997 by and between
          OMNI GEOPHYSICAL, L.L.C., a Louisiana limited liability company
          ("Omni"), and DAVID CRAYS ("Crays").

                                 W I T N E S S E T H:

               WHEREAS, Omni desires to employ Crays as a Vice President and its
          Chief Financial Officer; and

               WHEREAS, in order to attract and retain Crays as its Chief
          Financial Officer, Omni is willing to grant Crays options to acquire
          516 of its Common Units upon the terms and conditions described
          herein.

               NOW, THEREFORE, in consideration of the mutual covenants set
          forth herein and for other good and valuable consideration, the
          receipt and legal sufficiency of which is hereby acknowledged, Crays
          and Omni hereby promise, covenant and agree as follows:

               1.   GRANT OF OPTION. Omni hereby irrevocably grants to Crays the
          right and option (the "Option") to purchase 516 of its Common Units
          (the "Common Units") on the terms and conditions herein set forth. As
          of the date of this Agreement, there are 103,263 Common Units
          outstanding.

               2.   OPTION PRICE. The purchase price for each Common Unit
          subject to the Option shall be Two Hundred Forty-Two and 25/100
          Dollars ($242.25) per Common Unit.

               3.   TERM OF OPTION; TRANSFERABILITY. The term of the Option
          shall be from the date of this Agreement through and including April
          30, 2007. The right to purchase Common Units under the Option shall
          vest and become effective as described in Section 5 of this Option
          Agreement. Crays shall not have any rights of a member of Omni with
          respect to the Common Units subject to this Option until the option is
          exercised and the sale of the Common Units subject to the Option is
          closed as provided herein. The Option and all of Crays' rights herein
          are nontransferable. The Option and the right to acquire Common Units
          pursuant to the Option shall be completely forfeited if Crays attempts
          or actually transfers, or otherwise disposes of the Option in
          contravention of Section 8 of this Option Agreement.

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               4.   METHOD OF EXERCISING OPTION. Subject to the terms and
          conditions of this Agreement, the Option may be exercised by written
          notice to Omni, at P.O. Box 3761, Lafayette, Louisiana 70502. Such
          written notice shall state the election of Crays to exercise the
          Option, shall set forth the number of Common Units he wishes to
          purchase pursuant to the Option and shall be considered to be given by
          Crays for purposes of this Option Agreement when such notice is
          deposited in the United States mail, certified mail, return receipt
          requested, with postage prepaid, to the address described above. Such
          written notice shall fix a closing date which is not more than thirty
          (30) days from the date such notice shall be given by Crays for the
          payment of the full purchase price of any Common Units being acquired
          pursuant to the exercise of the Option at a closing of the transaction
          at Omni's principal offices at that time. Payment of such purchase
          price shall be made by cashier's check or certified check payable to
          the order of Omni or in immediately available funds. At the closing of
          the transaction, Omni agrees to execute and, if deemed necessary by
          Omni's counsel, to cause each of its members to execute, an amendment
          to its Operating Agreement in order to effect the transfer of the
          acquired Common Units to Crays.

               5.   VESTING. The Options shall vest and become fully earned and
          nonforfeitable during the period commencing with the date of this
          Option Agreement and ending on the third (3rd) anniversary of the date
          of this Agreement (the "Vesting Period") as described in this Section
          5. Notwithstanding any other provision of this Agreement, unless Crays
          should remain in the continuous employ of Omni during the Vesting
          Period, then the Option shall be forfeited, and Crays' right to
          acquire Common Units under the Option shall be null and void except to
          the extent that such rights under the Option have vested as provided
          in this Section 5.

                    (a)  If Crays ceases to be employed within the first year of
          the Vesting Period, none of his rights under the Option shall be
          vested, and he shall have no right to acquire Common Units of Omni;

                    (b)  If Crays ceases to be employed within the second year
          of the Vesting Period (the period after the first anniversary but
          prior to the second anniversary of this Option Agreement), one-third
          of his rights under the Option shall be vested, and he shall have the
          right to acquire 172 Common Units of Omni;

                    (c)  If Crays ceases to be employed within the third year of
          the Vesting Period (the period after the second anniversary but prior
          to the third anniversary of this Option Agreement), two-thirds of his
          rights under the Option shall be vested, and he shall have the right
          to acquire an additional 172 Common Units of Omni, for a total of 344
          Common Units of Omni;

                    (d)  If Crays remains in the continuous employ of the
          Company from the date of this Option Agreement through the end of the
          Vesting Period, all of his rights under the Option shall be vested,
          and he shall have the right to acquire an additional 172 Common Units
          of Omni, for a total of 516 Common Units of Omni.

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                    (e)  If Crays' employment is terminated during the Vesting
          Period (i) by Omni without Cause or (ii) by Crays for Good Reason, as
          the terms "Cause" and "Good Reason", as applicable, are defined in the
          Employment Agreement dated of even date herewith between Omni and
          Crays (the "Employment Agreement"), the Option shall become
          immediately exercisable in full for a period of one year after
          termination of employment, after which time period the Option shall
          terminate.

                    (f)  If there is a change in control of Omni, as "Change in
          Control of the Company" is defined in the Employment Agreement, the
          Option shall become immediately exercisable in full for a period of
          one year after termination of employment, after which time period the
          Option shall terminate.

               6.   RIGHTS RELATED TO OPTION. The Option constitutes the right
          to acquire Common Units of Omni, as such Common Units are more fully
          described in Omni's Operating Agreement, or any security, instrument,
          property, or amount of consideration into which Common Units of Omni
          may be exchanged by reason of any merger, consolidation,
          recapitalization, reorganization or other transaction. The Option does
          not currently constitute equity in Omni, and Crays shall not be
          entitled to vote with the members of Omni on matters on which the
          members are entitled to vote as a result of the grant of the Option
          until such time as the Option is exercised and Crays acquires Common
          Units.

               7.   DUE AUTHORIZATION. The sale of Common Units of Omni pursuant
          to the exercise of this Option Agreement has been duly authorized by
          all necessary action of Omni. All members of Omni have consented to
          the issuance of any Common Units pursuant to the exercise of the
          Option, which consent shall be considered to be a consent for all
          purposes of Section 7 of the Omni Operating Agreement.

               8.   RESTRICTION ON TRANSFERABILITY OF OPTION. The Option is not
          assignable. Crays shall not transfer, convey, sell, assign, dispose
          of, pledge or otherwise convey the Option or any rights thereunder
          other than transfers by will or the laws of descent and distribution.
          Any such attempted disposition shall cause an immediate cancellation
          of the Option and forfeiture of any and all rights to acquire Common
          Units under the Option.

               9.   RESTRICTION ON TRANSFERABILITY OF COMMON UNITS. Both during
          and after the Vesting Period, the Common Units acquired as a result of
          exercise of the Option shall be subject to all transfer, admission and
          other restrictions and conditions contained in Omni's Operating
          Agreement. Any certificate representing Common Units shall bear a
          legend setting forth the restrictions on transfer contained in Omni's
          Operating Agreement. Crays shall not transfer, convey, sell, assign,
          dispose of, pledge or otherwise convey any Common Units acquired as a
          result of exercise of the Option except as provided in Omni's
          Operating Agreement. Any transferee of the Common Units shall agree to
          be bound by the terms and conditions of Omni's Operating Agreement.
          Any attempted disposition of the Common Units in contravention of this
          section shall be null and void.

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               10.  RESTRICTION ON TRANSFERABILITY RELATED TO SECURITIES LAW.
          Omni shall have the right to restrict any transfer of the Option or
          the Common Units acquired as a result of exercise of the Option during
          any such period as may be necessary or advisable to comply with the
          Securities Exchange Act of 1934, as amended. Neither the Option nor
          the Common Units acquired as a result of exercise of the Option have
          been nor will be registered under the Securities Act of 1933, and
          Crays shall not transfer, convey, sell, assign, dispose of, pledge or
          otherwise convey the Option or any Common Units acquired as a result
          of exercise of the Option unless (i) such Option or Common Units have
          been registered under the Act or (ii) an exemption from the
          registration provisions of the Act is applicable to Crays' proposed
          sale, assignment, pledge, disposition or transfer of such Option or
          Common Units.

               11.  BINDING EFFECT. This Agreement shall be binding upon and
          inure to the benefit of the parties hereto and their respective heirs,
          legal representatives, successors and assigns.

               12.  HEADINGS. The headings contained in this Agreement are for
          reference purposes only and shall not in any way affect the meaning or
          interpretation hereof.

               13.  APPLICABLE LAW. This Agreement shall be construed,
          interpreted and enforced under and in accordance with the internal
          laws of the State of Louisiana.

               14.  ADDITIONAL ACTS. The parties hereto agree, one to the other,
          that they will each, at any time and from time to time upon the
          request of the other party, do, perform, execute, acknowledge and
          deliver all such acts, deeds, assignments, transfers, conveyances,
          powers of attorney, certificates and assurances as may be reasonably
          required to consummate the transactions contemplated hereby.

               15.  NO WAIVERS OR MODIFICATION. No waivers or modifications of
          any provisions of this Agreement shall be valid or binding unless in
          writing and executed by all of the parties hereto.

               16.  MULTIPLE COUNTERPARTS. This Agreement may be executed in
          multiple counterparts and all counterparts shall be considered to be
          an original and enforceable as such.

               17.  ENTIRE AGREEMENT. This Agreement embodies the entire
          agreement between the parties and supersedes all prior agreements,
          warranties, representations and understandings, if any, relating to
          the option and may be amended or supplemented only by an instrument in
          writing executed by the party against whom the enforcement is sought.

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               IN WITNESS WHEREOF, Omni and Crays have executed this Option
          Agreement as of the day and year first above written.

                                   OMNI GEOPHYSICAL, L.L.C.



                                   By:/s/ Roger E. Thomas
                                      --------------------------------------
                                      Roger  E. Thomas, President



                                   /s/ David Crays
                                   -----------------------------------------
                                   David Crays


          

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