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                                                                    EXHIBIT 10.6
 
                           OMNI GEOPHYSICAL, L.L.C.
                                      AND
                               ALLEN R. WOODARD

                   EMPLOYMENT AND NON-COMPETITION AGREEMENT


               THIS EMPLOYMENT AND NON-COMPETITION AGREEMENT is made and entered
          into as of the 19th day of July, 1996 (the "Agreement") by and between
          OMNI GEOPHYSICAL, L.L.C., a Louisiana limited liability company
          (hereinafter referred to as "Company") and ALLEN R. WOODARD, a
          resident of the State of Louisiana (hereinafter referred to as
          "Employee").

               WHEREAS, the Company is desirous of obtaining the services of the
          Employee upon the terms and conditions contained herein; and

               WHEREAS, the Employee is desirous of providing services for the
          Company upon the terms and conditions contained herein.

               NOW, THEREFORE, in consideration of the mutual promises,
          covenants and agreements herein contained, the receipt and legal
          sufficiency of which are hereby acknowledged, the parties hereto agree
          as follows:

               1.   EMPLOYMENT.  The Company hereby hires the Employee and the
          Employee hereby agrees to be employed upon the terms and conditions
          hereinafter set forth.

               2.   TERM.  Subject to the provisions for termination as
          hereinafter provided, the term of this Agreement shall be for a period
          of thirty-six (36) months.

               3.   COMPENSATION.  For the period beginning on the mutual
          execution of this Agreement and expiring on the termination of this
          Agreement, Company shall pay Employee One Hundred Thousand Dollars
          ($100,000) per annum.

               4.   DUTIES.  Employee shall serve as the Chief Operating Officer
          of the Company and as a member of the Company's Board of Directors.
          Notwithstanding anything in this Agreement to the contrary, Employee
          shall perform such other duties, tasks and other work as may be
          assigned to him by the Company's officers and Board of Directors.

               5.   TERMINATION.  This Agreement may be terminated at any time
          by the Company, without prior notice, for cause or for breach of any
          obligation of Employee to Company.

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               6.   CONFIDENTIALITY AND NON-DISCLOSURE OF INFORMATION.  Employee
          recognizes, acknowledges and agrees that the names of the Company's
          customers and its pricing structure, processes, operations, marketing
          programs, sales techniques, designs, specifications and other trade
          secrets (collectively referred to herein as "Proprietary Information")
          are valuable, special and unique assets of the Company. Employee will
          not, during or after the term of Employee's employment, directly or
          indirectly, utilize for the benefit of any person, business,
          enterprise or entity other than Company, or disclose any portion or
          part of the Company's Proprietary Information to any person, firm,
          corporation, association or other entity for any reason or purpose
          whatsoever. Furthermore, it is agreed that all data, lists, papers,
          memoranda, documents, and all products of Employee's skill, resulting
          from Employee's employment herein, shall be and remain the sole and
          exclusive property of the Company, and Employee shall execute any and
          all agreements and instruments that may be necessary to evidence the
          Company's ownership of such property. In the event of a breach or
          threatened breach by the Employee of the provisions of this Section 6,
          the Company shall be entitled to an injunction restraining the
          Employee from breaching the terms of this Agreement. Nothing herein
          shall be construed as prohibiting the Company from pursuing any other
          remedy available to the Company for such breach or threatened breach,
          including the recovery of damages from the Employee.

               7.   COVENANT OF NON-COMPETITION.  For a period during Employee's
          employment and ending five (5) years after termination of Employee's
          employment under this Agreement (whether such termination occurs
          because of a breach of this Agreement by the Company or by Employee or
          because of a termination of this Agreement by Company or Employee):
          (a) the Employee will not, directly or indirectly, within any parish
          or municipality in Louisiana or in any other state or foreign
          jurisdiction in which customers of the Company are located or reside,
          solicit, induce or otherwise contact customers of the Company for the
          purpose of soliciting business from the Company's customers, or any
          other purpose whatsoever which is detrimental to the Company or its
          business; (b) the Employee will not, directly or indirectly, within
          any parish or municipality in Louisiana or in any other state or
          foreign jurisdiction in which Company engages in or has engaged in
          business, own, manage, operate, control, be employed by, consult with,
          participate in, or be connected in any manner with the ownership,
          management, operation or control of any business, enterprise, or
          entity (including a sole proprietorship of Employee) which: (i) owns,
          operates or controls any geophysical services business, which business
          includes but is not limited to the provision of seismic drilling and
          support services, the transportation of equipment used in connection
          with seismic drilling and support services, and the design and
          manufacture of such equipment, or (ii) owns, operates or controls any
          business which competes with the Company. In the event of any actual
          or threatened breach by the Employee of the provisions of this
          Agreement, Employee agrees that Company shall not have an adequate
          remedy at law and the Company shall be entitled to an injunction
          restraining the Employee from owning, managing, operating,
          controlling, being employed by, participating in, or being in any way
          so connected with any activity which is prohibited in this Section 7
          and/or the solicitation of any business on his behalf or on behalf of
          others from any customer. Nothing herein stated shall be construed as
          prohibiting Company from pursuing any other remedies available to the
          Company for such breach or threatened breach including the recovery of
          damages from the Employee.

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               8.   PERMITTED BUSINESS.  The parties acknowledge that Employee
          has a fifty percent (50%) ownership interest in the stock of
          Birthright Investment Group, Inc. d/b/a Marsh Equipment Company, a
          Louisiana corporation ("Marsh Equipment"), which designs, manufactures
          and sells equipment that can be used to provide seismic drilling and
          support services. Notwithstanding the provisions of Section 7 of this
          Agreement, the Company acknowledges and agrees that Employee may
          continue to own the interest in Marsh Equipment set forth in this
          Section 8 without violating the non-competition restrictions and
          covenants contained in this Agreement.

               9.   COMPANY'S OPTION TO PURCHASE MARSH EQUIPMENT.  At any time
          during the term of this Agreement, the Company shall have the option
          to purchase all (but not less than all) of Employee's right, title and
          interest in and to the stock of Marsh Equipment for a purchase price
          of Twenty Thousand Dollars ($20,000) (the "Company's Option"). The
          Company's Option shall be exercisable by delivery of a written notice
          to the Employee. The closing date for the exercise of the Company's
          Option shall be as mutually agreed upon by the Company and the
          Employee, but shall not be later than thirty (30) days after delivery
          of the written notice referred to in this Section 9.

               10.  EMPLOYEE'S PUT OF MARSH EQUIPMENT.  At any time during the
          term of this Agreement, the Employee shall have the right to sell, and
          to require the Company to purchase all (but not less than all) of
          Employee's right, title and interest in and to the stock of Marsh
          Equipment for a purchase price of Twenty Thousand Dollars ($20,000)
          (the "Employee's Put"). The Employee's Put shall be exercisable by
          delivery of a written notice to the Company. The closing date for the
          exercise of the Employee's Put shall be as mutually agreed upon by the
          Company and the Employee, but shall not be later than thirty (30) days
          after delivery of the written notice referred to in this Section 10.

               11.  REFORMATION/SAVINGS CLAUSE.  The parties agree that if
          either the length of time or the geographical area of Employee's
          covenants contained herein are deemed too restrictive by any court of
          competent jurisdiction in any proceeding involving the validity of
          said covenants, then the court may reduce the offending restriction to
          the maximum restriction it deems reasonable under the circumstances so
          as to give the maximum permissible effect to the intentions of the
          parties as set forth herein, and the court may enforce such provisions
          as so reformed.

               12.  REMEDIES AND EQUITABLE PROVISIONS.  The following provisions
          shall apply in respect of Employee's covenants and agreements
          contained in this Agreement:

               (a)  Employee acknowledges and agrees that Employee's covenants
          contained in this Agreement are reasonable and necessary for the
          proper protection of Company and that the Employee's agreements herein
          not to compete with the Company shall not hinder Employee in obtaining
          gainful employment at the termination of this Agreement in the event
          Employee shall desire such employment.

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               (b)  Employee acknowledges and agrees that Company does not have
          an adequate remedy at law for the breach or threatened breach of
          Employee's covenants contained in this Agreement and Employee
          therefore agrees that Company, in addition to any other remedy which
          may be available to it, shall be entitled to enforce Employee's
          covenants by injunction or other equitable means.

               (c)  The parties agree that if Company should institute
          litigation against Employee to enforce any provisions of this
          Agreement, then the prevailing party in such litigation shall be
          entitled to receive, in addition to any other relief awarded such
          party, reasonable attorneys' fees in respect of the prosecution or
          defense of such litigation.

               13.  NOTICES.  Any notice required or permitted to be given under
          this Agreement shall be sufficient if in writing, and if sent by
          certified mail

               If to Employee:  Allen R. Woodard
                                1902 Sevanne Road
                                Houma, Louisiana 70360

               If to Company:   Omni Geophysical, L.L.C.
                                P.O. Box 3761
                                Lafayette, Louisiana 70502

               14.  WAIVER OF BREACH.  The waiver or nonenforcement by the
          Company of a breach of any provision of this Agreement by the Employee
          shall not operate or be construed as a waiver of any subsequent breach
          by the Employee.

               15.  ASSIGNMENT.  Employee acknowledges that the services to be
          rendered by him are unique and personal. Accordingly, Employee may not
          assign any of his rights or delegate any of his duties or obligations
          under this Agreement. The rights and obligations of Company under this
          Agreement shall inure to the benefit of and shall be binding upon the
          successors and assigns of Company.

               16.  SEVERABILITY.  Every provision of this Agreement is entitled
          to be severable. The parties agree that if any term or provision
          hereof is held to be illegal, invalid, against public policy or
          unenforceable for any reason whatsoever, such illegality or invalidity
          shall not affect the validity of the remainder to the Agreement, and
          the remaining provisions of this Agreement shall not be affected
          thereby.

               17.  AMENDMENTS.  No alterations, modifications, amendments or
          changes herein shall be effective or binding upon the parties unless
          the same shall have been agreed in writing by all the parties.

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               18.  SECTION HEADINGS.  Section and other headings in this
          Agreement are for reference purposes only, and are in no way intended
          to describe, interpret, define or limit the scope or extent of any
          provision hereof.

               19.  COUNTERPART EXECUTION.  This Agreement may be executed by
          any number of counterparts with the same effect as if all parties
          hereto had signed the same document. All counterparts shall be
          construed together and shall constitute one agreement.

               20.  APPLICABLE LAW.  Company and Employee acknowledge and agree
          that the law of several states could, conceivably, apply to the terms
          of this Agreement. In order to provide certainty with respect to the
          construction, interpretation and enforcement of this Agreement, it is
          the intention of the parties that the internal laws of the State of
          Louisiana shall govern only the construction, interpretation, validity
          and enforcement of each term of the Agreement which relates to
          obligations which are intended to be performed or restrictions upon
          the activities or conduct of the parties within the State of
          Louisiana. The construction, interpretation, validity and enforcement
          of each term of the Agreement which relates to obligations to be
          performed or restrictions upon the activities or conduct of the
          parties outside of the State of Louisiana shall be governed by the law
          of the State of Texas. The parties to this Agreement have agreed to
          this bifurcated choice of law after careful consideration and
          reflection.

               21.  RIGHTS CUMULATIVE.  The rights of Company hereunder shall be
          cumulative and the enforcement by Company of any right shall not
          affect in any way the ability of Company to enforce any other right
          hereunder or any right or remedy of Company at law or in equity.

               22.  ENTIRE AGREEMENT.  This instrument contains the entire
          agreement of the parties and may not be changed orally but only by
          agreement in writing signed by the party against whom enforcement of
          any waiver, change, modification or discharge is sought.


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               IN WITNESS WHEREOF, the Company has caused this Agreement to be
          executed by its duly authorized managers, and the Employee has
          hereunto set his hand as of the day and year first above written.

                                    COMPANY

                                    OMNI GEOPHYSICAL, L.L.C.,
                                    a Louisiana limited liability company


                                    By:/s/ David Jeansonne
                                       --------------------------------
                                           David Jeansonne, Manager


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


                                    EMPLOYEE



                                    /s/Allen R. Woodard
                                    -----------------------------------
                                       Allen R. Woodard


          

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