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                                                                   EXHIBIT 10.26

              AMENDMENT NUMBER THREE TO AGREEMENT FOR PURCHASE AND
                   ASSIGNMENT OF FOREIGN ACCOUNTS RECEIVABLE


         THIS AMENDMENT NUMBER THREE TO AGREEMENT FOR PURCHASE AND ASSIGNMENT OF
FOREIGN ACCOUNTS RECEIVABLE (this "Amendment"), dated effective as of March 5,
2002, is entered into by and between Grant Geophysical (Int'l), Inc., a Texas
corporation ("Grant"), and Elliott Associates, L.P., a Delaware Limited
Partnership ("Elliott"), as follows:

         WHEREAS, Grant and Elliott are parties to that certain Agreement for
Purchase of Foreign Accounts Receivable dated August 3, 2001 ( "Agreement").

         WHEREAS, Grant has requested that certain provisions of the Agreement
be amended, so as to provide for:

                  a)  an increase in the maximum amount purchased by Elliott
                      from Grant of billed and unbilled foreign accounts
                      receivable up to $10,900,000; and;

                  b)  an extension of the term of the Agreement to September 30,
                      2002.

                  c)  the parties agree that during the term of this Agreement
                      the loan balance may exceed the billed and unbilled
                      foreign accounts receivable collateral balance.

         WHEREAS, subject to the conditions set forth in this Amendment, Grant
and Elliott have agreed to amend the Agreement as set forth below:

         NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants, conditions, and provisions as hereinafter set forth, the parties
hereto agree as follows:

         1. AMENDMENT OF SUB-PARAGRAPH 2 IN THE PREAMBLE OF THE AGREEMENT. The
Preamble of the Agreement is hereby amended to read in its entirety as follows:

         "WHEREAS, Elliott agrees to purchase from Grant up to a maximum of Ten
Million Nine Hundred Thousand USD ($10,900,000), at any point in time,
commencing August 3, 2001 and extending through September 30, 2002;" and;

         2. AMENDMENT OF SECTION 1. OFFER OF ACCOUNTS IN THE AGREEMENT. Section
         1 of the Amendment No. 2 dated February 5, 2002 is hereby amended by
         substitution of "Ten Million Nine Hundred Thousand USD ($10,900,000)"
         for "Seven Million Five Hundred Thousand USD ($7,500,000)".
         Furthermore, Section 1 of the Agreement is hereby amended and the
         following inserted at the end of the paragraph.
                           "The parties agree that during the term of this
                           Agreement the loan balance may exceed the billed and
                           unbilled foreign accounts receivable collateral
                           balance."


         3. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations and
warranties made herein and in the Agreement shall survive the execution and
delivery of this


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Amendment, and no investigation by Elliott or any closing shall affect the
representations and warranties or the right of Elliott to rely upon them.

         4. REFERENCE TO AGREEMENT. The Agreement, as amended hereby, and all
other Exhibits thereto, whether now or hereafter executed and delivered, are
hereby amended so that any reference to the Agreement shall mean a reference to
the Agreement, as amended by this Amendment.

         5. SEVERABILITY. Any provision of this Amendment held by a court of
competent jurisdiction to be invalid or unenforceable shall not impair or
invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

         6. SUCCESSORS AND ASSIGNS. This Amendment is binding upon and shall
inure to the benefit of Elliott and Grant and their respective successors and
assigns, except Grant may not assign or transfer any of its rights or
obligations hereunder without the prior written consent of Elliott.

         7. COUNTERPARTS. This Amendment may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original,
but all of which when taken together shall constitute one and the same
instrument.

         8. FACSIMILE TRANSMISSION OF SIGNATURES. Any party to this Amendment
may indicate its intention to be bound by its execution and delivery of this
Amendment by its signature to the signature page hereof and the delivery of the
signature page hereof, to the other party or its representatives by facsimile
transmission or telecopy. The delivery of a party's signature on the signature
page by facsimile transmission or telecopy shall have the same force and effect
as if such party signed and delivered this Amendment in person.

IN WITNESS WHEREOF, the parties hereto, heretofore duly authorized, have
executed this Agreement to be effective as of the date first set forth above.

Address for Notices:                GRANT GEOPHYSICAL, (INT'L.) INC.

16850 Park Row
Houston, Texas  77084               by: /s/ WILLIAM H. FREEMAN
Fax:  (281) 398-9996                   -----------------------------------------
                                    Name:   William H. Freeman
                                    Title:  Treasurer


Address for Notices:                ELLIOTT ASSOCIATES, L.P.

712 Fifth Avenue
New York, NY 10019                  by: /s/ JON POLLOCK
Fax:  (212) 586-9428                   -----------------------------------------
                                    Name:   Jon Pollock
                                    Title:  Sr. Portfolio Manager