SECURITY AGREEMENT TO SECOND AMENDED AND RESTATED REVOLVING CREDIT AND SECURITY AGREEMENT

THIS SIXTH AMENDMENT TO SECOND AMENDED AND RESTATED REVOLVING CREDIT AND SECURITY AGREEMENT (this “ Amendment ”) is entered into as of February 11, 2009, by and among GEOKINETICS INC., a Delaware corporation (“ Geokinetics ”), GEOKINETICS PROCESSING, INC. (formerly known as GEOPHYSICAL DEVELOPMENT CORPORATION), a Texas corporation (“ Processing ”), GEOKINETICS USA, INC. (formerly known as QUANTUM GEOPHYSICAL, INC.), a Texas corporation (“ USA ”), GEOKINETICS EXPLORATION INC., an entity organized under the laws of Canada (“ Exploration ”), GEOKINETICS INTERNATIONAL HOLDINGS, INC. (formerly known as GRANT GEOPHYSICAL, INC.), a Delaware corporation (“ International Holdings ”), GEOKINETICS INTERNATIONAL, INC. (formerly known as GRANT GEOPHYSICAL (INT’L), INC.), a Texas corporation (“ International ”), GEOKINETICS MANAGEMENT, INC. (formerly known as GRANT GEOPHYSICAL CORP.), a Texas corporation (“ Management ”), GEOKINETICS SERVICES CORP., a Texas corporation (“ Geokinetics Services ”), and ADVANCED SEISMIC TECHNOLOGY, INC., a Texas corporation (“ Advanced Seismic ”, and together with Geokinetics, Processing, USA, Exploration, International Holdings, International, Management and Geokinetics Services, each a “ Borrower ” and collectively, the “ Borrowers ”), PNC BANK, NATIONAL ASSOCIATION (“ PNC ”), the various financial institutions named therein or which hereafter become a party thereto, (together with PNC, collectively, “ Lenders ”) and PNC, as agent for the Lenders (in such capacity, “ Agent ”).

WHEREAS, Borrowers, Agent and Lenders are parties to a Second Amended and Restated Revolving Credit and Security Agreement, dated as of May 25, 2007 (as amended, restated, supplemented or otherwise modified from time to time, the “ Loan Agreement ”), pursuant to which Agent and Lenders provide Borrowers with certain financial accommodations.

WHEREAS, Borrowers have requested that the Lenders amend the Loan Agreement as provided herein, subject to the terms and conditions set forth herein;

WHEREAS, subject to the satisfaction of the conditions set forth herein, Agent and the Lenders are willing to amend the Loan Agreement as provided herein;

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

1.   Definitions .   All capitalized terms not otherwise defined herein shall have the meanings given to them in the Loan Agreement.

2.   Amendments to Section 1.2 .   Effective as of the date hereof, the following definitions set forth in Section 1.2 of the Loan Agreement are hereby amended and restated in their entirety to read as follows:

“  ‘ Alternate Base Rate ’ shall mean, for any day, a rate per annum equal to the highest of (i) the Base Rate in effect on such day and (ii) the Federal Funds Open Rate in effect on such day plus 1/2 of 1% and (iii) the Daily LIBOR Rate plus one percent (1%).

For the purposes of this definition, “ Daily LIBOR Rate ” shall mean, for any day, the rate per annum determined by the Agent by dividing (x) the Published Rate by (y) a number equal to 1.00 minus the percentage prescribed by the Federal Reserve for determining the maximum reserve requirements with respect to any eurocurrency funding by banks on such day.  “ Published Rate ” shall mean the rate of interest published each Business Day in The Wall Street Journal “Money Rates” listing under the caption “London Interbank Offered Rates” for a one month period (or, if no such rate is published therein for any reason, then the Published Rate shall be the eurodollar rate for a one-month period as published in another publication determined by the Agent).”

“ ‘ Senior Debt Payments ” shall mean and include all cash actually expended by any Borrower to make (a) interest payments on any Advances hereunder, plus (b) payments for all fees, commissions and charges set forth herein and with respect to any Advances, plus (c) capitalized lease payments, plus (d) payments with respect to any other Indebtedness for borrowed money.”

“ ‘ Undrawn Availability Event ” shall mean such time as Undrawn Availability falls below $7,000,000 at any reporting date under this Agreement.”

3.   Amendment to Section 2.1 .   Effective as of the date hereof, Section 2.1(a)(iii) of the Loan Agreement is hereby amended and restated in its entirety to read as follows:

“(iii)   up to the amount equal to the lesser of:

(A)            80% of the Net Orderly Liquidation Value of Eligible Equipment that has been appraised pursuant to the most recent appraisal (whether initiated by Agent or requested by Borrowers pursuant to Section 9.19) acceptable to Agent (less any Eligible Equipment that has been sold), or

(B)           (I) $55,000,000 minus (II) the amount equal to $916,667 multiplied by the number of calendar months ended, beginning June 30, 2009, (the “Equipment Cap Reduction”) (the remainder of (I) minus (II), the “Equipment Advance Rate” and together with the Domestic Advance Rate and the Foreign Advance Rate, the “Advance Rates”), minus”

4.   Amendment to Section 7.5 .  Effective as of the date hereof, Section 7.5 of the Loan Agreement is hereby amended and restated in its entirety to read as follows:

“7.5. Loans.   Make advances, loans or extensions of credit to any Person, including any Parent, Subsidiary or Affiliate except with respect to (a) the extension of commercial trade credit in connection with the sale of Inventory or services in the Ordinary Course of Business (b) loans to its employees in the Ordinary Course of Business not to exceed the aggregate amount of $100,000 at any time outstanding, (c) loans to other Borrowers provided that (1) such loans shall be evidenced by a demand note (collectively, the “ Intercompany Notes ”), which Intercompany Notes shall be in form and substance reasonably satisfactory to Agent and shall be pledged and delivered to Agent pursuant to the applicable Pledge Agreement as additional collateral security for the Obligations; (2) Borrowers shall record all intercompany transactions on their Books and Records in a manner reasonably satisfactory to Agent; (3) the obligations of any Borrower under any such Intercompany Notes shall be subordinated to the Obligations of Borrowers hereunder in a manner reasonably satisfactory to Agent; (4) at the time any such intercompany loan or advance is made by a Borrower to any other Borrower and after giving effect thereto, such Borrowers shall be solvent and (5) no Default or Event of Default would occur and be continuing after giving effect to any such proposed intercompany loan and (d) loans to Foreign Subsidiaries provided that (1) such loans shall be evidenced by  Intercompany Notes, which Intercompany Notes shall be in form and substance reasonably satisfactory to Agent and shall be pledged and delivered to Agent pursuant to the applicable Pledge Agreement as additional collateral security for the Obligations; (2) Borrowers shall record all intercompany transactions on their Books and Records in a manner reasonably satisfactory to Agent; (3) the obligations of any Borrower under any such Intercompany Notes shall be subordinated to the Obligations of Borrowers hereunder in a manner reasonably satisfactory to Agent; (4) at the time any such intercompany loan or advance is made by a Borrower to any Foreign Subsidiary and after giving effect thereto, such Borrowers shall be solvent; (5) no Default or Event of Default would occur and be continuing after giving effect to any such proposed intercompany loan; and (6) no Undrawn Availability Event has occurred or would result from such proposed intercompany loan; provided , further , however , if an Undrawn Availability Event has occurred, Agent, in its sole discretion, may permit Borrowers to make loans to Foreign Subsidiaries pursuant to subclause (d) of this Section 7.5 provided that (x) after giving effect to any such loan, net advances to Foreign Subsidiaries are positive (i.e., the total amount of all advances made by Borrowers to Foreign Subsidiaries is less than the amount of funds paid or transferred by Foreign Subsidiaries to Borrowers) and (y) Agent has received from Borrowers a cash flow forecast in form and substance satisfactory to Agent in its sole discretion and Agent has notified Borrowers after reviewing such cash flow forecast that Borrowers may make such loans to Foreign