FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT AND DOMESTIC SECURITY AGREEMENT

Exhibit 10.1

FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT
AGREEMENT AND DOMESTIC SECURITY AGREEMENT

     This First Amendment to Amended and Restated Credit Agreement and Domestic Security Agreement (this “ Amendment ”) is made and entered into effective as of the 17 ^th day of September, 2008 (the “ First Amendment Effective Date ”), by and among ION GEOPHYSICAL CORPORATION, a Delaware corporation (the “ Domestic Borrower ”), ION INTERNATIONAL S.À R.L., a Luxembourg private limited company ( société à responsabilité limitée ), having its registered office at 560A rue de Neudorf, L-2220 Luxembourg, with a share capital of EUR12,500, and registered with the Luxembourg Register of Commerce and Companies under the number B-135.679 (the “ Foreign Borrower ” and together with the Domestic Borrower, the “ Borrowers ”), the Guarantors party hereto (the “ Guarantors ”), the Lenders party hereto, HSBC BANK USA, N.A. (“ HSBC ”), as Administrative Agent, Joint Lead Arranger and Joint Bookrunner, ABN AMRO INCORPORATED, as Joint Lead Arranger and Joint Bookrunner (“ ABN AMRO ”, in such capacity and together with HSBC, the “ Arrangers ”) and CITIBANK, N.A., as Syndication Agent.

RECITALS

     WHEREAS, the above-named parties have entered into that certain Amended and Restated Credit Agreement dated as of July 3, 2008 (as amended or restated from time to time prior to the date hereof, the “ Credit Agreement ”), by and among the Borrowers, the Guarantors, the Lenders and the Administrative Agent; and

     WHEREAS, the Borrowers have now asked the Lenders and the Administrative Agent to amend certain provisions of the Credit Agreement, including, without limitation, specifically to advance additional funds thereunder, amend certain covenants, make other changes and increase the Revolving Commitments thereunder, and said parties are willing to do so subject to the terms and conditions set forth herein, provided that the Domestic Borrower and Domestic Guarantors ratify and confirm all of their respective obligations under the Credit Agreement and each other Loan Document to which each is a party and that the Foreign Borrower and Foreign Guarantors ratify and confirm all of their respective obligations under the Credit Agreement and each other Loan Document to which each is a party.

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants set forth in this Amendment, Borrowers, Guarantors, the Lenders party hereto and the Administrative Agent agree as follows:

          1. Defined Terms . Unless otherwise defined herein, capitalized terms used herein have the meanings assigned to them in the Credit Agreement.

          2. Amendments . (a) The Credit Agreement is hereby amended as follows:

     (i) Amendments to Section 1.01 . Section 1.01 is hereby amended by deleting the following definitions and restating them in their entirety to read as follows:

“ Alternative Currency ” means with respect to any Loan or Letter of Credit, Euros, Pounds Sterling or Canadian Dollars.

“ Applicable Margin ” means, on any day, for any Revolving Loan, the applicable per annum percentage set forth at the appropriate intersection in the Revolving Loans table shown below, and, for the Term Loans, the applicable per annum percentage set forth at the appropriate intersection in the Term Loans table shown below, each of which is based on the Leverage Ratio for the most recently ended trailing four-quarter period with respect to which the Domestic Borrower is required to have delivered the financial statements and Compliance Certificate pursuant to Section 5.01 hereof (as such Leverage Ratio is reflected in the Compliance Certificate delivered under Section 5.01(c) by the Domestic Borrower in connection with such financial statements):

Revolving Loans

Term Loans

Each change in the Applicable Margin shall take effect on each date on which such financial statements and Compliance Certificate are required to be delivered pursuant to Section 5.01 , commencing with the date on which such financial statements and Compliance Certificate are required to be delivered for the four-quarter period ending June 30, 2008. Notwithstanding the foregoing, for the two (2) quarterly periods following the date of the initial Term Loan Borrowing, the Applicable Margin shall be determined at Level IV. In the event that any financial statement delivered pursuant to Section 5.01 is shown to be inaccurate when delivered (regardless of whether this Agreement or the Revolving Loan Commitments are in effect when such inaccuracy is discovered), and such inaccuracy, if corrected, would have led to the application of a higher Applicable Margin for any period (an “ Applicable Period ”) than the Applicable Margin applied for such Applicable Period, and only in such case, then the Domestic Borrower shall immediately (i) deliver to the Administrative Agent corrected financial statements for such Applicable Period, (ii) determine the Applicable Margin for such Applicable Period based upon the corrected financial statements, and (iii) immediately pay to the Administrative Agent the accrued

additional interest owing as a result of such increased Applicable Margin for such Applicable Period, which payment shall be promptly applied by the Administrative Agent in accordance with Section 2.16(a) . This provision is in addition to the rights of the Administrative Agent and the Lenders with respect to Section 2.11(d) and their other respective rights under this Agreement. If the Domestic Borrower fails to deliver the financial statements and corresponding Compliance Certificate to the Administrative Agent at the time required pursuant to Section 5.01 , then effective as of the date such financial statements and corresponding Compliance Certificate were required to the delivered pursuant to Section 5.01 , the Applicable Margin shall be determined at Level V and shall remain at such level until the date such financial statements and corresponding Compliance Certificate are so delivered by the Domestic Borrower. The Applicable Margin for the Term Loans shall be increased by 0.25% at all levels, and the Applicable Margin for the Revolving Loans shall be increased by 0.50% at all levels, in each case, commencing on the First Amendment Effective Date and ending on the date the Domestic Borrower repays the Revolving Loans borrowed for the purpose of financing the ARAM Acquisition.

“ Availability Period ” means (i) in regard to the Revolving Loans, the period from and including the Effective Date of the Credit Agreement to but excluding the earlier of the Revolving Credit Termination Date and the date of termination of all of the Revolving Loan Commitments as set forth herein and (ii) in regard to the Term Loan, the period from and including the First Amendment Effective Date to and including the sooner of (a) November 1, 2008, and (b) the date on which the Term Loans are funded.

“ Borrowing ” means Loans of the same Type, made, converted or continued on the same date and, in the case of any Loan to which the LIBO Rate is applicable, as to which a single Interest Period is in effect.

“ Borrowing Request ” means a request by either Borrower for a Revolving Loan Borrowing or a request by the Domestic Borrower for a Term Loan, in each case, in accordance with Section 2.03 .

“ Business Day ” means any day that is not a Saturday, Sunday or other day on which commercial banks in New York City, New York, Houston, Texas or Calgary, Alberta, Canada are authorized or required by Law to remain closed; provided that, when used in connection with a Eurodollar Loan or an Alternative Currency Loan, the term “Business Day” shall also exclude any day on which banks are not open for dealings in dollar deposits or Alternative Currencies in the London interbank market (and if the Borrowings which are the subject of a borrowing, drawing, payment, reimbursement or rate selection are denominated in Euros, the term “Business Day” shall also exclude any day that is not a TARGET day).

“ Compliance Certificate ” means the certificate required to be delivered pursuant to Section 5.01(b) .

“ Domestic Security Agreement ” means a Security and Pledge Agreement securing the Domestic Loans and guarantees thereof.

“ Excluded Taxes ” means, with respect to the Administrative Agent, any Lender, Issuing Lender or any other recipient of a payment to be made by or on account of any Obligation, (a) taxes imposed on or measured by its overall net income, however denominated, and

franchise taxes imposed on it (in lieu of net income taxes), by the jurisdiction (or any political subdivision thereof) under the laws of which such recipient is organized or in which its principal office is located or, in the case of any Lender, in which its applicable lending office is located; and (b) any branch profits taxes imposed by the United States of America or any similar tax imposed by any other jurisdiction in which a Lender is located.

“ Fee Letters ” means: (i) the letter agreement dated July 2, 2008, among the Borrowers and the Administrative Agent pertaining to certain fees payable to the Administrative Agent and (ii) the letter agreement dated August 28, 2008, between the Domestic Borrower and the Administrative Agent related to the Term Loan Commitments.

“ Interest Election Request ” means a request by either Borrower to convert or continue a Borrowing in accordance with Section 2.06 and substantially in the form attached hereto as Exhibit 2.06 or such other form reasonably acceptable to the Administrative Agent.

“ LC Exposure ” means, at any time, the sum of (a) the aggregate undrawn amount of all outstanding Letters of Credit at such time plus (b) the aggregate amount of all LC Disbursements that have not yet been reimbursed by or on behalf of a Borrower or converted into a Revolving Loan pursuant to Section 2.04(e) at such time. The LC Exposure of any Revolving Lender at any time shall be its Applicable Percentage of the total LC Exposure at such time.

“ Loans ” means all Revolving Loans and Term Loans made by the Lenders to a Borrower pursuant to this Agreement, and a Loan shall mean either a Revolving Loan or a Term Loan.

“ Material Contract ” means any contract or agreement, written or oral, to which a Borrower or any of its Subsidiaries is a party (other than the Loan Documents) that is listed as a “Material Contract” in the most recently filed Annual Report of the Domestic Borrower on Form 10-K, or in any Quarterly Report of the Domestic Borrower on Form 10-Q or Current Report of the Domestic Borrower on Form 8-K filed thereafter (each as may be amended) until the Form 10-K for the immediately succeeding fiscal year is filed.

“ Note ” has the meaning set forth in Section 2.08(h) .

“ Required Lenders ” means, at any time, Lenders having Revolving Credit Exposures, unused Revolving Loan Commitments and, prior to the funding of the Term Loans, and, as applicable, Term Loan Commitments, or, after the funding of the Term Loans, outstanding Term Loans, representing more than 50.0% of the sum of the total Revolving Credit Exposures, unused Revolving Loan Commitments and, as applicable, Term Loan Commitments or outstanding Term Loans at such time.

“ Restricted Payment ” means: (i) any dividend or other distribution (whether in cash, securities or other property) with respect to any Equity Interests in any Borrower or any of their Subsidiaries, or any payment (whether in cash, securities or other property), including any sinking fund or similar deposit, on account of the purchase, redemption, retirement, acquisition, cancellation or termination of any such Equity Interests in any Borrower, or any of their Subsidiaries or any option, warrant or other right to acquire any such Equity Interests in any Borrower or any of its Subsidiaries, or (ii) any principal repayment, defeasance, sinking fund or similar deposit, whether in cash, securities or other property, of the Junior Financing or the ARAM Sellers’ Note.

“ Revolving Credit Termination Date ” means July 3, 2013, provided , the Administrative Agent may accelerate the maturity date of the Revolving Loans such that the Revolving Credit Termination Date shall be the Advanced Maturity Date if the Junior Financing is not either paid in full or refinanced on or prior to the Advanced Maturity Date pursuant to terms reasonably satisfactory to the Administrative Agent, said acceleration to be effective upon written notice given to the Domestic Borrower by the Administrative Agent no later than thirty (30) days following the fourth anniversary date of the First Amendment Effective Date.

“ Revolving Loan ” means a Loan made pursuant to any of Sections 2.01(a)-(c) .

“ Super Majority Lenders ” means, at any time, Lenders having Revolving Credit Exposures, unused Revolving Loan Commitments and, prior to the funding of the Term Loans, and, as applicable, Term Loan Commitments, or, after the funding of the Term Loans, outstanding Term Loans, representing more than 66 2/3% of the sum of the total Revolving Credit Exposures, unused Revolving Loan Commitments and, as applicable, Term Loan Commitments or outstanding Term Loans at such time.

     (ii) Section 1.01 is hereby further amended by adding the following definitions thereto in the proper alphabetical order.

“ Advanced Maturity Date ” means the date that is six months prior to the date any Junior Financing (other than the Short Term Interim Junior Financing) is scheduled to mature.

“ ARAM ” means ARAM Systems Ltd., an Alberta corporation, and its permitted successors and assigns.

“ ARAM Acquisition ” means the acquisition of ARAM and certain of its subsidiaries or Affiliates, including Canadian Seismic Rentals, Inc., an Alberta corporation, pursuant to the terms of the ARAM Purchase Agreement.

“ ARAM Purchase Agreement ” means that certain Amended and Restated Share Purchase Agreement, dated as of September 17, 2008, by and among Domestic Borrower, ARAM, Canadian Seismic Rentals Inc. and the “Sellers” named therein, as amended, restated, or otherwise modified from time to time.

“ ARAM Sellers’ Note ” means that certain unsecured promissory note, in an aggregate principal amount not in excess of $35,000,000, that will mature no later than the first anniversary of the closing of the ARAM Acquisition, anticipated to be issued by 3226509 Nova Scotia Company, a Nova Scotia unlimited liability company and successor by assignment to the Domestic Borrower under the ARAM Purchase Agreement, made to the favor of the sellers of ARAM and certain of its Affiliates pursuant to the terms of the ARAM Purchase Agreement.

“ Canadian Dollars ” refers to lawful money of Canada.

“ Domestic Lenders ” means, collectively, the Domestic Revolving Lenders and the Term Loan Lenders.

“ Domestic Loans ” means collectively, the Domestic Revolving Loans and the Term Loans.

“ First Amendment ” means that certain First Amendment to Credit Agreement and Domestic Security Agreement, dated as of September 17, 2008, by and among the Domestic Borrower,

Foreign Borrower, the Guarantors party thereto, the Lenders party thereto, and the Administrative Agent.

“ First Amendment Effective Date ” means September 17, 2008.

“ Interim Junior Financing ” means one or more interim or bridge loans or financings, including, without limitation, the Short Term Interim Junior Financing, in a principal amount not exceeding $150,000,000 at any time outstanding, issued by any party to the Domestic Borrower as an intermediate financing vehicle to be refinanced or repaid from the proceeds of, or converted into, the Long Term Junior Financing on terms reasonably satisfactory to the Administrative Agent.

“ Junior Financing ” means the Interim Junior Financing or the Long Term Junior Financing, as applicable.

“ Long Term Junior Financing ” means (i) the unsecured notes or debentures in the original principal amount of up to $175,000,000, anticipated on the First Amendment Effective Date to be issued by the Domestic Borrower and underwritten by Jefferies & Company and/or Jefferies Finance or any Affiliate of either, or (ii) any extension of the Interim Junior Financing beyond the first anniversary thereof, which, in each case, shall have a stated maturity date of not less than five (5) years after the original date of issuance and shall be on terms reasonably satisfactory to the Administrative Agent.

“ Revolving Lender ” means a Lender making Revolving Loans hereunder.

“ Short Term Interim Junior Financing ” means one or more unsecured loans, with a maturity date of no later than December 31, 2008, and in an original principal amount not exceeding $41,000,000, made by any party to the Domestic Borrower as an intermediate financing vehicle to be repaid from the proceeds of any other Interim Junior Financing or the Long Term Junior Financing, on terms reasonably satisfactory to the Administrative Agent.

“ Term Loan ” means any Loans made pursuant to Section 2.01(e) hereof.

“ Term Loan Commitment ” means, with respect to each Term Loan Lender, the commitment of such Lender to make its Term Loan. The amount of each Term Loan Lender’s Term Loan Commitment is set forth on Schedule 2.01 , or in the Assignment and Assumption pursuant to which such Lender shall have assumed its Term Loan Commitment, as applicable. The initial aggregate amount of the Term Loan Lenders’ Term Loan Commitments is $125,000,000.

“ Term Loan Lender ” means a Lender making a portion of the Term Loans hereunder.

“ Term Loan Maturity Date ” means September 17, 2013, provided , the Administrative Agent may accelerate the maturity date of the Term Loans such that the Term Loan Maturity Date shall be the Advanced Maturity Date if the Junior Financing is not either paid in full or refinanced on or prior to the Advanced Maturity Date pursuant to terms reasonably satisfactory to the Administrative Agent, said acceleration to be effective upon written notice given to the Domestic Borrower by the Administrative Agent no later than thirty (30) days following the fourth anniversary date of the First Amendment Effective Date.

     (iii) Section 1.01 is hereby further amended by changing the reference in “Change in Law” from “ Section 2.14(b)” to “ Section 2.13(b) ”.

          (b) Amendment to Section 2.01 . Section 2.01 is hereby amended by deleting Section 2.01 in its entirety and restating Section 2.01 to read as follows:

     “SECTION 2.01 Commitments . (a) Subject to the terms and conditions set forth herein, each Revolving Lender agrees to make Revolving Loans to a Borrower from time to time during the Availability Period in an aggregate principal amount up to such Lender’s Revolving Loan Commitment. Within the foregoing limits and subject to the terms and conditions set forth herein, each Borrower may borrow, prepay and reborrow Revolving Loans.”

     “(b) Subject to Section 2.18 , Revolving Loans may, at the option of the Domestic Borrower, be requested in an aggregate amount of not more than $75,000,000 or an Equivalent Amount in an Alternative Currency calculated as of the date such Loans are requested (each a “ Domestic Revolving Loan ”), provided , for the period commencing on the First Amendment Effective Date and ending on the date of the funding of the Junior Financing (other than the Short Term Interim Junior Financing), but in no event later than December 31, 2008, an aggregate amount of up to $110,000,000 of the Revolving Loan Commitment may be requested and advanced in Dollars notwithstanding anything to the contrary in Section 2.18(h) , provided further , until the closing of the ARAM Acquisition (including the payment of the cash portion of the consideration therefor), said amount shall be $85,000,000 plus the maximum amount available to be drawn under any Letters of Credit outstanding on the First Amendment Effective Date.

     “(c) Subject to Section 2.18 , Revolving Loans may, at the option of the Foreign Borrower, be requested in an aggregate amount of not more than $60,000,000 or an Equivalent Amount in an Alternative Currency calculated as of the date such Loans are requested (each a “ Foreign Revolving Loan ”).”

     “(d) Notwithstanding the foregoing clauses (b) and (c), the aggregate principal amount of all Foreign Revolving Loans and all Domestic Revolving Loans, including the total LC Exposure at any time outstanding, shall not exceed the total of all of the Revolving Lenders’ Revolving Loan Commitments.”

     “(e) Subject to the terms and conditions set forth herein, each Term Loan Lender agrees to make a single Term Loan to the Domestic Borrower on any Business Day during the applicable Availability Period, in an aggregate principal amount of up to such Lender’s Term Loan Commitment. The Term Loans shall be advanced in a single advance made by each Term Loan Lender in Dollars and the Term Loan Commitments shall automatically expire following said advance, provided that the Domestic Borrower shall continue to be able to continue or convert Term Loan Borrowings from one Type to another at the end of any applicable Interest Period, assuming no Default has occurred and is continuing. Amounts borrowed as Term Loans and repaid or prepaid may not be reborrowed.”

          (c) Amendment to Section 2.02 . Section 2.02 is hereby amended by re-lettering paragraphs (b), (c) and (d) thereof as paragraphs (c), (d) and (e) respectively, and restating paragraph (a) in its entirety, and adding a new paragraph (b), each to read as follows:

     “(a) Each Revolving Loan and any continuations of any Interest Periods thereunder or conversions from one Type of Borrowing to another shall be made as part of a Borrowing consisting of Revolving Loans made by the Revolving Lenders ratably in accordance with their respective Revolving Loan Commitments. The failure of any Revolving Lender to make any Revolving Loan required to be made by it shall not relieve any other Revolving Lender of its obligations hereunder; provided that the Revolving Loan Commitments of the Revolving Lenders are several and no Revolving Lender shall be responsible for any other Revolving Lender’s failure to make Revolving Loans as required.”

     “(b) The Term Loans and any continuations of any Interest Periods thereunder or conversions from one Type of Borrowing to another shall be made ratably by the Term Loan Lenders in accordance with their respective Term Loan Commitments. The failure of any Term Loan Lender to make its Term Loan shall not relieve any other Term Loan Lender of its obligations hereunder, provided the Term Loan Commitments of the Term Loan Lenders are several and no Term Loan Lender shall be responsible for the obligations of any other Term Loan Lender.”

          (d) Amendment to Section 2.03 . Section 2.03 is hereby amended by deleting the word “Revolving” in the first line thereof.

          (e) Amendment to Section 2.04 . Section 2.04 is hereby amended by replacing each reference to “Lender”, “Lender’s”, “Lenders’” and “Lenders” therein that is not preceded by the word “Issuing” with a reference to “Revolving Lender”, “Revolving Lender’s”, “Revolving Lenders’” and “Revolving Lenders”, respectively.

          (f) Amendment to Section 2.07 . Section 2.07 is hereby amended by replacing each reference therein to “Lenders’” and “Lenders” with a reference to “Revolving Lenders’” and “Revolving Lenders”, respectively.

          (g) Amendment to Section 2.08 . Section 2.08 is hereby amended by relettering paragraphs (b) through (g) as paragraphs (c) through (h), respectively (and all references in the Credit Agreement to such paragraphs shall be relettered accordingly), by restating paragraph (a) in its entirety, restating paragraph (f) (formerly paragraph (e)) in its entirety, and by inserting a new paragraph (b), each to read as follows:

     “(a) Each Borrower hereby unconditionally promises to pay to the Administrative Agent for the account of each Revolving Lender the then unpaid principal amount of each Revolving Loan made to such Borrower on the Revolving Credit Termination Date. In addition, the Domestic Borrower promises to repay all amounts borrowed as Revolving Loans that are used to fund

the ARAM Acquisition from the proceeds received from any Junior Financing (other than from the Short Term Interim Junior Financing) promptly following the funding thereof, or if there is no such funding, upon the cancellation of the commitment to provide such Junior Financing, and, in any event, irrespective of any commitment for, or funding of, such Junior Financing, on or before December 31, 2008.

     “(b) The Domestic Borrower hereby unconditionally promises to pay to the Administrative Agent for the account of each Term Loan Lender the then aggregate unpaid principal amount of the Term Loans made to such Borrower on the Term Loan Maturity Date. In addition, the principal balance of the Term Loan shall be repaid in installments paid quarterly in amounts shown on the schedule below, said payments to be made on the last Business Day of each fiscal