Schlumberger Technology Corp.

    This THIRD STANDSTILL AND AMENDMENT AGREEMENT (this "Third Standstill Agreement"), dated as of December 2, 2002, is among SEITEL, INC. (the "Company"), a Delaware corporation, each of its Subsidiaries identified below, and each of the investors listed on the signature pages hereto (together with successors and assigns of each, a "Noteholder," and collectively, the "Noteholders"). Capitalized terms have the respective meanings ascribed thereto in Section 1 hereof.

    WHEREAS, each of the 1995 Noteholders and the Company are party to those certain separate Note Purchase Agreements dated as of December 28, 1995 (collectively, as amended, the "1995 Note Purchase Agreement"), providing for the sale by the Company and the purchase by the 1995 Noteholders of the Company's 7.17% Series B Senior Notes due December 30, 2002 (the "Series B Notes") in the aggregate original principal amount of $27,500,000 and the Company's 7.48% Series C Senior Notes due December 30, 2002 (the "Series C Notes" and together with the Series B Notes, collectively, the "1995 Notes") in the aggregate original principal amount of $22,500,000; and

    WHEREAS, each of the 1999 Noteholders and the Company are party to those certain separate Note Purchase Agreements dated as of February 12, 1999 (collectively, as amended, the "1999 Note Purchase Agreement"), providing for the sale by the Company and the purchase by the 1999 Noteholders of the Company's 7.03% Series D Senior Notes due February 15, 2004 (the "Series D Notes") in the aggregate original principal amount of $20,000,000, the Company's 7.28% Series E Senior Notes due February 15, 2009 (the "Series E Notes") in the aggregate original principal amount of $75,000,000 and the Company's 7.43% Series F Senior Notes due February 15, 2009 (the "Series F Notes" and together with the Series D Notes and the Series E Notes, collectively, the "1999 Notes") in the aggregate original principal amount of $43,000,000; and

    WHEREAS, each of the 2001 Noteholders and the Company are party to those certain separate Note Purchase Agreements dated as of October 15, 2001 (collectively, the "2001 Note Purchase Agreement"), providing for the sale by the Company and the purchase by the 2001 Noteholders of the Company's 7.04% Series G Senior Notes due October 15, 2006 (the "Series G Notes") in the aggregate original principal amount of $20,000,000, the Company's 7.19% Series H Senior Notes due October 15, 2008 (the "Series H Notes") in the aggregate original principal amount of $50,000,000 and the Company's 7.34% Series I Senior Notes due October 15, 2011 (the "Series I Notes" and together with the Series G Notes and the Series H Notes, collectively, the "2001 Notes") in the aggregate original principal amount of $37,000,000; and

    WHEREAS, the 1995 Note Purchase Agreement, the 1999 Note Purchase Agreement and the 2001 Note Purchase Agreement are collectively referred to herein as the "Note Purchase Agreements;" and

    WHEREAS, the Series B Notes, the Series C Notes, the Series D Notes, the Series E Notes, the Series F Notes, the Series G Notes, the Series H Notes and the Series I Notes are collectively referred to herein as the "Notes;" and

    WHEREAS, the obligations of the Company under the Note Purchase Agreements and the Notes have been guaranteed by the Restricted Subsidiaries pursuant to the Subsidiary Guaranties; and

    WHEREAS, on the date hereof, the Company's records indicate that each Noteholder is the registered owner, in its own or its nominee's name, of one or more of the Notes; and

    WHEREAS, the Noteholders, the Company and the Subsidiary Guarantors are party to that certain Standstill and Amendment Agreement dated as of July 17, 2002 and that certain Second Standstill and Amendment Agreement dated as of October 15, 2002 (and together with various preceding standstill, forbearance and/or amendment letters and agreements between the Company and the Noteholders, collectively, the "Original Standstill Agreement") pursuant to which such Noteholders agreed to forbear until December 2, 2002 (the "Original Termination Date") from exercising rights and remedies they had pursuant to the Note Purchase Agreements as a result of the existence and occurrence of certain Events of Default and the Company agreed to comply with certain terms and conditions as more fully described therein; and

    WHEREAS, certain Defaults or Events of Default have occurred and continue to exist; and

    WHEREAS, the Company acknowledges and agrees that, upon the expiration of the Original Standstill Agreement, the Noteholders would have the right under the Note Purchase Agreements to accelerate the Notes immediately and otherwise exercise, or cause to be exercised, all rights and remedies available to the Noteholders under the Note Purchase Agreements and under law and in equity; and

    WHEREAS, the Company has requested that the Noteholders (a) continue to forbear from exercising any rights and remedies in respect of any Existing Event of Default or Potential Default during the Standstill Period, (b) extend the Original Termination Date and (c) provide certain other accommodations to the Company as set forth herein; and

    WHEREAS, the Company has, in consideration of the accommodations referred to in the immediately foregoing clause, agreed to comply with the terms and conditions of this Third Standstill Agreement; and

    WHEREAS, the Company and each Noteholder are desirous of entering into this Third Standstill Agreement on the terms and conditions hereinafter set forth.

    NOW, THEREFORE, in consideration of the matters referred to above, the mutual covenants set forth herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows: