Form Of Subordinated Promissory Note

GEOPHYSICAL, INC.


FORM OF SUBORDINATED PROMISSORY NOTE


US $250,000.00 October __, 1997
New York, New York


FOR VALUE RECEIVED, 3-D GEOPHYSICAL, INC., a Delaware corporation (the "Maker"), hereby promises to pay to the order of __________________ (the "Holder") the principal sum of ________________________________ DOLLARS ($__________.00), together with accrued and unpaid interest thereon, on April __, 1998 (the "Payment Date"), provided that if such Payment Date is not a Business Day, as defined below, payment shall be made on the next succeeding Business Day.


The payment of this Note is subordinated pursuant to the terms of a Subordination Agreement and Assignment, dated as of October __, 1997, by and among the Holder, the Maker and Wells Fargo Bank (Texas) N.A. (the "Subordination Agreement") and is subject to all of the terms and conditions of the Subordination Agreement.


1. Interest. Maker agrees to pay interest from the date hereof on the unpaid portion of the principal amount of this Note from time to time outstanding at the rate of 12% per annum through the Payment Date (but in no event higher than the maximum rate permitted by applicable law), compounded annually and payable on or before the Payment Date and thereafter until the principal amount of this Note is paid in full, subject to the provisions of Section 3 hereof.


2. Business Day. For the purposes of this Note, the phrase "Business Day" means any day that is not a Saturday or Sunday or a legal holiday on which banks are authorized or required by law to be closed in New York, New York.


3. Prepayment. Subject to its obligations under the Subordination Agreement, the Maker may, at its option, on five (5) Business Days notice to the Holder, prepay the principal amount of this Note at any time in whole, or from time to time in such ...