Exhibit 10.1
 SECURED PROMISSORY NOTE
 $4,847,927.25
    
    Houston, Texas
    
    October 15, 2010Please note this amount
is not the total for 
sales order EQL1475.
It represents the amount
invoiced on
September 23, 2010
 MITCHAM INDUSTRIES, SERCEL, INC.,
      
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(A)
    
    Maker shall fail to pay, for a period longer than three (3) days after when
due, any installment of principal or interest hereunder or under any other instrument
or agreement between Maker and Payee;(B)
    
    Maker shall fail to perform any of the obligations, covenants or agreements
legally imposed by the terms of this Note or any instrument securing its payment or
any of the obligations, covenants or agreements legally imposed by the terms of any
other instrument or agreement between Maker and Payee, including the Security
Agreement (as defined below), which is not cured within ten (10) days after Maker
receives written notice from Payee;(C)
    
    Maker shall breach any representation and warranty made under this Note or
under the Security Agreement (as defined below) ;(D)
    
    Maker shall be merged with any entity when Maker is not the surviving company
or all or part of its assets or businesses are transferred to any third party.(E)
    
    Maker shall admit its inability to pay its debts as they mature or shall make
any assignment for the benefit of itself or any of its creditors;(E)
    
    Maker or any guarantor hereof shall default in the payment of any other
indebtedness Maker or any guarantor hereof owes to Payee or default in the performance
of any obligation set forth in any instrument securing the payment of any other
indebtedness Maker or such guarantor owes to Payee;(F)
    
    A receiver or trustee shall be appointed for the Maker or for any substantial
part of its assets, or any proceedings shall be instituted for the dissolution or the
full or partial liquidation of the Maker and, except with respect to any such
appointments requested or instituted by Maker, such receiver or trustee shall not be
discharged within thirty (30) days of his appointment, and, except with respect to any
such proceedings instituted by Maker, such
 
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proceedings shall not be discharged within thirty (30) days of their
commencement, or Maker shall discontinue business or materially change the nature
of its business; or(G)
    
    A creditor of Maker shall file or commence any levy of attachment, execution
or other similar process against assets of Maker valued in excess of $25,000 which
potential loss is not covered by insurance or which proceeding is not being contested
in good faith by Maker, or obtain possession of any of the Collateral (as defined in
the Security Agreement) by any means, including (without implied limitation) levy,
distraint, replevin, or self-help.
  ipso facto
 
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Makers Address:
    MAKER:MITCHAM INDUSTRIES,a corporation organized under the laws of Texas8175 Highway 75 South
    By:
    /s/ Robert P. CappsHuntsville TX 77340
    
    Name:
    Robert P. CappsUSA
    
    Title:
    Executive Vice President 
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Appendix A
 EQL1475
 Total Amount =
    
    
    4,847,927.25Number of Payments =
    
    
    18Down Payment
    
    
    1,210,672.25Interest Rate =
    
    
    8.00
    %Amount financed:
    
    
    3,637,255.00
 Due Date
    
    Payment
    
    Principal
    
    Interest
    
    Principal BalanceShip Date:
    
    10/8/20101
    
    November 15, 2010
    
    
    215,443.09
    
    
    
    185,149.24
    
    
    
    30,293.85
    
    
    
    3,452,105.762
    
    December 15, 2010
    
    
    215,443.09
    
    
    
    192,744.31
    
    
    
    22,698.78
    
    
    
    3,259,361.453
    
    January 15, 2011
    
    
    215,443.09
    
    
    
    193,297.29
    
    
    
    22,145.80
    
    
    
    3,066,064.154
    
    February 15, 2011
    
    
    215,443.09
    
    
    
    194,610.65
    
    
    
    20,832.44
    
    
    
    2,871,453.505
    
    March 15, 2011
    
    
    215,443.09
    
    
    
    197,821.02
    
    
    
    17,622.07
    
    
    
    2,673,632.486
    
    April 15, 2011
    
    
    215,443.09
    
    
    
    197,277.04
    
    
    
    18,166.05
    
    
    
    2,476,355.447
    
    May 15, 2011
    
    
    215,443.09
    
    
    
    199,160.20
    
    
    
    16,282.89
    
    
    
    2,277,195.238
    
    June 15, 2011
    
    
    215,443.09
    
    
    
    199,970.64
    
    
    
    15,472.45
    
    
    
    2,077,224.599
    
    July 15, 2011
    
    
    215,443.09
    
    
    
    201,784.63
    
    
    
    13,658.46
    
    
    
    1,875,439.9610
    
    August 15, 2011
    
    
    215,443.09
    
    
    
    202,700.37
    
    
    
    12,742.72
    
    
    
    1,672,739.5911
    
    September 15, 2011
    
    
    215,443.09
    
    
    
    204,077.63
    
    
    
    11,365.46
    
    
    
    1,468,661.9612
    
    October 15, 2011
    
    
    215,443.09
    
    
    
    205,786.13
    
    
    
    9,656.96
    
    
    
    1,262,875.8213
    
    November 15, 2011
    
    
    215,443.09
    
    
    
    206,862.45
    
    
    
    8,580.64
    
    
    
    1,056,013.3714
    
    December 15, 2011
    
    
    215,443.09
    
    
    
    208,499.44
    
    
    
    6,943.65
    
    
    
    847,513.9315
    
    January 15, 2012
    
    
    215,443.09
    
    
    
    209,684.64
    
    
    
    5,758.45
    
    
    
    637,829.2916
    
    February 15, 2012
    
    
    215,443.09
    
    
    
    211,109.35
    
    
    
    4,333.74
    
    
    
    426,719.9317
    
    March 15, 2012
    
    
    215,443.09
    
    
    
    212,730.79
    
    
    
    2,712.30
    
    
    
    213,989.1418
    
    April 15, 2012
    
    
    215,443.09
    
    
    
    213,989.14
    
    
    
    1,453.95
    
    
    
    0.003,877,975.66
    
    
    
    3,637,255.00
    
    
    
    240,720.66
 
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SECURITY AGREEMENT
 th MITCHAM INDUSTRIES, SERCEL, INC.,
 WITNESSETH:
 WHEREAS, Exhibit A
 WHEREAS,
 NOW, THEREFORE,
 Definitions.
 Security Interest, Collateral and Obligations .
 Grant and Obligations.
  Debtors Representations, Warranties and Agreements .
 
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Disposal of Collateral.
 Information.
 Other Liens.
 Covenants Concerning the Collateral .
 Insurance.
  
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Further Assurances.
 Power, Authority and Existence.
 Assessments.
 Time of the Essence.
 Event of Default.
 Rights of Secured Party .
 
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Rights After Default .
 Discharges, Liens, etc .
 U.C.C. Remedies .
 
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No Waiver .
 Assignment .
 Additional Agreements .
 Miscellaneous .
 Choice of Law .
  Illegality .
 Continuing Agreement .
 
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Amendments .
 Notice .
 DEBTOR :
 Address:
    MITCHAM INDUSTREIS8175 Highway 75 South
    By:
    /s/ Robert P. CappsHuntsville, TX 77340
    
    Name:
    Robert P. CappsTitle:
    Executive Vice President SECURED PARTY :
 Address:
    SERCEL, INC.17200 Park Row
    By:Houston, Texas 77084
    
    Name:Title: 
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MITCHAM INDUSTRIES
8175 Highway 75 South
Huntsville, TX 77340
USA
    
    (SERCEL LOGO)
 Exhibit A
 Please note this amount is not the total for sales order EQL1475. It represents the
amount invoiced on September 23, 2010.
 INVOCE No.
    
    INVOICE DATE
    
    INVOICE TOTAL50329
    
    June 30, 2010
    
    
    4,441,598.6851125
    
    August 31, 2010
    
    
    2,745.2751137
    
    August 31, 2010
    
    
    357,828.8051414
    
    September 23, 2010
    
    
    45,754.50TOTAL INVOICED AMOUNT:
    
    $
    4,847,927.25
 
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