<PAGE>

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
   
                                  FORM 10-QSB/A
    
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(Mark One)
(X)  QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES 
     EXCHANGE ACT OF 1934

                      FOR THE PERIOD ENDED APRIL 30, 1998

( )  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE EXCHANGE ACT OF 
     1934 
                       COMMISSION FILE NUMBER 001-13490
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                            MITCHAM INDUSTRIES, INC.
           (Name of small business issuer as specified in its charter)

                   TEXAS                                   76-0210849
     (State or other jurisdiction of                     (I.R.S. Employer
      Incorporation or organization)                    Identification No.)

                             44000 HIGHWAY 75 SOUTH
                             HUNTSVILLE, TEXAS 77340
                    (Address of principal executive offices)

                                 (409) 291-2277
                           (Issuer's telephone number)

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     Check whether the issuer (1) has filed all reports required to be filed 
by Section 13 or 15(d) of the Exchange Act during the past 12 months (or for 
such shorter period that the registrant was required to file such reports, 
and (2) has been subject to such filing requirements for the past 90 days. 
Yes  X  No
    ---    ---

     State the number of shares outstanding for each of the issuer's classes 
of common equity, as of the latest practicable date: 9,510,658 shares of 
Common Stock, $.01 par value, were outstanding as of June 10, 1998.

     Transitional Small Business Disclosure Format (check one): Yes     No  X 
                                                                    ---    ---


                                      1

<PAGE>

                           MITCHAM INDUSTRIES, INC.
                                    INDEX



                        PART I. FINANCIAL INFORMATION

<TABLE>
<S>       <C>                                                               <C>
Item 1.   Consolidated Financial Statements

               Consolidated Balance Sheets................................... 3
               Consolidated Statements of Income............................. 4
               Consolidated Statements of Cash Flow.......................... 5
               Notes to Consolidated Financial Statements.................... 6

Item 2.   Management's Discussion and Analysis or Plan of
               Operation..................................................... 7

                        PART II. OTHER INFORMATION

Item 1.   Legal Proceedings ...............................................  10

Item 6.   Exhibits and Reports on Form 8-K.................................  11

          Signatures......................................................   11

</TABLE>


                                      2

<PAGE>

PART I.   FINANCIAL INFORMATION
ITEM 1.   FINANCIAL STATEMENTS

                            MITCHAM INDUSTRIES, INC.
                          CONSOLIDATED BALANCE SHEETS
                                 (In thousands)
<TABLE>
<CAPTION>
                                                                        April 30,     January 31,
                                     ASSETS                                1998           1998
                                                                       (Unaudited)     (Audited)
                                                                       -----------    -----------
<S>                                                                    <C>            <C>
CURRENT ASSETS:
  Cash                                                                   $1,704         $7,498
  Marketable securities, at market                                       19,855         25,009
  Accounts receivable, net                                               19,169         14,070
  Installment trade receivables                                             331            444
  Inventory                                                               1,074            942
  Prepaid expenses and other current assets                                 196            248
  Income tax receivable                                                     227            211
  Deferred income taxes                                                     321              -
                                                                        -------       --------
    Total current assets                                                 42,877         48,422
  Seismic equipment lease pool, net                                      37,749         42,236
  Property and equipment, net                                               870            898
  Other assets                                                                -              6
                                                                        -------        -------
    Total assets                                                        $81,496        $91,562
                                                                        -------        -------
                                                                        -------        -------

                        LIABILITIES AND STOCKHOLDERS' EQUITY
CURRENT LIABILITIES:
  Accounts payable                                                        1,364          8,400
  Deferred income taxes payable                                               -             45
  Deferred revenue                                                        1,321          1,055
  Income taxes payable                                                        -              -
  Accrued liabilities and other current liabilities                         251          5,532
                                                                        -------        -------
    Total current liabilities                                             2,936         15,032
DEFERRED INCOME TAXES                                                     2,700          2,294
                                                                        -------        -------
    Total liabilities                                                     5,636         17,326

STOCKHOLDERS' EQUITY:
  Preferred stock, $1.00 par value; 1,000,000 shares authorized;
    none issued and outstanding                                               -              -
  Common stock, $.01 par value; 20,000,000 shares authorized
    9,454,824 and 9,425,759 shares, respectively, issued and
    outstanding                                                              95             94
  Additional paid-in capital                                             61,314         61,275
  Retained earnings                                                      14,451         12,770
    Cumulative translation adjustment                                         -             97
                                                                        -------        -------
    Total stockholders' equity                                           75,860         74,236

    Total liabilities and stockholders' equity                          $81,496        $91,562
                                                                        -------        -------
                                                                        -------        -------
</TABLE>

                            See accompanying notes


                                      3

<PAGE>

                             MITCHAM INDUSTRIES, INC.
                        CONSOLIDATED STATEMENTS OF INCOME
                       (in thousands except per share data)

<TABLE>
<CAPTION>
                                                                             Three Months
                                                                            ended April 30,
                                                                       --------------------------
                                                                           1998           1997
                                                                       -----------    -----------
<S>                                                                    <C>            <C>
REVENUES:
  Short-term leasing                                                       $5,890        $4,043
  Lease/purchase activities:
    Leasing revenues                                                        1,200           363
    Sales of equipment                                                      7,336           765
  Sales of seismic equipment                                                1,026           365
  Sales commissions                                                             1             -
                                                                       ----------    ----------
    Total revenues                                                         15,453         5,536
                                                                       ----------    ----------
COSTS AND EXPENSES:
  Seismic equipment subleases                                               271              42
  Cost of Sales:
    Sales of seismic equipment under lease/purchase
      Agreements                                                            7,343           598
      Other sales of seismic equipment                                        570           339
  Repairs, net                                                                155             -
  General and administrative                                                1,309           586
  Provision for doubtful accounts                                             608           289
  Depreciation                                                              2,712         1,219
                                                                       ----------    ----------
    Total costs and expenses                                               12,968         3,073
                                                                       ----------    ----------
OPERATING INCOME                                                            2,485         2,463
OTHER INCOME (EXPENSE):
  Interest, net                                                                63           155
  Other, net                                                                   38             2
                                                                       ----------    ----------
    Total other income (expenses)                                             101           157
                                                                       ----------    ----------
INCOME BEFORE INCOME TAXES                                                  2,586         2,620
PROVISION FOR INCOME TAXES                                                    906           897
                                                                       ----------    ----------
NET INCOME                                                             $    1,680    $    1,723
                                                                       ----------    ----------
                                                                       ----------    ----------
Earnings per common and share
  Basic                                                                $      .18    $      .28
  Diluted                                                              $      .17    $      .28
                                                                       ----------    ----------
                                                                       ----------    ----------
Shares used in computing earnings per common share
  Basic                                                                 9,437,000     6,060,000
  Diluted                                                               9,757,000     6,239,000
                                                                       ----------    ----------
                                                                       ----------    ----------
</TABLE>

                             See accompanying notes.


                                      4

<PAGE>

                          MITCHAM INDUSTRIES, INC.
                   CONSOLIDATED STATEMENTS OF CASH FLOWS
                               (In thousands)

<TABLE>
<CAPTION>
                                                                             Three Months
                                                                            ended April 30,
                                                                       --------------------------
                                                                           1998           1997
                                                                       -----------    -----------
<S>                                                                    <C>            <C>
CASH FLOWS FROM OPERATING ACTIVITIES:

Net income                                                              $1,680         $1,723
Adjustments to reconcile net income to net
  cash flows provided by operating activities:
    Depreciation                                                         2,712            961
    Provision for doubtful accounts, net of charge offs                    441            200
    Deferred income taxes                                                  361            268
    Trade accounts receivable                                           (5,427)        (2,043)
    Accounts payable and other current liabilities                      (7,888)        (1,170)
    Other, net                                                            (360)            51
                                                                       --------       --------
      Net cash provided by (used in) operating activities               (8,529)           (10)

CASH FLOWS FROM INVESTING ACTIVITIES:
  Purchases of seismic equipment held for lease                         (4,415)        (1,693)
  Purchases of property and equipment                                      (88)          (161)
  Disposal of lease pool equipment                                       7,043            778
                                                                       --------       --------
         Net cash used in investing activities                           2,540         (1,076)

CASH FLOWS FROM FINANCING ACTIVITIES:
  Payment on short-term borrowings                                          -          (1,937)
  Payments on long-term debt and capitalized lease obligations              -          (2,626)
  Proceeds from issuance of common stock, net of offering expenses          -          18,108
  Proceeds from issuance of common stock upon exercise of
    Warrants and options                                                    40              -
  Proceeds from sale of marketable securities                              155              -
                                                                       --------       --------
    Net cash provided by financing activities                              195         13,545
                                                                       --------       --------

NET INCREASE IN CASH                                                    (5,794)        12,459
CASH, BEGINNING OF PERIOD                                                7,498            301
                                                                       --------       --------
CASH, END OF PERIOD                                                    $ 1,704        $12,760
                                                                       --------       --------
                                                                       --------       --------

SUPPLEMENTAL CASH FLOW INFORMATION
   Cash paid for:
     Interest                                                          $     -        $    17
     Taxes                                                             $   801              -
                                                                       --------       --------
                                                                       --------       --------
     Equipment purchases in accounts payable                           $   757        $   429
                                                                       --------       --------
                                                                       --------       --------
</TABLE>

                             See accompanying notes.


                                      5

<PAGE>
                            MITCHAM INDUSTRIES, INC.
                    NOTES TO CONSOLIDATED FINANCIAL STATEMENTS



        1.   The consolidated financial statements of Mitcham Industries, Inc.
             ("the Company") have been prepared by the Company, without audit,
             pursuant to the rules and regulations of the Securities and
             Exchange Commission. Certain information and footnote disclosures
             normally included in financial statements prepared in accordance
             with the generally accepted accounting principles have been
             condensed or omitted pursuant to such rules and regulations,
             although the Company believes that the disclosures are adequate to
             make the information presented not misleading. These condensed
             financial statements should be read in conjunction with the
             financial statements and the notes thereto included in the
             Company's latest Annual Report to Shareholders and the Annual
             Report on Form 10-KSB for the year ended January 31, 1998. In the
             opinion of the Company, all adjustments, consisting only of normal
             recurring adjustments, necessary to present fairly the financial
             position as of April 30, 1998, and the results of operations and
             cash flows for the three months ended April 30, 1998 and 1997 have
             been included.

        2.   On April 23, 1998, a class action lawsuit was filed against the
             Company and its chief executive officer and chief financial officer
             in the U.S. District Court for the Southern District of Texas,
             Houston Division. The complaint, styled STANLEY MOSKOWITZ V.
             MITCHAM INDUSTRIES, INC., BILLY F. MITCHAM, JR. AND ROBERTO RIOS,
             alleges violations of Section 10(b) and 20(a) of the Securities
             Exchange Act of 1934 and Sections 11 and 12(a)(2) of the Securities
             Act of 1933. The complaint seeks class action status on behalf of
             those who purchased the Company's common stock from June 4, 1997
             through March 26, 1998 and damages in an unspecified amount plus
             costs and attorney's fees. The complaint alleges materially false
             and misleading misrepresentations and omissions in public filings
             and announcements concerning the Company's business and its
             allowance for doubtful accounts. The Company believes that the
             plaintiffs' allegations are without merit and that there are
             meritorious defenses to the allegations, and intends to defend the
             action vigorously.

        3.   Effective May 29, 1998, the Company, agreed in principle to the 
             terms of a new Preferred Supplier Agreement with Input/Output, 
             Inc. ("I/O"). The definitive agreement is expected to be signed no
             later than June 30, 1998, and will replace the parties' Exclusive
             Lease Referral Agreement.

             The terms provide that the Company will purchase a minimum of
             between $90 and $100 million of I/O products over a five year term.
             In addition I/O will refer rental inquiries from customers
             worldwide to the Company during the term of the agreement.

             In a related transaction, I/O sold to the Company, for $15 million
             a substantial portion of its subsidiary's equipment lease pool, 
             some of which is subject to existing short-term lease agreements. 
             The Company has until June 30, 1998 to purchase the remaining 
             portion of I/O's subsidiary's equipment lease pool, including the 
             assignment of existing short-term lease agreements. I/O has agreed
             in principle not to lease products covered by the Preferred 
             Supplier Agreement except in limited circumstances.

        4.   The foregoing interim results are not necessarily indicative of the
             results of the operations for the full fiscal year ending January
             31, 1999.


                                       6
<PAGE>

FORWARD-LOOKING STATEMENTS

     Certain information contained in this Quarterly Report on Form 10-QSB
(including statements contained in Part I, Item 2. "Management's Discussion and
Analysis or Plan of Operation" and in Part II, Item 1. "Legal Proceedings"), as
well as other written and oral statements made or incorporated by reference from
time to time by the Company and its representatives in other reports, filings
with the Securities and Exchange Commission, press releases, conferences, or
otherwise, may be deemed to be forward-looking statements within the meaning of
Section 21E of the Securities Exchange Act of 1934. This information includes,
without limitation, statements concerning the Company's future financial
position and results of operations; planned capital expenditures; business
strategy and other plans for future operations; the future mix of revenues and
business; contingent liabilities; Year 2000 issues; and future demand and
industry conditions. Although the Company believes that the expectations
reflected in such forward-looking statements are reasonable, it can give no
assurance that such expectations will prove to have been correct. When used in
this report, the words "anticipate," "believe," "estimate," "expect," "may," and
similar expressions, as they relate to the Company and its management, identify
forward-looking statements. The actual results of future events described in
such forward-looking statements could differ materially from those results which
might be anticipated, forecast or estimated by the Company in such
forward-looking statements due to risks and uncertainties such as volatility of
the oil and gas industry and demand for services; dependence upon additional
lease contracts; customer concentration and credit losses; industry consolation;
the risk of technical obsolescence of the Company's seismic lease fleet;
vulnerability to weather conditions and seasonality of results; dependence upon
key suppliers, and other factors (as further described in the Company's Annual
Report on Form 10-KSB) and other risks and uncertainties set forth from time to
time in the Company's other public reports and public statements.

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OR PLAN OF OPERATION

OVERVIEW

     The Company leases and sells seismic equipment primarily to seismic data
acquisition companies and oil and gas companies conducting land and transition
zone seismic surveys worldwide. The Company provides short-term leasing of
seismic equipment to meet a customer's requirements and offers maintenance and
support during the lease term. All leases at April 30, 1998 were for a term of
one year or less. Seismic equipment held for lease is carried at cost, net of
accumulated depreciation.

     For the years ended January 31, 1997 and 1998, revenues from foreign
customers totaled $6.8 million and $17.1 million, respectively. While most of
the Company's transactions with foreign customers are denominated in United
States dollars, some of the Company's transactions with Canadian customers are
denominated in Canadian dollars. The Company has not been subject to material
gains or losses resulting from currency fluctuations and has not engaged in
currency hedging activities.

SEASONALITY

     Historically, seismic equipment leasing has been susceptible to weather
patterns in certain geographic regions. There is some seasonality to the
Company's lease revenues from customers operating in Canada, where a significant
percentage of the seismic survey activity occurs in the winter months, from
October through March. During the months in which the weather is warmer, certain
areas are not accessible to trucks, earth vibrators and other heavy equipment
because of the unstable terrain. This seasonal leasing


                                       7
<PAGE>

activity by the Company's Canadian customers has historically resulted in
increased lease revenues in the Company's first and fourth fiscal quarters.

RESULTS OF OPERATIONS

FOR THE THREE MONTH PERIOD ENDED APRIL 30, 1998 AND 1997

     Revenues for the three month period ended April 30, 1998 of $15.5 million
represented an increase of $9.9 million, or 179%, over the same prior year
period revenues of $5.5 million. Short-term leasing services generated revenues
of $5.9 million for the three month period ended April 30, 1998, an increase of
$1.8 million, or 46%, as compared to $4.0 million for the same prior year
period. This increase reflected additions to the equipment lease pool to meet
lease demand. Seismic equipment sales for the three month period ended April 30,
1998 were $1.0 million, an increase of $661,000 or 181%, as compared to $365,000
for the same prior year period. The increase in sales was due primarily to
customer purchases of lease pool equipment at the end of the lease contract that
were not entered into originally as a lease/purchase contract. The Company's
customers in several instances preferred to enter into a lease of seismic
equipment with an option to purchase at the end of the lease term. Lease
services from lease/purchase contracts generated revenues of $1.2 million for
the three month period ended April 30, 1998, an increase of $837,000 or 231%, as
compared to $363,000 for the same prior year period, and sales from
lease/purchase equipment generated revenues of $7.3 million, an increase of $6.6
million or 859%, as compared to $765,000 for the same prior year period. The
increase in lease/purchase revenues was due primarily to an increase in
customer's demand for lease/purchase option contracts.

     The Company's leasing revenues from both short-term leasing services and
lease/purchase contracts increased by $2.7 million. The Company's sublease costs
increased by $229,000, or 545%, and depreciation, which related primarily to
equipment available for lease, increased by $1.5 million, or 122%, due to the
increase in the equipment lease pool, resulting in an increase in net short-term
leasing revenues of $962,000.

     There were no margins on sales of equipment under lease/purchase agreements
for the three month period ended April 30, 1998 and 22% for the prior year
period. Gross margins decreased significantly due primarily to one transaction
involving leased equipment that had only recently been purchased and added to
the Company's equipment lease pool.

     Gross margins on seismic equipment sales were 44% and 7% for the three 
month period ended April 30, 1998 and 1997, respectively. Gross margins 
increased in the fiscal 1998 period because the Company had a few high margin 
transactions during the quarter.

     General and administrative expenses increased $723,000, or 123%, for the
three month period ended April 30, 1998 as compared to the same prior year
period and were 8% and 11% of total revenues, respectively. Although general and
administrative expenses increased due in part to increased personnel costs and
costs associated with the office in Canada, general and administrative expenses
decreased as a percentage of total revenues.

     The Company's provision for doubtful accounts expense increased from
$289,000 in the same prior year period to $608,000 for the three month period
ended April 30, 1998. The increase was a result of increased business which
resulted in an increase in net accounts receivable of 36%. The provision for


                                       8
<PAGE>

doubtful accounts expense was 4% of total revenues in for the three month period
ended April 30, 1998 and 5% of total revenues in the same prior year period. As
of April 30, 1998, the Company's allowance for doubtful accounts was
approximately $1.5 million.

     Net income for the three month period ended April 30, 1998 was $1.7 
million, which  decreased  slightly by $43,000, as compared to the same prior 
year period.

LIQUIDITY AND CAPITAL RESOURCES

     As of April 30, 1998, the Company had net working capital of approximately
$39.9 million and $15.0 million of availability under its bank credit
facilities. Net cash provided by operating activities for the three month period
ended April 30, 1998 decreased by $8.5 million, as compared to the same prior
year period, primarily as a result of an increase in trade accounts receivable
and a decrease in accounts payable. At April 30, 1998, the Company had trade
accounts receivable of $5.7 million that were more than 90 days past due, with
four customers owing an aggregate of $3.4 million of such amount. As of April
30, 1998, the Company's allowance for doubtful accounts was approximately $1.5
million, which management believes is sufficient to cover any losses in its
trade accounts receivable, including any losses in its international customers'
trade accounts.

     Although the Company has not received payment on the pre-bankruptcy 
petition claims from Grant Geophysical, the Company expects to collect 
one-half of pre-bankruptcy petition claims, which total approximately 
$755,000. The Company's Chief Financial Officer serves on the creditors' 
committee. The Company is currently leasing seismic equipment to Grant.

     Prior to December 8, 1997, the Company had a $5.0 million line of credit
with Bank One, Texas, N.A. ("Bank One"). As of December 8, 1997, the Company
replaced the previous line of credit with a working capital revolving line of
credit of up to $15 million from Bank One (the "New Revolver"). Interest on
advances under the New Revolver are payable monthly at a variable rate which is
based upon either, at the Company's option, LIBOR or Bank One's base lending
rate. The LIBOR rate, if elected, will range between LIBOR plus 1.75% and LIBOR
plus 2.75% depending upon the debt service coverage ratio the Company maintains.
Similarly, the Bank One base lending rate, if elected, will range between the
base rate minus 0.25% and the base rate plus 0.25%, again depending upon the
Company's debt service coverage ratio. Additionally, the Company will owe Bank
One each fiscal quarter a fee equal of 0.25% of the average daily unused portion
of the New Revolver calculated for the previous quarter. Advances will be
limited to the total of 80% of eligible accounts receivable and 50% of all
eligible lease pool equipment. The New Revolver contains restrictions, among
others, on the ability of the Company to incur indebtedness and pay dividends
and requires the Company to meet certain financial covenants, including a
minimum tangible net worth, a debt service coverage ratio, aging of accounts
receivable and net income. The New Revolver will expire on December 8, 1999, at
which time the unpaid principal amount of the New Revolver will be due and
payable in full. As of April 30, 1998, the Company had not drawn any amounts
under the New Revolver.

     Capital expenditures in the first quarter of fiscal 1999 totaled $5.2
million. As of April 30, 1998, the Company had satisfied all minimum purchase
requirements of equipment under both its Exclusive Lease Referral Agreement with
Input/Output, Inc. ("I/O") and its Exclusive Equipment Lease Agreement with
Sercel. Effective May 29, 1998, the Company entered into an Equipment Purchase
Agreement with I/O, pursuant to which the Company purchased a substantial 
portion of the equipment lease pool of I/O's wholly-owned subsidiary for 
$15 million, some of which equipment is subject to existing short-term lease
agreements. The Company has until June 30, 1998, to 


                                       9
<PAGE>

purchase the remaining portion of I/O's subsidiary's equipment lease pool, 
including the assignment of existing short-term lease agreements, at a price 
to be agreed upon.

     In a related transaction, the Company and I/O agreed in principle to terms
of a new Preferred Supplier Agreement. The definitive agreement is expected to
be signed by June 30, 1998, and will replace the parties' Exclusive Lease
Referral Agreement. The terms provide that the Company will purchase a minimum
of between $90 to $100 million of I/O equipment (after applicable discounts and
credits) over a five-year term. In addition, I/O will refer to the Company
equipment lease inquiries from its customers worldwide during the term of the
Agreement. The new agreement covers all equipment and products currently
manufactured and sold by I/O, and, in consideration for the Company's minimum
purchase commitments, I/O has agreed that it will not offer more favorable
pricing for any other company in the seismic equipment leasing business.
Likewise, the Company has agreed that it will not offer for resale to third
parties I/O equipment manufactured less than three years from the date of offer,
unless such equipment is offered pursuant to the Company's lease/purchase
agreements.

     In the first year of the Preferred Supplier Agreement, the Company is
required to purchase a minimum of $30 million of equipment (which includes the
$15 million purchase of I/O's subsidiary's lease pool equipment), before
applicable discounts and credits. The Company has budgeted capital expenditures
of approximately $40 million for fiscal 1999, which includes the above
minimum purchase requirements. Management believes that the net proceeds of the
December 1997 offering, ($11.4 million remaining) cash provided by operations
and funds available from its commercial lender will be sufficient to fund its
operations and budgeted capital expenditures for fiscal 1999.

     YEAR 2000. The Company has begun to address possible remedial efforts in
connection with computer software that could be affected by the Year 2000
problem. The Year 2000 problem is the result of computer programs being written
using two digits rather than four to define the applicable year. Any programs
that have time-sensitive software may recognize a date using "00" as the year
1900 rather than the year 2000. This could result in a major system failure or
miscalculations. The Company has been informed by the suppliers of substantially
all of the Company's software that all of those suppliers' software that is used
by the Company is Year 2000 compliant. The software from these suppliers is used
in major areas of the Company's operations such as for financial, sales,
warehousing and administrative purposes. The Company has no internally generated
software. After reasonable investigation, the Company has not yet identified any
Year 2000 problem but will continue to monitor the issue. However, there can be
no assurances that Year 2000 problem will not occur with respect to the
Company's computer systems. The Year 2000 problem may impact other entities with
which the Company transacts business, and the Company cannot predict the effect
of the Year 2000 problem on such entities.


                           PART II. OTHER INFORMATION


ITEM 1.  LEGAL PROCEEDINGS

         On April 23, 1998, a class action lawsuit was filed against the Company
and its chief executive officer and chief financial officer in the U.S. District
Court for the Southern District of Texas, Houston Division. The complaint,
styled STANLEY MOSKOWITZ V. MITCHAM INDUSTRIES, INC., BILLY F. MITCHAM, JR. AND
ROBERTO RIOS, alleges violations of Section 10(b) and 20(a) of the Securities
Exchange Act of 1934 and Sections 11 and 12(a)(2) of the Securities Act of 1933.
The complaint seeks class action status on behalf of those who purchased the
Company's common stock from June 4, 1997 through March 26, 1998 and 


                                       10
<PAGE>

damages in an unspecified amount plus costs and attorney's fees. The 
complaint alleges materially false and misleading misrepresentations and 
omissions in public filings and announcements concerning the Company's 
business and its allowance for doubtful accounts. The Company believes that 
the plaintiffs' allegations are without merit and that there are meritorious 
defenses to the allegations, and intends to defend the action vigorously.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

   (A)   REPORTS ON 8K
         No reports on Form 8K were filed by the Company during the quarter
         ended April 30, 1998.

   (B)   EXHIBITS
         10.1 - Equipment Purchase Agreement, effective May 29, 1998, between
         the Company, Input/Output, Inc., and I/O's subsidiary.

         11 - Statement of Computation of Earnings Per Share

         27 - Financial Data Schedule

   
    
                                   SIGNATURES


In accordance with the requirements of the Securities Exchange Act of 1934, the
registrant has caused this report to be signed on its behalf by the undersigned,
thereunto duly authorized.

   
     Date:  June 22, 1998



                           MITCHAM INDUSTRIES, INC.


                           /s/ ROBERTO RIOS
                           ------------------------------------
                           ROBERTO RIOS,
                           VICE PRESIDENT FINANCE, SECRETARY AND TREASURER
                           (AUTHORIZED OFFICER AND PRINCIPAL ACCOUNTING OFFICER)
    

                                       11