Exhibit
10.2
 SECURITY AGREEMENT
 THIS SECURITY AGREEMENT Security Agreement th DAWSON GEOPHYSICAL COMPANY, Debtor WESTERN
NATIONAL BANK Secured Party
 NOTICE IS TAKEN OF THE FOLLOWING:
 A.
    
    Reference is made to that certain Loan Agreement, dated as of June 30, 2011, by and between
DAWSON GEOPHYSICAL COMPANY, as Borrower ( the Borrower), and the Secured Party, as Lender (the
Loan Agreement). Pursuant to the terms of the Loan Agreement, the Secured Party has agreed to
advance two loans to Borrower, from time to time, with those loans to be evidenced by: (i) that
certain Revolving Line of Credit Note, dated as of June 2, 2011, in the original principal amount
of Twenty Million and No/100 Dollars ($20,000,000.00), executed by the Borrower, as Maker, to the
Secured Party, as Payee (the Revolver Note), and (ii) that certain Term Note, dated as of June
30, 2011, in the original principal amount of Sixteen Million Four Hundred Twenty-Six Thousand Six
Hundred Eighty and Six/100 Dollars ($16,426,680.06), executed by the Borrower, as Maker, to the
Secured Party, as Payee (the Term Note). The Revolver Note and the Term Note are collectively
referred to herein as the Notes. The Loan Agreement, the Notes, and all documents executed by the
parties simultaneously therewith, as any of the same may be amended, extended or replaced from time
to time are collectively referred to herein as the Credit Documents. Capitalized terms not
otherwise defined herein are used with the same meanings as in the Credit Documents.B.
    
    To induce Secured Party to extend such credit, and in support of its performance under the Loan
Agreement and the Notes, Debtor has agreed to pledge and to grant to Secured Party a security
interest in and lien upon certain property of Debtor described more particularly herein.
 NOW, THEREFORE,
 AGREEMENT
 1.
    
    Grant of Security InterestDebtor hereby pledges and grants to Secured Party a security interest in the property described in
paragraph 2 (collectively and severally, the Collateral) to secure payment and performance of the
obligations described in paragraph 3 (collectively and severally, the Obligations).
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2.
    
    CollateralThe Collateral shall consist of all of the Debtors interest in the following:
 (i)
    
    All of Debtors Accounts and Equipment, as those terms are defined under the Uniform Commercial
Code, as adopted by the State of Texas, in effect as of the date of this Agreement; (ii) any
related or additional property from time to time delivered to or deposited with Secured Party by or
for the account of Debtor expressly securing the Obligations; (iii) all proceeds, products,
replacements, additions to, substitutions for, accessions of, and property necessary for the
operation of any of the foregoing, including, without limitation, insurance payable as a result of
loss or damage to the foregoing property and any proceeds thereunder, refunds or unearned premiums
of any such insurance policy, and claims against third parties; (iv) all books and records related
to any of the foregoing, including without limitation any and all books of account, customer lists
and other records relating in any way to the accounts receivable; and (v) any of the aforementioned
collateral hereafter acquired by Debtor as well as Collateral which Debtor now owns or in which
Debtor otherwise has rights related to any property referred to in this Section 2.
 3.
    
    ObligationsThe Obligations secured by this Security Agreement shall consist of any and all debts, obligations,
and liabilities of Debtor to Secured Party arising out of or related to the Credit Documents
(whether principal, interest, fees, or otherwise, whether now existing or thereafter arising,
whether voluntary or involuntary, whether or not jointly owed with others, whether direct or
indirect, absolute or contingent, contractual or tortious, liquidated or unliquidated, arising by
operation of law, or otherwise, whether or not from time to time decreased or extinguished and
later increased, created or incurred, and whether or not extended, modified, rearranged,
restructured, refinanced, or replaced, including without limitation, modifications to interest
rates or other payment terms of such debts, obligations, or liabilities).4.
    
    Representations and WarrantiesIn addition to any representations and warranties of Debtor set forth in the Credit Documents,
which are incorporated herein by this reference, Debtor hereby represents and warrants that:
 a.
    
    Authority.It has authority, and has completed all proceedings and obtained all approvals and
consents necessary, to execute, deliver, and perform this Security Agreement and the transactions
contemplated hereby.
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b.
    
    No Default or Lien.Such execution, delivery, and performance will not contravene, or constitute
a default under or result in a lien upon any property of Debtor pursuant to any applicable law or
regulation or any contract, agreement, judgment, order, decree, or other instrument binding upon or
affecting Debtor.c.
    
    Enforceability.This Security Agreement constitutes a legal, valid, and binding obligation of
Debtor, enforceable in accordance with its terms (except as enforceability may be affected by
bankruptcy, insolvency, or other similar laws affecting the enforcement of creditors rights), and
this Security Agreement grants to Secured Party a valid, first-priority perfected and enforceable
lien on the Collateral.d.
    
    No Litigation.There is no action, suit or proceeding pending or, to the best knowledge of
Debtor after reasonable investigation, threatened against Debtor that might adversely affect its
property or financial condition in any material respect.e.
    
    Ownership of Collateral.Debtor is the sole owner of and has good and marketable title to the
Collateral (or, in the case of after-acquired Collateral, at the time the Debtor acquires rights in
the Collateral, will be the sole owner thereof) and is the record and beneficial owner of any such
Collateral.f.
    
    Priority.Except for security interests in favor of Secured Party, no person has (or, in the
case of after-acquired Collateral, at the time Debtor acquires rights therein, will have) any
right, title, claim, or interest (by way of security interest or other lien or charge) in, against
or to the Collateral.g.
    
    Accuracy of Information.All information heretofore, herein or hereafter supplied to Secured
Party by or on behalf of Debtor with respect to the Collateral is true and correct.h.
    
    Delivery of Documents.Debtor has delivered to Secured Party all instruments, documents, chattel
paper, and other items of Collateral in which a security interest is or may be perfected by
possession, the certificate of title with respect to each motor vehicle, if any, included in the
Collateral, and any certificated Pledged Shares together with such additional writings, including,
without limitation, assignments and stock powers, with respect thereto as Secured Party shall
request.i.
    
    Exclusion of Certain Collateral.Unless otherwise agreed by Secured Party, the Collateral does
not include any aircraft, watercraft or vessels, railroad cars, railroad equipment, locomotives or
other rolling stock intended for a use related to interstate commerce, trade names, trademarks,
service marks, mask works, copyrights, patents, fixtures or uncertificated securities.
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j.
    
    Enforceability Against Account Debtors.Each account, contract right, item of chattel paper,
instrument or any other right to the payment of money constituting Collateral is genuine and
enforceable in accordance with its terms against the party obligated to pay the same (an Account
Debtor), which terms have not been modified or waived in any respect or to any extent.k.
    
    Amount Due From Account Debtors.Any amount represented by Debtor to Secured Party as owing by
any Account Debtor is the correct amount actually and unconditionally owing by such Account Debtor.l.
    
    No Account Debtor Defense.No Account Debtor has any defense, set off, claim, or counterclaim
against Debtor that can be asserted against Secured Party, whether in any proceeding to enforce
Secured Partys rights in the Collateral, or otherwise.
 5.
    
    Covenants and Agreements of DebtorIn addition to all covenants and agreements of Debtor set forth in the Credit Documents, which are
incorporated herein by this reference, Debtor hereby agrees:
 a.
    
    Preservation of Collateral.To do all acts that may be necessary to maintain, preserve, and
protect the Collateral.b.
    
    Use of Collateral.Not to use or permit any Collateral to be used unlawfully or in violation of
any provision of this Security Agreement, any other agreement with Secured Party related hereto or
any applicable statute, regulation, or ordinance or any policy of insurance covering the
Collateral.c.
    
    Payment of Taxes.To pay promptly when due all taxes, assessments, charges, encumbrances and
liens now or hereafter imposed upon or affecting any Collateral.d.
    
    Defense of Litigation.To appear in and defend any action or proceeding that may affect
its title to or Secured Partys interest in the Collateral.e.
    
    Possession of Collateral.Not to surrender or lose possession of (other than to Secured Party),
sell, encumber, lease, rent, or otherwise dispose of or transfer any Collateral or right or
interest therein except as hereinafter provided, and to keep the Collateral free of all levies and
security interests or other liens or charges except those approved in writing by Secured Party.f.
    
    Compliance with Law.To comply with all laws, regulations, and ordinances relating to the
possession, operation, maintenance, and control of the Collateral.
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g.
    
    Standard of Care by Secured Party.That such care as Secured Party gives to the safekeeping of
its own property of like kind shall constitute reasonable care of the Collateral when in Secured
Partys possession.h.
    
    Maintenance of Records.To keep separate, accurate, and complete records of the Collateral and
to provide Secured Party with such records and such other reports and information relating to the
Collateral as Secured Party may request from time to time.i.
    
    Further Assurances.To procure, execute, and deliver from time to time any endorsements,
notifications, registrations, assignments, financing statements, certificates of title, ship
mortgages, aircraft mortgages, copyright mortgages assignments or mortgages of patents, mortgages
of mask works, mortgages for filing pursuant to the Interstate Commerce Act, and other writings
deemed necessary or appropriate by Secured Party to perfect, maintain, and protect its security
interest in the Collateral hereunder and the priority thereof; and to take such other actions as
Secured Party may request to protect the value of the collateral and of Secured Partys security
interest in the Collateral, including, without limitation, provision of assurances from third
parties regarding Secured Partys access to, right to foreclose on or sell, Collateral and right to
realize the practical benefits of such foreclosure or sale.j.
    
    Payment of Secured Partys Costs and Expenses.To reimburse Secured Party upon demand for any
costs and expenses, including, without limitation, attorney fees and disbursements, Secured Party
may incur in preparing the Credit Documents and while exercising any right, power, or remedy
provided by this Security Agreement or by law, all of which costs and expenses are included in the
Obligations.k.
    
    Notification Regarding Certain Types of Collateral.To promptly notify Secured Party of
inclusion in the Collateral after the date hereof of any aircraft, watercraft or vessels, railroad
cars, railroad equipment, locomotives or other rolling stock intended for a use related to
interstate commerce, trade names, trademarks, service marks, mask works, copyrights, patents,
fixtures, or uncertificated securities.l.
    
    Notice of Changes.To give Secured Party thirty (30) days prior written notice of any change in
Debtors residence or chief place of business or legal name or tradename(s) or style(s) set forth
in the penultimate paragraph of this Security Agreement.m.
    
    Location of Records.To keep the records concerning the collateral at the location(s) set forth
in the penultimate paragraph of this Security Agreement and not to remove such records from such
location(s) without the prior written consent of the Secured Party.
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n.
    
    Purchase Money Agreement.If Secured Party gives value to enable Debtor to acquire
rights in or the use of any Collateral, to use such value for such purpose.
 6.
    
    Authorized Action by Secured PartyDebtor hereby agrees that from time to time, without presentment, notice or demand, and
without affecting or impairing in any way the rights of Secured Party with respect to the
Collateral, the obligations of the Debtor hereunder or the Obligations, Secured Party may,
but shall not be obligated to and shall incur no liability to Debtor or any third party for
failure to take any action which Debtor is obligated by this Security Agreement to do and
to exercise such rights and powers as Debtor might exercise with respect to the
Collateral, and Debtor hereby irrevocably appoints Secured Party as its attorney-in-fact to
exercise such rights and powers, including without limitation, to (a) file a financing
statement describing the Collateral, without the signature of either the Debtor or the
Secured Party; (b) collect by legal proceedings or otherwise and indorse, receive and
receipt for all dividends, interest, payments, proceeds, and other sums and property now or
hereafter payable on or on account of the Collateral; (c) enter into any extension,
reorganization, deposit, merger, consolidation, or other agreement pertaining to, or
deposit, surrender, accept, hold, or apply other property in exchange for the Collateral;
(d) insure, process, and preserve the Collateral; (e) transfer the Collateral to its own or
its nominees name; (f) make any compromise or settlement, and take any action it deems
advisable, with respect to the Collateral; and (g) notify any Account Debtor on any
Collateral to make payment directly to Secured Party.7.
    
    DefaultA default under this Security Agreement shall be deemed to exist upon the occurrence of any
of the following (an Event of Default):
 a.
    
    Default in Payment.Any of the Obligations shall not be paid in accordance with the
terms of the Credit Documents.b.
    
    Default under Credit Documents.Debtor shall fail to observe any other term or condition
of the Credit Documents or there shall otherwise occur any event which would permit Secured
Party to accelerate amounts outstanding thereunder or the Borrower shall fail to make any
payment or there shall otherwise occur any event which would permit Secured Party to
accelerate amounts outstanding to Borrower which are guaranteed by Debtor pursuant to the
Credit Documents.
 8.
    
    RemediesUpon the occurrence of any such Event of Default, Secured Party may, at its option, and
without notice to or demand on Debtor and in addition to all rights and remedies
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available to Secured Party under the Credit Documents, at law, in equity, or otherwise, do
any one or more of the following:
 a.
    
    General Enforcement.Foreclose or otherwise enforce Secured Partys security interest in
any manner permitted by law, or provided for in this Security Agreement.b.
    
    Sale, etc.Sell, lease, or otherwise dispose of any Collateral at one or more public or
private sales at Secured Partys place of business or any other place or places, including,
without limitation, any brokers board or securities exchange, whether or not such
Collateral is present at the place of sale, for cash or credit or future delivery, on such
terms and in such manner as Secured Party may determine.c.
    
    Costs of Remedies.Recover from Debtor all costs and expenses, including, without
limitation, reasonable attorney fees, incurred or paid by Secured Party in exercising any
right, power, or remedy provided by this Security Agreement.d.
    
    Manner of Sale of Collateral.Debtor shall be given ten (10) business days prior notice
of the time and place of any public sale or of the time after which any private sale or
other intended disposition of Collateral is to be made, which notice Debtor hereby agrees
shall be deemed reasonable notice thereof.e.
    
    Delivery to and Rights of Purchaser.Upon any sale or other disposition pursuant to this
Security Agreement, Secured Party shall have the right to deliver, assign, and transfer to
the purchaser thereof the Collateral or portion thereof so sold or disposed of. Each
purchaser at any such sale or other disposition (including Secured Party) shall hold the
Collateral free from any claim or right of whatever kind, including any equity or right of
redemption of Debtor and Debtor specifically waives (to the extent permitted by law) all
rights of redemption, stay or appraisal which it has or may have under any rule of law or
statute now existing or hereafter adopted.
 9.
    
    Cumulative RightsThe rights, powers, and remedies of Secured Party under this Security Agreement shall be in
addition to all rights, powers, and remedies given to Secured Party by virtue of any
statute or rule of law, the Credit Documents or any other agreement, all of which rights,
powers, and remedies shall be cumulative and may be exercised successively or concurrently
without impairing Secured Partys security interest in the Collateral.10.
    
    WaiverAny waiver, forbearance or failure or delay by Secured Party in exercising any right,
power, or remedy shall not preclude the further exercise thereof, and every right, power,
or remedy of Secured Party shall continue in full force and effect until such right, power
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or remedy is specifically waived in a writing executed by Secured Party. Debtor waives any
right to require Secured Party to proceed against any person or to exhaust any Collateral
or to pursue any remedy in Secured Partys power.11.
    
    SetoffDebtor agrees that Secured Party may exercise its rights of setoff with respect to the
Obligations in the same manner as if the Obligations were unsecured.12.
    
    Binding Upon SuccessorsAll rights of Secured Party under this Security Agreement shall inure to the benefit of its
successors and assigns, and all obligations of Debtor shall bind its heirs, executors,
administrators, successors, and assigns.13.
    
    Entire Agreement; SeverabilityThis Security Agreement contains the entire security agreement between Secured Party and
Debtor. If any of the provisions of this Security Agreement shall be held invalid or
unenforceable, this Security Agreement shall be construed as if not containing those
provisions and the rights and obligations of the parties hereto shall be construed and
enforced accordingly.14.
    
    Choice of LawThis Security Agreement shall be construed in accordance with and governed by the laws of
Texas, without giving effect to choice of law rules, and, where applicable and except as
otherwise defined herein, terms used herein shall have the meanings given them in the
Uniform Commercial Code of such state.15.
    
    AmendmentThis Security Agreement may not be amended or modified except by a writing signed by each
of the parties hereto.16.
    
    Residence; Collateral Location RecordsDebtor represents that its residence or chief place of business is set forth below its
signature hereto; and that, except as otherwise disclosed to Secured Party in writing prior
to the date hereof, the Collateral and Debtors records concerning the Collateral are
located at that address.
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17.
    
    Addresses for NoticesAll demands, notices, and other communications to Debtor or Secured Party provided for hereunder
shall be in writing or by telephone, promptly confirmed in writing, mailed, delivered, or sent by
telefacsimile, addressed or sent to it to the address or telefacsimile number, as the case may be,
of Debtor or Secured Party set forth beneath such partys signature below, or to such other address
as shall be designated by a party in a written notice to the other party. All such demands,
notices, and other communications shall, when mailed or sent by telefacsimile, be effective when
deposited in the mails, delivered or so sent, as the case may be, addressed as aforesaid.EXECUTEDthis 30th day of June 2011.
 DEBTOR:Address: 
508 West Wall Street, Suite 800
Midland, Texas 79701
    
    DAWSON GEOPHYSICAL COMPANYBy:
    
    /s/ Stephen C. JumperStephen C. Jumper 
PresidentBy:
    
    /s/ Christina W. HaganChristina W. Hagan 
SecretarySECURED PARTY:WESTERN NATIONAL BANK508 West Wall Street, Suite 1100
Midland, Texas 79701By:
    
    /s/ Wesley D. BowndsWesley D. Bownds 
President
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