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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 MRdaTUd4LhAdEXxSPm6I1aP2Z1re6+TQ7GxicNeXDql8SpA5k8sgIMa6iC8LhfUa
 uBCsKq/YfLkzbI4YaWAWCw==

<SEC-DOCUMENT>0001179110-08-002679.txt : 20080207
<SEC-HEADER>0001179110-08-002679.hdr.sgml : 20080207
<ACCEPTANCE-DATETIME>20080207181529
ACCESSION NUMBER:		0001179110-08-002679
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20071231
FILED AS OF DATE:		20080207
DATE AS OF CHANGE:		20080207

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GARDNER HERBERT M
		CENTRAL INDEX KEY:			0000923414

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32472
		FILM NUMBER:		08586366

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		2125100684

	MAIL ADDRESS:	
		STREET 1:		P O BOX 6199
		CITY:			FAIR HAVEN
		STATE:			NJ
		ZIP:			07704

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TGC INDUSTRIES INC
		CENTRAL INDEX KEY:			0000799165
		STANDARD INDUSTRIAL CLASSIFICATION:	OIL AND GAS FIELD EXPLORATION SERVICES [1382]
		IRS NUMBER:				742095844
		STATE OF INCORPORATION:			TX
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1304 SUMMIT AVE STE 2
		CITY:			PLANO
		STATE:			TX
		ZIP:			75074
		BUSINESS PHONE:		9728811099

	MAIL ADDRESS:	
		STREET 1:		1304 SUMMIT AVE
		STREET 2:		STE 2
		CITY:			PLANO
		STATE:			TX
		ZIP:			75074
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 5 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2007-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000799165</issuerCik>
        <issuerName>TGC INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>TGE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000923414</rptOwnerCik>
            <rptOwnerName>GARDNER HERBERT M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P O BOX 6199</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FAIR HAVEN</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07704</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-06-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>220000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>291960</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>220000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By GRAT</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>60040</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Spouse</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On June 12, 2007, the reporting person contributed 220,000 shares of TGC common stock to a GRAT of which the reporting person's spouse is a trustee and of which the reporting person and his wife are beneficiaries.  The reporting person continues to report beneficial ownership of all of the TGC common stock held by the GRAT, but disclaims beneficial ownership except to the extent of his and his wife's pecuniary interest therein.</footnote>
        <footnote id="F2">Not applicable</footnote>
        <footnote id="F3">Reporting person disclaims beneficial ownership of shares owned by spouse.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Herbert M. Gardner</signatureName>
        <signatureDate>2008-02-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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