DAWSON GEOPHYSICAL CO — Director's Dealing 2008

Oct 27, 2008

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TGC INDUSTRIES INC (TGCI)
CIK: 0000799165
Period of Report: 2007-09-19

Reporting Person: BARRETT WILLIAM J (Director, 10% Owner)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2007-09-19	Nonqualified Stock Option	$9.24	A	9493	Acquired	2012-09-18	Common Stock (9968)	Direct
2008-10-23	Nonqualified Stock Option	$3.41	A	22059	Acquired	2013-10-22	Common Stock (22059)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	1625101	Direct
Common Stock	146041	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Option (reload)	$6.81	2010-10-10	Common Stock (1615)	1615	Direct

Footnotes

F1: The Reporting Person disclaims beneficial ownership of common stock owned by spouse.

F2: Not applicable.

F3: Adjusted for the Company's 5% stock dividends paid to all holders of record of common stock on April 27, 2007 and April 28, 2008.

F4: Currently exercisable.

F5: The option vests in two equal installments beginning on 10-23-2008.