DAWSON GEOPHYSICAL CO — Director's Dealing 2004

Sep 10, 2004

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TGC INDUSTRIES INC (TGCI)
CIK: 0000799165
Period of Report: 2004-09-08

Reporting Person: WHITENER WAYNE A (Director, President and CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2004-09-08	Common Stock	S	4000	$1.65	Disposed	60447	Direct
2004-09-08	Common Stock	S	100	$1.7	Disposed	60347	Direct
2004-09-09	Common Stock	S	3400	$1.65	Acquired	56947	Direct

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Option	$1	2005-12-10	Common Stock (50000)	50000	Direct
Stock Option	$0.8	2009-02-19	Common Stock (50000)	50000	Direct
Warrant	$0.3	2009-07-31	Common Stock (50000)	50000	Direct

Footnotes

F1: Stock options are exercisable as follows: one-third exercisable after twelve months from date of grant; two-thirds exercisable after twenty-four months from date of grant; and all exercisable after thirty-six months from date of grant.

F2: Warrants issued as a bonus.