DAWSON GEOPHYSICAL CO — Director's Dealing 2005

Feb 2, 2005

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TGC INDUSTRIES INC (TGCI)
CIK: 0000799165
Period of Report: 2005-01-31

Reporting Person: Winn Daniel G (Vice President)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2005-01-31	Common Stock	S	3900	$2.81	Disposed	100	Direct

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Option	$1	2005-12-10	Common Stock (10000)	10000	Direct
Stock Option	$0.8	2009-02-19	Common Stock (8000)	8000	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.