DAWSON GEOPHYSICAL CO — Director's Dealing 2005

May 26, 2005

SEC Form 4/A — Form 4/A

Issuer: TGC INDUSTRIES INC (TGCI)
CIK: 0000799165
Period of Report: 2004-12-10

Reporting Person: HURTT WILLIAM C JR (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2004-12-10	Common Stock	P	1000	$2.91	Acquired	391500	Direct
2005-01-13	Common Stock	P	500	$2.98	Acquired	392000	Direct
2005-01-13	Common Stock	P	1500	$3.00	Acquired	393500	Direct
2005-01-28	Common Stock	P	1000	$3.00	Acquired	394500	Direct
2005-01-31	Common Stock	P	5000	$2.80	Acquired	399500	Direct
2005-02-01	Common Stock	P	9000	$2.82	Acquired	408500	Direct
2005-02-03	Common Stock	P	200	$2.90	Acquired	408700	Direct

Footnotes

F1: Includes 15,700 shares of common stock held in Reporting Person's IRA.

F2: These shares were reported as a single purchase of 18,000 shares for $2.80 per share on February 4, 2005, on the reporting person's original Form 4.

F3: These shares were reported as being purchased on February 4, 2005, on the reporting person's original Form 4.