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Registration Statement No. 333-                    

SECURITIES AND EXCHANGE COMMISSION

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Form S-3

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

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Dawson Geophysical Company

508 West Wall, Suite 800
Midland, Texas 79701
(432) 684-3000
(Address, including zip code, and telephone number,
including area code, of registrants’ principal executive offices)

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L. Decker Dawson
Chief Executive Officer
Dawson Geophysical Company
508 West Wall, Suite 800
Midland, Texas 79701
(432) 684-3000
(Name, address, including zip code, and telephone number,
including area code, of agent for service)
Copies to:

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     Approximate date of commencement of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective.

     If any of the securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

     If any of the securities being registered on this Form are being offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: o

     If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. x Registration No. 333-121236

     If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

     If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. o

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(1)	Includes 9,500 shares issuable upon exercise of the Underwriters’ over-allotment option. Does not include an aggregate of 1,725,000 shares of common stock registered by Dawson Geophysical Company on its registration statement on Form S-3 (Registration No. 333-121236) for the same offering.

(2)

In accordance with Rule 462(b) under the Securities Act of 1993, as amended, an additional amount of securities having a proposed maximum offering price of no more than 20% of the proposed maximum aggregate offering price ($37,924,125) of the 1,725,000 shares of common stock eligible to be sold under the registrant’s Registration Statement on Form S-3 (File No. 333-121236) is registered hereby.

     Pursuant to Rule 429 under the Securities Act of 1933, the prospectus also relates to the securities registered pursuant to the prior registration statement on Form S-3 (File No. 333-121236).

     This Registration Statement shall become effective upon filing with the Commission in accordance with Rule 462(b) under the Securities Act of 1933.

 

Explanatory Note and
Incorporation by Reference of Registration Statement on Form S-3 Registration No. 333-121236

     This Registration Statement on Form S-3 of Dawson Geophysical Company (the “Company”) is being filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended, and General Instruction IV to Form S-3. The Company hereby incorporates by reference into this Registration Statement on Form S-3 in its entirety the Registration Statement on Form S-3 (Registration No. 333-121236), relating to the offering of 1,725,000 shares of common stock, which was declared effective on February 28, 2005 by the Securities and Exchange Commission (the “Commission”), including each of the documents filed by the Company with the Commission and incorporated or deemed to be incorporated by reference therein. This Registration Statement is filed solely for the purpose of registering an additional 309,500 shares of the Company’s common stock.

 

SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Midland, State of Texas, on March 1, 2005.

	DAWSON GEOPHYSICAL COMPANY.
	By:	/s/ L. Decker Dawson
		Name:	L. Decker Dawson
		Title:	Chairman of the Board of Directors and Chief Executive Officer

     Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed below by the following persons in the capacities and on the dates indicated below.

*By: /s/ Stephen C. Jumper
     Stephen C. Jumper
     Attorney-in-Fact

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INDEX TO EXHIBITS

* Filed herewith.

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