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Table of Contents

As filed with the Securities and Exchange Commission on November 6,December 30, 2014.

Registration No. 333-          333-199922


UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549



Amendment No. 2
to
FORM S-4
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933



TGC Industries, Inc.
(Exact name of registrant as specified in its charter)

Texas
(State or other jurisdiction of
incorporation or organization)
 1382
(Primary Standard Industrial
Classification Code Number)
 74-2095844
(I.R.S. Employer
Identification Number)



101 E. Park Blvd., Suite 955
Plano, TX 75074
(972) 881-1099

(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)



Wayne A. Whitener
President and Chief Executive Officer
TGC Industries, Inc.
101 E. Park Blvd., Suite 955
Plano, Texas 75074
(972) 881-1099

(Name, address, including zip code, and telephone number, including area code, of agent for service)



Copies to:

W. Scott Wallace
Jennifer T. Wisinski
Haynes and Boone, LLP
2323 Victory Avenue, Suite 700
Dallas, Texas 75219
(214) 651-5000

 

Stephen C. Jumper
President and Chief Executive Officer
Dawson Geophysical Company
508 West Wall, Suite 800
Midland, Texas 79701
(432) 684-3000

 

Neel Lemon
Chad Burkhardt
Baker Botts L.L.P.
2001 Ross Avenue, Suite 1100
Dallas, Texas 75201
(214) 953-6500

Approximate date of commencement of the proposed sale of the securities to the public:
As soon as practicable after this registration statement becomes effective and upon completion of the merger described in the enclosed document.

             If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, 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, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

             If this Form is a post-effective amendment filed pursuant to Rule 462(d) 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

             Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act:

Large accelerated filer o Accelerated filer ý Non-accelerated filer o
(Do not check if a
smaller reporting company)
 Smaller reporting company o

             If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

             Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer)    o

             Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)    o

CALCULATION OF REGISTRATION FEE

        
 
Title of each class of securities
to be registered(1)

 Amount to be
registered(2)

 Proposed maximum
offering price per
share

 Proposed maximum
aggregate offering
price(3)

 Amount of
registration fee(4)

 

Common Stock, par value $0.01 per share

 14,418,554 N/A $134,027,010 $15,573.94

 

(1)
This registration statement relates to shares of common stock, par value $0.01 per share, of TGC Industries, Inc., a Texas corporation, which we refer to as TGC, issuable to holders of common stock, par value $0.33 1/3 per share, of Dawson Geophysical Company, a Texas corporation, which we refer to as Dawson, in the proposed merger of Riptide Acquisition Corp., a Texas corporation and a direct, wholly owned subsidiary of TGC, which we refer to as Merger Sub, with and into Dawson.

(2)
Based on the maximum number of shares of TGC's common stock estimated to be issued pursuant to the merger agreement, on a post-reverse stock split basis, calculated as the product of (a) 8,192,360 shares, the estimated number of shares of Dawson common stock that may be cancelled and exchanged in the merger (based on the number of shares outstanding as of November 4, 2014, and assuming the exercise of all outstanding Dawson stock options and including all outstanding shares of Dawson restricted stock and restricted stock units, for an aggregate of 113,127 additional shares of Dawson common stock and 14,000 shares of restricted stock and restricted stock units that may be issued by Dawson prior to consummation of the merger and (b) the stock exchange ratio, which is 1.760 (after giving effect to the 1-for-3 reverse stock split of TGC common stock).

(3)
Estimated solely for the purpose of calculating the registration fee required by Section 6(b) of the Securities Act of 1933, as amended, which we refer to as the Securities Act, and calculated pursuant to Rule 457(f) under the Securities Act. Pursuant to Rule 457(f)(1) under the Securities Act, the proposed maximum aggregate offering price of TGC's common stock was calculated based upon the market value of shares of Dawson common stock (the securities to be cancelled in the merger) in accordance with Rule 457(c) under the Securities Act as follows: the product of (a) $16.36, the average of the high and low prices per share of Dawson common stock on November 4, 2014, as reported on the Nasdaq Stock Market and (b) 8,192,360 shares of Dawson common stock, the maximum total number of shares of Dawson common stock that may be cancelled in the merger.

(4)
Represents the product of (a) 0.0001162 and (b) the proposed maximum aggregate offering price for shares of Dawson common stock.

             If, as a result of stock splits, stock dividends or similar transactions, the number of securities purported to be registered on the registration statement changes, the provisions of Rule 416 shall apply to the registration statement.

             The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until this registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to Section 8(a), may determine.

   


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The information in this preliminary joint proxy statement/prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary joint proxy statement/prospectus is not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED NOVEMBER 6,DECEMBER 30, 2014

PROPOSED MERGER—YOUR VOTE IS VERY IMPORTANT


LOGO

 
LOGO

To the shareholders of Dawson Geophysical Company and TGC Industries, Inc.:

           On October 8, 2014, Dawson Geophysical Company, or Dawson, and TGC Industries, Inc., or TGC, announced our proposed strategic business combination. The boards of directors of Dawson and TGC have each approved an agreement and plan of merger, a copy of which is attached as Annex A to this joint proxy statement/prospectus, as such agreement may be amended from time to time, or the merger agreement, pursuant to which Riptide Acquisition Corp., or Merger Sub, a newly formed wholly owned subsidiary of TGC, will be merged with and into Dawson, with Dawson surviving the merger as a direct wholly owned subsidiary of TGC, or the merger. Immediately prior to the merger, TGC will change its name to "Dawson Geophysical Company" and Dawson will change its name to "Dawson Operating Company."

           This joint proxy statement/prospectus describes the terms of the merger agreement and the merger, including the reasons the merger was proposed, the negotiation process that led to entry into the merger agreement and other background information. We are sending you this joint proxy statement/prospectus and related materials in connection with the solicitation of proxies by the boards of directors of Dawson and TGC for use at their special meetings of shareholders, both to be held on [                        ].February 9, 2015. At the special meetings, among other items, the shareholders of Dawson and TGC will be asked to approve certain proposals that are required to effect the merger. These proposals are discussed in greater detail in the remainder of this joint proxy statement/prospectus. We urge you to read carefully this joint proxy statement/prospectus and the documents incorporated by reference into it.

           Immediately prior (and as a condition precedent) to completion of the merger, TGC will undertake a reverse stock split with respect to the TGC common stock on a 1-for-3 ratio. If the proposed merger is completed, then pursuant to the merger agreement, each holder of shares of Dawson common stock will be entitled to receive 1.760 shares of TGC common stock for each share of Dawson common stock owned, after giving effect to the proposed reverse stock split, as well as cash payable in lieu of fractional shares pursuant to the terms of the merger agreement.

           We anticipate that, immediately following completion of the merger (and after giving effect to the proposed reverse stock split), current Dawson shareholders will own approximately 66% of the outstanding shares of TGC common stock and TGC shareholders will own approximately 34% of the outstanding shares of TGC common stock.

           TGC shareholders will continue to own their existing shares of TGC common stock, however, the number of shares they hold will be adjusted downward pursuant to the proposed reverse stock split. Following the reverse stock split, registered holders of TGC common stock who hold stock certificates or shares in book-entry form will be sent a letter of transmittal from TGC's transfer agent that contains instructions for surrendering pre-reverse stock split shares to the transfer agent in exchange for the appropriate number of post-reverse stock split shares in book-entry form (or certificated form if requested). Dawson's common stock is currently listed on NASDAQ under the symbol "DWSN." TGC's common stock is currently listed on NASDAQ under the symbol "TGE" and, following the merger and the change of TGC's name to "Dawson Geophysical Company," is expected to be listed on NASDAQ under the symbol "DWSN."

           Dawson is holding a special meeting of its shareholders to approve (i) the merger agreement, or the merger proposal, (ii) an amendment to Dawson's second restated articles of incorporation to change Dawson's name to "Dawson Operating Company" immediately prior to the merger, or the Dawson name change proposal, (iii) a non-binding advisory resolution on certain compensation that may be paid or become payable to Dawson's named executive officers upon consummation of the merger, or the advisory resolution proposal and (iv) adjournments of the special meeting, if necessary or appropriate, to permit the solicitation of additional proxies if there are not sufficient votes at the time of the special meeting to adopt the foregoing proposals, or the Dawson adjournment proposal. Certain executive officers and directors of Dawson who beneficially own, in the aggregate, approximately 2.40%2.39% of the currently outstanding shares of Dawson common stock have entered into a voting agreement with TGC. Pursuant to and subject to the terms of the voting agreement, those directors and executive officers have agreed, among other things, to vote their shares of Dawson common stock in favor of the merger proposal.

           TGC is holding a special meeting of its shareholders to approve (i) the issuance of shares of TGC common stock in connection with the proposed merger, or the share issuance proposal, (ii) an amendment to TGC's amended and restated certificate of formation to effectuate a 1-for-3 reverse stock split with respect to TGC common stock to take effect immediately prior to the merger, or the reverse stock split proposal, (iii) an amendment to TGC's amended and restated certificate of formation to change TGC's name to "Dawson Geophysical Company" immediately prior to the merger, or the TGC name change proposal, and (iv) adjournments of the special meeting, if necessary or appropriate, to permit the solicitation of additional proxies if there are not sufficient votes at the time of the special meeting to adopt the foregoing proposals, or the TGC adjournment proposal. Certain executive officers and directors of TGC and their affiliates who beneficially own, in the aggregate, approximately 29.05%28.84% of the shares of TGC common stock, or 27.59%27.60% of the shares of TGC common stock currently outstanding and entitled to vote as of November 5,December 29, 2014, have entered into voting agreements with Dawson. Pursuant to and subject to the terms of those voting agreements, those directors and executive officers and their affiliates have agreed, among other things, to vote their shares of TGC common stock in favor of the share issuance proposal, the reverse stock split proposal, the TGC name change proposal and the TGC adjournment proposal, each in connection with the proposed merger, at the TGC special meeting.

           The obligations of Dawson and TGC to complete the merger are subject to the satisfaction or waiver of several conditions. We cannot complete the merger unless, among other things:

           All Dawson and TGC shareholders are invited to attend their company's special meeting in person.Your vote is very important, regardless of the number of shares you own. Whether or not you expect to attend either special meeting in person, please submit a proxy to vote your shares as promptly as possible so that your shares may be represented and voted at the Dawson or TGC special meeting, as applicable, by signing, dating and returning the enclosed proxy card, by calling the toll-free telephone number, or by submitting over the Internet as described in the instructions included with your proxy card.

           This document is a prospectus relating to the shares of TGC common stock to be issued pursuant to the merger and a proxy statement for each of Dawson and TGC to solicit proxies for their respective special meetings of shareholders. This document contains answers to frequently asked questions and a summary of the important terms of the merger, the merger agreement and related matters, followed by a more detailed discussion.

           For a discussion of certain significant matters that you should consider before voting, see "Risk Factors" beginning on page 45.43.

           We look forward to the successful completion of the merger.

Sincerely,
Stephen C. Jumper
President and Chief Executive Officer
Dawson Geophysical Company
 Sincerely,
Wayne A. Whitener
President and Chief Executive Officer
TGC Industries, Inc.

           Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the TGC common stock to be issued pursuant to the merger or passed upon the adequacy or accuracy of this joint proxy statement/prospectus. Any representation to the contrary is a criminal offense.

           This joint proxy statement/prospectus is dated [                        ]December 30, 2014 and is first being mailed to shareholders on or about [                        ].December 31, 2014.


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ADDITIONAL INFORMATION

Dawson

        This joint proxy statement/prospectus incorporates important business and financial information about Dawson from other documents that are not included in or delivered with this joint proxy statement/prospectus. This information is available to you without charge upon your request. You can review documents incorporated by reference in this joint proxy statement/prospectus free of charge through the Securities and Exchange Commission, or the SEC, website (http://www.sec.gov). You can also obtain the documents incorporated by reference into this document by requesting them in writing or by telephone from Dawson at the following addresses and telephone numbers:

Dawson Geophysical Company
508 West Wall, Suite 800
Midland, Texas 79701
Telephone: (432) 684-3000

or

Morrow & Co., LLC
470 West Avenue, 3rd Floor
Stamford, CT 06902
Banks and brokers call collect: (203) 658-9400
Shareholders Please Call Toll Free: (800) 662-5200

        You will not be charged for any of the documents that you request. Shareholders requesting documents should do so by [            ],Monday, February 2, 2015, in order to receive them before the applicable special meeting.


TGC

        This joint proxy statement/prospectus includes important business and financial information about TGC. Additional information about TGC is available to you without charge upon your request. You can review documents that TGC files with the SEC through the SEC's website (http://www.sec.gov). You can also obtain the documents that TGC files with the SEC by requesting them in writing or by telephone at the following addresses and telephone numbers:

TGC Industries, Inc.
101 E. Park Blvd., Suite 955
Plano, Texas 75074
Telephone: (972) 881-1099

or

D.F. King & Co., Inc.
48 Wall Street, 22nd Floor
New York, New York 10005
Banks and brokers call collect: (212) 269-5550
Shareholders Please Call Toll Free: (877) 283-0322

        You will not be charged for any of the documents that you request. Shareholders requesting documents should do so by [            ],Monday, February 2, 2015, in order to receive them before the applicable special meeting.

        For more information, see "Where You Can Find More Information" beginning on page 228.225.

        This document does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction. Information contained in this document regarding Dawson has been provided by Dawson and information contained in this document regarding TGC has been provided by TGC.


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VOTING BY TELEPHONE, INTERNET OR MAIL

Shareholders of record of either Dawson or TGC may submit their proxies by:

        Telephone.    You can vote by telephone by calling the toll-free number [                      ]1-800-690-6903 in the United States, Canada or Puerto Rico on a touch-tone telephone. You will then be prompted to enter the control number printed on either Dawson's or TGC's proxy card, as applicable, and to follow the subsequent instructions. Telephone voting is available 24 hours a day until 11:59 p.m., New York City time, on [                      ].Sunday, February 8, 2015. If you vote by telephone, you do not need to return your proxy card or voting instruction card.

        Internet.    You can vote over the Internet by accessing the website at [                      ]www.proxyvote.com and following the instructions on the secure website. Internet voting is available 24 hours a day until 11:59 p.m., New York City time, on [                      ].Sunday, February 8, 2015. If you vote over the Internet, you do not need to return your proxy card or voting instruction card.

        Mail.    You can vote by mail by completing, signing, dating and mailing your proxy card or voting instruction card in the postage-paid envelope included with this joint proxy statement/prospectus.


If you hold your shares through a bank, broker, custodian or other record holder:

        Please refer to your company's proxy card or voting instruction form or the information forwarded by your bank, broker, custodian or other record holder to see which voting methods are available to you.


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DAWSON GEOPHYSICAL COMPANY

508 West Wall, Suite 800
Midland, TX 79701
432-684-3000

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS
TO BE HELD ON [                    ]MONDAY, FEBRUARY 9, 2015

To the Shareholders of Dawson Geophysical Company:

        We will hold a special meeting of the shareholders of Dawson Geophysical Company, or Dawson, at the offices of Baker Botts L.L.P. at 2001 Ross Avenue, Suite 1100, Dallas, Texas 75201 at 8:3:00 a.m.p.m., central time, on [                    ]Monday, February 9, 2015 for the following purposes:

        Only holders of record of Dawson common stock at the close of business on [                    ],December 29, 2014, the record date for the special meeting, are entitled to receive this notice and to vote their shares at the special meeting or at any adjournment or postponement of the special meeting.

        We cannot complete the merger unless holders of at least two-thirds of all outstanding shares of Dawson common stock vote to approve the merger proposal and the Dawson name change proposal.

        For more information about the merger and the other transactions contemplated by the merger agreement, please review the accompanying joint proxy statement/prospectus and the merger agreement attached to it as Annex A.

        Dawson's board of directors recommends that Dawson shareholders vote "FOR" the merger proposal, "FOR" the Dawson name change proposal, "FOR" the advisory resolution proposal and "FOR" the Dawson adjournment proposal. In considering the recommendations of the Dawson board of directors, Dawson shareholders should be aware that members of Dawson's board of directors and its executive officers have agreements and arrangements that provide them with interests in the


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merger that are different from, or in addition to, those of Dawson shareholders. See "The Merger—Conflicts of Interests" beginning on page 124.122.

By Order of the Board of Directors,

SIG

Christina W. Hagan

Secretary

DATED this [    ]30th day of [                    ], [                    ]December, 2014

IMPORTANT

Your vote is important. Whether or not you plan to attend the special meeting, please complete, sign and date the enclosed proxy and return it promptly in the enclosed postage-paid envelope. You may also cast your vote by telephone or over the Internet by following the instructions on your proxy card. If you vote by telephone or over the Internet, you do not need to submit your proxy card.Remember, your vote is important, so please act today!


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TGC INDUSTRIES, INC.

101 E. Park Blvd., Suite 955
Plano, Texas 75074
(972) 881-1099

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

TO BE HELD ON [                    ]MONDAY, FEBRUARY 9, 2015

To the Shareholders of TGC Industries, Inc.:

        We will hold a special meeting of the shareholders of TGC Industries, Inc., or TGC, at the offices of Haynes and Boone, LLP at 2323 Victory Avenue, Suite 700, Dallas, Texas 75219 at 8:2:00 a.m.p.m., central time, on [                    ]Monday, February 9, 2015 for the following purposes:

        Only holders of record of TGC common stock at the close of business on [                    ],December 29, 2014, the record date for the special meeting, are entitled to receive this notice and to vote their shares at the special meeting or at any adjournment or postponement of the special meeting.

        We cannot complete the merger unless holders of (i) at least two-thirds of all outstanding shares of TGC common stock vote to approve the reverse stock split proposal and the TGC name change proposal and (ii) a majority of the outstanding shares of TGC common stock present in person or represented by proxy and entitled to vote and that voted for or against or expressly abstained with respect to the share issuance proposal, assuming a quorum is present, vote to approve such proposal.

        For more information about the merger and the other transactions contemplated by the merger agreement, please review the accompanying joint proxy statement/prospectus and the merger agreement attached to it as Annex A.

        TGC's board of directors recommends that TGC shareholders vote "FOR" the share issuance proposal, "FOR" the reverse stock split proposal, "FOR" the TGC name change proposal and "FOR" the TGC adjournment proposal. In considering the recommendations of the TGC board of directors, TGC shareholders should be aware that members of TGC's board of directors and its executive officers have agreements and arrangements that provide them with interests in the merger that are


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different from, or in addition to, those of TGC shareholders. See "The Merger—Conflicts of Interests" beginning on page 124.122.

By Order of the Board of Directors,

SIG

James K. Brata

Secretary

DATED this [      ]30th day of [                ], [        ]December, 2014

IMPORTANT

        Your vote is important. Whether or not you plan to attend the special meeting, please complete, sign and date the enclosed proxy and return it promptly in the enclosed postage-paid envelope. You may also cast your vote by telephone or over the Internet by following the instructions on your proxy card. If you vote by telephone or over the Internet, you do not need to submit your proxy card. Please do not send any stock certificates at this time.Remember, your vote is important, so please act today!


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TABLE OF CONTENTS

 
 Page 

QUESTIONS AND ANSWERS ABOUT THE MERGER

  1 

SUMMARY

  16 

The Parties to the Merger

  16 

The Merger

  17 

Reverse Stock Split

  17 

Name Change

  17 

Merger Consideration

  17 

The Number of Shares of TGC Common Stock to Be Issued in the Merger Is Fixed, and Therefore the Value of the Merger Consideration Will Fluctuate with the Market Price of TGC Common Stock

  17 

Treatment of Dawson Stock Options, Restricted Stock and Restricted Stock Units

  18 

Treatment of TGC Stock Options and Restricted Stock

  18 

Dawson's Reasons for the Merger

  18 

TGC's Reasons for the Merger

  19 

Recommendations of the Dawson Board of Directors

  19 

Recommendations of the TGC Board of Directors

  19 

Opinion of Raymond James & Associates, Inc., Financial Advisor to Dawson

  19 

Opinion of Stephens Inc., Financial Advisor to TGC

  20 

Ownership of TGC Following the Merger

  20 

Board of Directors and Management of TGC Following the Merger

  20 

The Dawson Special Meeting

  21 

The TGC Special Meeting

  21 

Record Date

  21 

Votes Required to Approve the Proposals

  22 

Description of TGC Capital Stock

  23 

Outstanding Shares and Share Ownership of Management

  23 

Conditions to Completion of the Merger

  23 

Regulatory Requirements

  24 

Termination of the Merger Agreement

  2425 

Termination Fee and Expense Reimbursement

  25 

Conflicts of Interests

  26 

Acquisition Proposals

  27 

Risk Factors

  28 

Material U.S. Federal Income Tax Consequences of the Merger

  28 

Accounting Treatment

  2829 

Listing of TGC Common Stock and Delisting and Deregistration of Dawson Common Stock

  2829 

Appraisal Rights

  29 

Comparison of Shareholder Rights

  29 

FINANCIAL SUMMARY

  30 

Selected Historical Financial Data of Dawson

  30 

Dawson Statement of Operations Data

  30 

Dawson Balance Sheet Data

  31 

Other Dawson Statement of Cash FlowsFinancial Data

  31 

Dawson Developments for Period Ended JuneSeptember 30, 2014

  31 

Dawson Reconciliation of EBITDA to Net Income (Loss)

  3332 

Selected Historical Consolidated Financial Data of TGC

  3433 

TGC Statement of Operations Data

  3433 

TGC Balance Sheet Data

  3534 

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 Page 

Other TGC Statement of Cash FlowsFinancial Data

  3534 

TGC Developments for Period Ended JuneSeptember 30, 2014

  3534 

TGC Reconciliation of EBITDA to Net Income

  3635 

Selected Unaudited Pro Forma Condensed Combined Consolidated Financial and Other Information

  3736 

COMPARATIVE PER SHARE MARKET PRICE AND DIVIDEND INFORMATION

  4039 

Dawson Historical Market Price Data and Dividends

  4039 

TGC Historical Market Price Data and Dividends

  4039 

Value of Merger Consideration

  4140 

Number of Record and Beneficial Owners

  4241 

UNAUDITED COMPARATIVE PER SHARE DATA

  4342 

RISK FACTORS

  4543 

Risks Related to the Merger

  4543 

Risks Related to Dawson

  5351 

Risks Related to TGC's Business

  5452 

Risks Related to TGC's Industry

  5654 

Risks Related to TGC's Common Stock

  5856 

CAUTIONARY STATEMENTS CONCERNING FORWARD-LOOKING STATEMENTS

  6058 

THE DAWSON SPECIAL MEETING

  6260 

Date, Time and Place

  6260 

Purpose

  6260 

Board Recommendations

  6260 

Record Date; Outstanding Shares; Shares Entitled to Vote

  6260 

Quorum

  6260 

Required Vote

  6361 

Tabulation of the Votes

  6361 

Stock Ownership of and Voting by Dawson's Directors and Executive Officers

  6361 

Voting of Shares by Holders of Record

  6462 

Voting of Shares Held in Street Name

  6462 

Revocability of Proxies; Changing Your Vote

  6563 

Solicitation of Proxies

  6563 

No Other Business

  6664 

Adjournments and Postponements

  6664 

Assistance

  6664 

DAWSON PROPOSAL 1—APPROVAL OF THE MERGER PROPOSAL

  6765 

DAWSON PROPOSAL 2—APPROVAL OF THE DAWSON NAME CHANGE PROPOSAL

  6866 

DAWSON PROPOSAL 3—THE ADVISORY RESOLUTION PROPOSAL

  6967 

DAWSON PROPOSAL 4—THE DAWSON ADJOURNMENT PROPOSAL

  7169 

THE TGC SPECIAL MEETING

  7270 

Date, Time and Place

  7270 

Purpose

  7270 

Board Recommendations

  7270 

Record Date; Outstanding Shares; Shares Entitled to Vote

  7270 

Quorum

  7270 

Required Vote

  7371 

Tabulation of the Votes

  7371 

Stock Ownership of and Voting by TGC's Directors and Executive Officers

  7371 

Voting of Shares by Holders of Record

  7371 

Voting of Shares Held in Street Name

  7472 

Revocability of Proxies; Changing Your Vote

  7573 

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 Page 

Solicitation of Proxies

  7573 

No Other Business

  7674 

Adjournments and Postponements

  7674 

Assistance

  7674 

TGC PROPOSAL 1—APPROVAL OF THE SHARE ISSUANCE PROPOSAL

  7775 

TGC PROPOSAL 2—APPROVAL OF THE REVERSE STOCK SPLIT PROPOSAL

  7876 

Overview

  7876 

Principal Effects of the Reverse Stock Split

  7876 

Fractional Shares

  7977 

Effect on Registered "Book-Entry" Shareholders and Registered Certificated Shareholders

  7977 

Effect on Beneficial Holders of Common Stock

  7977 

Procedure for Effecting Reverse Stock Split and Exchange of Stock Certificates

  8078 

Accounting Matters

  8078 

No Appraisal Rights

  8078 

Certificate of Amendment to Amended and Restated Certificate of Formation

  8078 

Conditions and Board Recommendation

  8179 

TGC PROPOSAL 3—APPROVAL OF THE TGC NAME CHANGE PROPOSAL

  8280 

Name Change

  8280 

TGC PROPOSAL 4—THE TGC ADJOURNMENT PROPOSAL

  8381 

THE PARTIES TO THE MERGER

  8482 

THE MERGER

  8684 

Overview

  8684 

Background of the Merger

  8684 

Dawson's Reasons for the Merger and Recommendation of Dawson's Board of Directors

  9593 

TGC's Reasons for the Merger and Recommendation of TGC's Board of Directors

  10098 

Certain Information Provided by the Parties

  104102 

Opinion of Dawson's Financial Advisor

  108106 

Opinion of TGC's Financial Advisor

  113111 

Stock Ownership of Directors and Executive Officers of Dawson and TGC

  121119 

Merger Consideration

  122120 

Accounting Treatment

  123121 

Listing of TGC Common Stock and Delisting and Deregistration of Dawson Common Stock

  123121 

Restrictions on Sales of Shares of TGC Common Stock Received in the Merger

  123121 

Opinions as to Material U.S. Federal Income Tax Consequences of the Merger

  123121 

Ownership of TGC Following the Merger

  124122 

Board of Directors and Management of TGC Following the Merger

  124122 

Conflicts of Interests

  124122 

Appraisal Rights

  130128 

Regulatory Requirements

  131128

Demand Letter

129 

Dividend Policy

  131129 

THE MERGER AGREEMENT

  132130 

Merger

  132130 

Effective Time; Closing

  132130 

Governance Matters

  133131 

Merger Consideration

  133131 

Effect of the Merger on Dawson's Equity Awards

  134132 

Effect of the Merger on TGC's Equity Awards

  134132 

Payment of Merger Consideration

  135133 

Representations and Warranties

  136

Definition of "Material Adverse Effect"

138134 

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 Page 

Definition of "Material Adverse Effect"

136

Covenants and Agreements

  139137 

Conditions to Completion of the Merger

  148146 

Termination of the Merger Agreement

  150148 

Termination Fee and Expense Reimbursement

  151149 

Amendments, Extensions and Waivers

152

Specific Performance

152

Governing Law

152

THE TGC SHAREHOLDER VOTING AGREEMENTS

153

No Disposition

153

Voting of Shares of TGC Common Stock

153

Irrevocable Proxy

154

Termination of the TGC Shareholder Voting Agreements

154

Shareholder Capacity

  154 

Specific Performance

  154 

Governing Law

  154 

THE TGCDAWSON SHAREHOLDER VOTING AGREEMENTSAGREEMENT

  155 

No Disposition

  155 

Voting of Shares of TGCDawson Common Stock

  155 

Irrevocable Proxy

  156155 

Termination of the TGCDawson Shareholder Voting AgreementsAgreement

  156 

Shareholder Capacity

  156 

Specific Performance

  156 

Governing Law

  156 

THE DAWSON SHAREHOLDER VOTING AGREEMENTEMPLOYMENT AGREEMENTS

  157 

No DispositionTerm

  157

Voting of Shares of Dawson Common Stock

157

Irrevocable Proxy

157

Termination of the Dawson Shareholder Voting Agreement

158

Shareholder Capacity

158

Specific Performance

158

Governing Law

158

THE EMPLOYMENT AGREEMENTS

159

Term

159 

Duties and Compensation

  159157 

Termination of the Employment Agreements

  160158 

Payment upon Termination

  161159 

Restrictive Covenants

  162160 

Arbitration

  162160 

Governing Law

  163161 

Description of Specific Employment Agreements

  163161 

INFORMATION ABOUT TGC

  164162 

Description of Business

  164162 

General

  164162 

Description of Property

  168166 

Legal Proceedings

  168166 

Market Price of and Dividends on TGC's Common Equity and Related Stockholder Matters

  168166 

Selected Financial Data

  169167 

Management's Discussion and Analysis of Financial Condition and Results of Operations

  169167 

Recently Issued Accounting Pronouncements

  180179 

Quantitative and Qualitative Disclosures About Market Risk

  181180 

Financial Statements and Supplementary Data

  182181 

Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

  182181 

Directors, Executive Officers and Corporate Governance

  182181 

Compensation Discussion and Analysis

  185184 

Compensation Information

  188187 

Transactions with Related Persons, Promoters and Certain Control Persons

  195194 

Security Ownership of Certain Beneficial Owners and Management

  196

MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER

198195 

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 Page 

MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER

197

General

  198197 

Qualification of the Merger as a Reorganization

  199198 

Material U.S. Federal Income Tax Consequences if the Merger Fails to Qualify as a Reorganization

  200199 

Backup Withholding and Information Reporting

  200199 

Reporting Requirements

  200199 

DESCRIPTION OF TGC CAPITAL STOCK

  201200 

Authorized Capital Stock

  201200 

Common Stock

  201200 

Preferred Stock

  201200 

Anti-Takeover Effects of Texas Law, TGC's Amended and Restated Certificate of Formation and Amended and Restated Bylaws

  202201 

Limitation of Director Liability

  203202 

Listing

  203202 

Transfer Agent and Registrar

  203202 

COMPARISON OF SHAREHOLDER RIGHTS

  204203 

EXPERTS

  212211 

Dawson

  212211 

TGC

  212211 

UNAUDITED PRO FORMA CONDENSED COMBINED CONSOLIDATED FINANCIAL INFORMATION

  213212 

LEGAL MATTERS

  224222 

DATES FOR SUBMISSION OF SHAREHOLDER PROPOSALS FOR THE 2014 AND 2015 ANNUAL MEETINGS

  225223 

Dawson

  225223 

TGC

  225223 

HOUSEHOLDING OF JOINT PROXY STATEMENT/PROSPECTUS

  227224 

WHERE YOU CAN FIND MORE INFORMATION

  228225 

INDEX TO FINANCIAL STATEMENTS

  F-1 

LIST OF ANNEXES

  
 
 

Annex A—Agreement and Plan of Merger

    

Annex B—Opinion of Raymond James & Associates, Inc.

    

Annex C—Opinion of Stephens, Inc.

    

Annex D—Form of TGC Shareholder Voting Agreement

    

Annex E—Form of Dawson Shareholder Voting Agreement

    

Annex F—Form of Employment Agreement

    

Annex G—Form of Amendment to Second Restated ArticlesCertificate of IncorporationFormation of Dawson

    

Annex H—Form of Amendment to Amended and Restated Certificate of Formation of TGC

    

Annex I—Form of Indemnification Agreement

    

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QUESTIONS AND ANSWERS ABOUT THE MERGER

        The following are brief answers to common questions that you may have regarding the proposals being considered at the special meeting of Dawson shareholders, which we refer to as the Dawson special meeting, and the special meeting of TGC shareholders, which we refer to as the TGC special meeting. Dawson and TGC urge you to read carefully this entire joint proxy statement/prospectus because the information in this section may not provide all the information that might be important to you in determining how to vote. Additional important information is also contained in the annexes to, and the documents incorporated by reference in, this joint proxy statement/prospectus. See "Where You Can Find More Information" beginning on page 228.225.

        In this joint proxy statement/prospectus, unless the context otherwise requires, "TGC" refers to TGC Industries, Inc., a Texas corporation, and its consolidated subsidiaries, "Merger Sub" refers to Riptide Acquisition Corp., a Texas corporation and wholly owned subsidiary of TGC, "Dawson" refers to Dawson Geophysical Company, a Texas corporation, and its consolidated subsidiaries, the "merger agreement" refers to the Agreement and Plan of Merger, dated October 8, 2014, by and among Dawson, Merger Sub and TGC, as it may be amended from time to time, and the "merger" refers to the merger of Merger Sub with and into Dawson, as contemplated by the merger agreement. A copy of the merger agreement is attached as Annex A to this joint proxy statement/prospectus.

Q:
Why am I receiving this document?

A:
You are receiving this joint proxy statement/prospectus because you are a shareholder of record of either Dawson or TGC as of [                ],December 29, 2014, the record date for the special meetings.

TGC and Dawson have agreed to combine their businesses by means of a merger of Merger Sub with and into Dawson, with Dawson surviving the merger as a wholly owned subsidiary of TGC. Immediately prior to the merger, TGC has agreed to effect a name change to be named "Dawson Geophysical Company" and Dawson has agreed to effect a name change to be named "Dawson Operating Company."

In order to complete the merger, among other conditions, TGC shareholders must vote to approve (i) the share issuance proposal, (ii) the reverse stock split proposal and (iii) the TGC name change proposal. In addition, Dawson shareholders must vote to approve the merger proposal and the Dawson name change proposal. Dawson and TGC will hold separate special meetings to obtain these approvals.

At the Dawson special meeting, Dawson shareholders will also be voting on a non-binding advisory resolution on certain compensation that may be paid or become payable to Dawson's named executive officers upon consummation of the merger. However, approval by Dawson shareholders of such compensation is not a condition to the merger. Accordingly, even if Dawson shareholders do not approve such compensation, if all closing conditions to the merger are satisfied, Dawson and TGC will be obligated to close the merger, and such compensation will be paid or become payable to Dawson's named executive officers.

This joint proxy statement/prospectus, which you should read carefully, contains important information about the merger, the merger agreement and the special meetings of Dawson and TGC shareholders. Dawson and TGC are each delivering this document to their shareholders because it is a proxy statement being used by the board of directors of both Dawson and TGC to solicit proxies of shareholders in connection with their respective special meetings. In addition, this document is a prospectus being delivered to Dawson shareholders because TGC is offering shares of its common stock to Dawson shareholders in exchange for their shares of Dawson common stock in connection with the proposed merger.


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Q:
What will happen in the merger?

A:
In the merger, Merger Sub will be merged with and into Dawson, with Dawson surviving as a direct wholly owned subsidiary of TGC. After the merger, the current shareholders of Dawson and the current shareholders of TGC will be the shareholders of TGC, which will have changed its name to "Dawson Geophysical Company."

Q:
What are holders of Dawson common stock being asked to vote on?

A:
Holders of Dawson common stock are being asked to:

approve the merger agreement (which we refer to as the "merger proposal");

approve an amendment to Dawson's second restated articles of incorporation to effect the change of Dawson's name to "Dawson Operating Company" immediately prior to the merger and make other technical amendments to conform with the requirements of the Texas Business Organizations Code (which we refer to as the "Dawson name change proposal");

approve a non-binding advisory resolution on certain compensation that may be paid or become payable to Dawson's named executive officers upon consummation of the merger (which we refer to as the "advisory resolution proposal"); and

approve adjournments of the Dawson special meeting, if necessary or appropriate, to permit the solicitation of additional proxies if there are insufficient votes at the time of the Dawson special meeting to adopt the foregoing proposals (which we refer to as the "Dawson adjournment proposal").

Q:
What are holders of TGC common stock being asked to vote on?

A:
Holders of TGC common stock are being asked to:

approve the issuance of shares of TGC common stock to Dawson shareholders pursuant to the terms of the merger agreement (which we refer to as the "share issuance proposal");

approve an amendment to TGC's amended and restated certificate of formation to effect a reverse stock split with respect to TGC common stock on a 1-for-3 ratio immediately prior to the merger (which we refer to as the "reverse stock split proposal");

approve an amendment to TGC's amended and restated certificate of formation to effect the change of the name of TGC to "Dawson Geophysical Company" immediately prior to the merger (which we refer to as the "TGC name change proposal"); and

approve adjournments of the TGC special meeting, if necessary or appropriate, to permit the solicitation of additional proxies if there are insufficient votes at the time of the TGC special meeting to approve the foregoing proposals (which we refer to as the "TGC adjournment proposal").

Q:
Why have Dawson and TGC decided to merge?

A:
Dawson and TGC believe that the merger will provide strategic and financial benefits to their shareholders, clients and employees, including:

increased data acquisition crew capacity, with a combined crew count of 21 crews in the continental United States and 7 in Canada, as currently configured, as well as combined channel counts in excess of 323,000 and more than 240 vibrator energy source units as of September 30, 2014;

expanded geographic presence, including every major basin in the United States and strong Canadian presence;

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Q:
Why is my vote important?

A:
Completion of the merger requires the approval of the shareholders of Dawson and TGC at their respective special meetings. If you do not return your proxy card by mail or submit your proxy by telephone or over the Internet or vote in person at the special meetings, it may be difficult for Dawson and TGC to obtain the necessary quorum to hold their special meetings.

In addition, because approval of the merger proposal and the Dawson name change proposal require the affirmative vote of at least two-thirds of the outstanding shares of Dawson common stock, and because approval of the reverse stock split proposal and the TGC name change proposal require the affirmative vote of at least two-thirds of the outstanding shares of TGC, if you are a Dawson Shareholder or a TGC shareholder and you fail to vote or abstain from voting, that will have the same effect as a vote "AGAINST" approval of the merger proposal or related matters.

Dawson's board of directors recommends that Dawson shareholders vote "FOR" the merger proposal, "FOR" the Dawson name change proposal, "FOR" the advisory resolution proposal and "FOR" the Dawson adjournment proposal.

TGC's board of directors recommends that TGC shareholders vote "FOR" the share issuance proposal, "FOR" the reverse stock split proposal, "FOR" the TGC name change proposal and "FOR" the TGC adjournment proposal.


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Q:
How do I exchange my shares of TGC common stock if I am a TGC shareholder?

A:
Registered TGC shareholders may hold some or all of their shares of TGC common stock electronically in book-entry form, in certificate form or in a combination of certificate and book-entry form.

If you hold any of your shares of TGC common stock in certificate form,do not send in any stock certificates at this time. Registered holders of TGC common stock who hold shares of TGC common stock in book-entry form or in certificated form will be sent a letter of transmittal from TGC's transfer agent as soon as practicable after the effective date of the reverse stock split. The letter of transmittal will contain instructions on how to surrender your certificate(s) representing your pre-reverse stock split shares and book-entry shares to the transfer agent. Upon receipt of your properly completed and executed letter of transmittal and any share certificates that you hold, TGC will issue to you the appropriate number of shares of TGC common stock electronically in book-entry form (or in certificate form if you request physical certificates) and provide a statement reflecting the number of shares registered in your account. TGC will not issue any new shares of TGC common stock in book-entry form (or certificated form if you request physical certificates) to you until you surrender your outstanding certificate(s), together with the properly completed and executed letter of transmittal, to the transfer agent.

Upon the implementation of the reverse stock split, TGC intends to treat shares of TGC common stock held by shareholders through a bank, broker, custodian or other nominee in the same manner as registered shareholders whose shares are registered in their names. Banks, brokers, custodians or other nominees will be instructed to effect the reverse stock split for their beneficial holders holding TGC common stock in street name. However, these banks, brokers, custodians or other nominees may have different procedures than registered shareholders for processing the reverse stock split. Shareholders who hold shares of TGC common stock with a bank, broker, custodian or other nominee and who have any questions in this regard are encouraged to contact their banks, brokers, custodians or other nominees.

Q:
What will I receive in the merger in exchange for my shares of Dawson common stock?

A:
Under the merger agreement, Dawson shareholders will receive 1.760 shares of TGC common stock for every one share of Dawson common stock they own, after giving effect to the proposed reverse stock split. For instance, a registered holder of 1,000 shares of Dawson common stock will receive 1,760 shares of TGC common stock on a post-reverse stock split basis. We refer to the number of shares of TGC common stock that Dawson shareholders will receive for each share of Dawson common stock they hold as the "exchange ratio." This ratio has been calculated assuming the effectiveness of a 1-for-3 reverse stock split with respect to TGC common stock immediately prior to the merger.

TGC will not issue any fractional shares of its common stock in connection with the proposed merger. For each fractional share that would otherwise be issued to Dawson shareholders, TGC will pay cash (without interest) in an amount equal to the product of the fractional share and the closing price of shares of TGC common stock on NASDAQ on the business day immediately prior


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Q:
What is the value of the merger consideration that Dawson shareholders are to receive?

A:
The number of shares of TGC common stock to be issued in the merger for each share of Dawson common stock is fixed (except in the event of any stock split, reverse stock split, stock dividend, combination, reclassification, recapitalization or other similar transaction or event with respect to Dawson common stock or TGC common stock (other than the 1-for-3 TGC reverse stock split occurring immediately prior to the merger)) and will not be adjusted for changes in the market price of either Dawson common stock or TGC common stock. Accordingly, any change in the price of TGC common stock prior to the merger will affect the market value of the merger consideration that Dawson shareholders will receive as a result of the merger. For additional information regarding the value of the merger consideration, see "The Merger—The Merger Consideration" on page 122.120.

The closing price of Dawson common stock on NASDAQ on October 8, 2014, the last full trading day prior to the public announcement of the merger, was $17.57. The closing price of Dawson common stock on NASDAQ on November 5,December 29, 2014, the last practicable full trading day prior to the date of this joint proxy statement/prospectus, was $16.64.$12.11.

The closing price of TGC common stock on NASDAQ on October 8, 2014, the last full trading day prior to the public announcement of the merger, was $3.34. The closing price of TGC common stock on NASDAQ on November 5,December 29, 2014, the last practicable full trading day prior to the date of this joint proxy statement/prospectus, was $3.16.$2.26.

You should obtain current stock price quotations for Dawson common stock and TGC common stock before voting. Dawson common stock and TGC common stock are currently listed on NASDAQ under the symbols "DWSN" and "TGE," respectively.

Q:
Will TGC shareholders receive any additional shares as a result of the merger?

A:
No. TGC shareholders will not receive any additional shares of TGC common stock as a result of the merger, except to the extent that the 1-for-3 reverse stock split to be effected in connection with the merger would result in the rounding up of fractional shares.

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Q:
What will happen to shares of TGC common stock in the merger?

A:
Holders of shares of TGC common stock will continue to own their existing shares, which will not be converted or canceled in the merger,merger; however the number of shares they hold will be adjusted downward pursuant to the proposed reverse stock split. In the merger, each outstanding share of Dawson common share will be converted into the right to receive 1.760 shares of TGC common stock after giving effect to the proposed reverse stock split. As of November 5,December 29, 2014, there were 8,065,2338,077,580 shares of Dawson common stock, stock options to acquire up to 91,150 shares of Dawson common stock, 21,97775,575 Dawson restricted stock units, 21,999,15721,997,007 shares of TGC common stock and stock options to acquire up to 956,271839,267 shares of TGC common stock outstanding. Immediately prior to the merger, TGC will effect a 1-for-3 reverse stock split with respect to the TGC common stock, thereby reducing the total number of outstanding shares of TGC common stock to approximately 7.3 million shares. Based on such number of shares and options outstanding and after giving effect to the proposed reverse stock split, there would be an aggregate of approximately 21.6 million outstanding shares of TGC common stock after the completion of the merger, of which approximately 66% and 34% of those outstanding shares would be held by current Dawson shareholders and TGC shareholders, respectively.

Q:
Will the merger affect the board of directors or officers of TGC after the merger?

A:
Yes. Under the merger agreement, TGC has agreed to take all necessary actions to cause, as of the effective time of the merger, the TGC board of directors to include Stephen C. Jumper, Craig Cooper, Gary M. Hoover, Ted North and Mark A. Vander Ploeg, each of whom is currently a director of Dawson. We expect that Wayne A. Whitener, Allen T. McInnes, Ph.D. and William J. Barrett will continue to serve as directors of TGC after the merger and the other current directors of TGC will resign from the TGC board of directors. Accordingly, in order to accommodate the additional directors, at the effective time of the merger, the TGC board of directors will increase in size to 8 directors. See "The Merger Agreement—Governance Matters" on page 133.131. Pursuant to the merger agreement, TGC will take all necessary action to cause each of the 8 directors noted above to be nominated for continuing election to the board of directors for three years following the effective time of the merger, other than Mr. Barrett, who will be nominated for election to the board of directors for one year following the effective time of the merger, and Messrs. Jumper and Whitener, who will be nominated for election as long as they remain an officer of TGC or Dawson following the merger.

Stephen C. Jumper will be appointed as the Chairman, President and Chief Executive Officer of TGC as of the effective time of the merger, and Wayne A. Whitener will become the Vice Chairman.

The following individuals (currently officers of Dawson) will be appointed to serve as officers of TGC (in the capacities set forth below):

Name
 Office
C. Ray Tobias Executive Vice President and
  Chief Operating Officer

Christina W. Hagan

 

Executive Vice President,
  Chief Accounting Officer and Secretary

James W. Thomas

 

Executive Vice President and
  Chief Technology Officer

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        Additionally, the following individuals (currently officers of TGC) will continue serving as officers of TGC (in the capacities set forth below):

Name
 Office
James K. Brata Executive Vice President and
  Chief Financial Officer

Daniel G. Winn

 

Senior Vice President
Q:
Who is entitled to vote at the Dawson special meeting and the TGC special meeting?

A:
Dawson shareholders:    The record date for the Dawson special meeting is [                ].December 29, 2014. Only holders of record of shares of Dawson common stock outstanding and entitled to vote as of the close of business on the record date are entitled to notice of, and to vote at, the Dawson special meeting or any adjournment or postponement of the Dawson special meeting.

TGC shareholders:    The record date for the TGC special meeting is [                ].December 29, 2014. Only holders of record of shares of TGC common stock outstanding and entitled to vote as of the close of business on the record date are entitled to notice of, and to vote at, the TGC special meeting or any adjournment or postponement of the TGC special meeting.

Q:
What vote of Dawson shareholders is required to approve the transaction with TGC and to approve the advisory resolution proposal?

A:
The affirmative vote of at least two-thirds of the outstanding shares of Dawson common stock is required to approve the merger proposal. The affirmative vote of at least two-thirds of the outstanding shares of Dawson common stock is also required to approve the Dawson name change proposal.

The affirmative vote of a majority of shares of Dawson common stock present in person or represented by proxy and entitled to vote at the Dawson special meeting, in which a quorum is present, is required to approve the non-binding advisory resolution on certain compensation that may be paid or become payable to Dawson's named executive officers upon consummation of the merger. However, approval by Dawson shareholders of such compensation is not a condition to the merger. Accordingly, even if Dawson shareholders do not approve such compensation, if all closing conditions to the merger are satisfied, Dawson and TGC will be obligated to close the merger, and such compensation will be paid or become payable to Dawson's named executive officers.

The Dawson adjournment proposal, if necessary or appropriate to solicit additional proxies, requires the affirmative vote of the holders of Dawson common stock representing a majority of the votes present in person or represented by proxy and entitled to vote at the Dawson special meeting, whether or not a quorum exists.

At the close of business on [                        ],December 29, 2014, the record date for the Dawson special meeting, directors and executive officers of Dawson had the right to vote 2.40%2.39% of the outstanding shares of Dawson common stock. Certain of those executive officers and directors, who collectively owned approximately 2.40%2.39% of the shares of Dawson common stock outstanding on such date, have entered into a voting agreement with TGC, which we refer to as the Dawson shareholder voting agreement. Pursuant to and subject to the terms of the Dawson shareholder voting agreement, those directors and executive officers have agreed, among other things, to vote their shares of Dawson common stock in favor of approval of the merger proposal at the Dawson special meeting. For additional information on the Dawson shareholder voting agreement, see "The Dawson Shareholder Voting Agreement" beginning on page 157.155.


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Q:
How does the Dawson board of directors recommend that Dawson shareholders vote with respect to the proposed merger, the proposed Dawson name change and the advisory resolution proposal?

A:
Dawson's board of directors recommends that Dawson shareholders vote "FOR" the merger proposal and "FOR" the Dawson name change proposal. For additional information on the recommendation of Dawson's board of directors, see "The Merger—Dawson's Reasons for the Merger and Recommendation of Dawson's Board of Directors" beginning on page 95.93.

In addition, Dawson's board of directors recommends that Dawson shareholders vote "FOR" the advisory resolution proposal.

You should note that Dawson's directors and executive officers have interests in the merger as directors or officers that are different from, or in addition to, the interests of other Dawson shareholders. For information relating to the interests of Dawson's directors and executive officers in the merger, see "The Merger—Conflicts of Interests" beginning on page 124.122.

Q:
What vote of TGC shareholders is required to approve the transaction with Dawson, the reverse stock split and the change of TGC's name?

A:
The affirmative vote of at least two-thirds of the outstanding shares of TGC common stock is required to approve the reverse stock split proposal and the TGC name change proposal.

The share issuance proposal requires the affirmative vote of a majority of shares of TGC common stock present in person or represented by proxy and entitled to vote and that voted for or against or expressly abstained with respect to the proposal, in which a quorum is present.

The TGC adjournment proposal, if necessary or appropriate to solicit additional proxies, requires the affirmative vote of the holders of TGC common stock representing a majority of the votes present in person or represented by proxy and entitled to vote and that voted for or against or expressly abstained with respect to the proposal, whether or not a quorum exists.

At the close of business on [                ],December 29, 2014, the record date for the TGC special meeting, directors and executive officers of TGC and their respective affiliates had the right to vote 27.59%27.60% of the outstanding shares of TGC common stock. Those executive officers and directors and their affiliates have entered into voting agreements with Dawson, which we refer to as the TGC shareholder voting agreements. Pursuant to and subject to the terms of the TGC shareholder voting agreements, those directors and executive officers and their respective affiliates have agreed, among other things, to vote their shares of TGC common stock in favor of the share issuance proposal, the reverse stock split proposal, the TGC name change proposal and the TGC adjournment proposal. For additional information on the TGC shareholder voting agreements, see "The TGC Shareholder Voting Agreements" beginning on page 155.153.

For additional information on the vote required to approve the merger proposal, see "The TGC Special Meeting" beginning on page 72.70.


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Q:
What is required to consummate the merger?

A:
To consummate the merger, Dawson's shareholders must approve the merger proposal and the Dawson name change proposal and TGC's shareholders must approve the share issuance proposal, the reverse stock split proposal and the TGC name change proposal. The merger, the amendment to Dawson's second amended and restated articles of incorporation to change the name of Dawson to "Dawson Operating Company," the issuance of shares of TGC common stock pursuant to the terms of the merger agreement, the amendment to TGC's amended and restated certificate of formation to effect the reverse stock split and the amendment to TGC's amended and restated certificate of formation to change the name of TGC to "Dawson Geophysical Company" will not take place unless all of these proposals are approved by Dawson's shareholders or TGC's shareholders, as applicable. Therefore, the completion of the merger cannot proceed without the approval of these proposals.

Q:
How does the TGC board of directors recommend that TGC shareholders vote with respect to the share issuance proposal, the reverse stock split proposal and the name change proposal?

A:
TGC's board of directors recommends that TGC shareholders vote "FOR" the share issuance proposal, "FOR" the reverse stock split proposal and "FOR" the TGC name change proposal. For additional information on the recommendation of TGC's board of directors, see "The Merger—TGC's Reasons for the Merger and Recommendation of TGC's Board of Directors" beginning on page 100.98.

You should note that TGC's directors and executive officers have interests in the merger as directors or officers that are different from, or in addition to, the interests of other TGC shareholders. For information relating to the interests of TGC's directors and executive officers in the merger, see "The Merger—Conflicts of Interests" beginning on page 124.122.

Q:
What constitutes a quorum for the special meetings?

A:
With respect to each special meeting, a majority of the outstanding shares of common stock entitled to vote at the close of business on the record date being present in person or represented by proxy constitutes a quorum for the special meeting. While abstentions will be counted for purposes of determining whether a quorum is present, broker non-votes (which are described below) will not.

Q:
When and where are the special meetings?

A:
The Dawson special meeting will take place at the offices of Baker Botts L.L.P. at 2001 Ross Avenue, Suite 1100, Dallas, Texas 75201 at 8:3:00 a.m.p.m., central time, on [                    ], [                    ].Monday, February 9, 2015. For additional information relating to the Dawson special meeting, see "The Dawson Special Meeting" beginning on page 62.60.

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Q:
Is the consummation of the merger subject to any conditions other than the approval of Dawson and TGC shareholders?

A:
Yes. In addition to Dawson and TGC shareholder approvals, the consummation of the merger is contingent upon the satisfaction or, to the extent permitted by law, waiver of the following conditions:

clearance under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, or HSR Act;Act (for which early termination of the waiting period was granted on November 14, 2014);

the absence of any judgment, injunction, order or decree in effect, or any law, statute, rule or regulation enacted, that prohibits the consummation of the merger;

the effectiveness of a registration statement on Form S-4 of which this joint proxy statement/prospectus forms a part and the authorization of the listing of the shares of TGC common stock to be issued in connection with the merger on NASDAQ;

receipt by each party of an opinion from its counsel, in a form and substance reasonably satisfactory to that party, dated as of the closing date of the merger, to the effect that (1) the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended, or the Code, and (2) no gain or loss will be recognized for United States federal income tax purposes by the shareholders of Dawson upon the exchange of shares of Dawson common stock for shares of TGC common stock pursuant to the proposed merger (except with respect to cash received in lieu of fractional shares);

certain officers of TGC and Dawson having entered into employment agreements with TGC as of the effective time of the merger;

receipt by TGC and Dawson of certain third party consents; and

other customary conditions, including the absence of a material adverse effect with respect to either TGC's or Dawson's respective businesses.

        If any of the conditions set forth above fail to occur and such conditions are not waived, the merger will not be consummated and the merger agreement will terminate. Either party may waive any of their respective conditions if the law allows such party to do so. If either party were to waive a condition, the consummation of the merger would occur without the condition having been met. Neither Dawson nor TGC can give any assurance regarding when or if all of the conditions to the merger will be either satisfied or waived or that the merger will occur as intended.

        The proposal relating to the approval of certain compensation to be paid to Dawson's named executive officers upon consummation of the merger is a non-binding advisory resolution and is not a condition to the merger. Accordingly, even if Dawson shareholders do not approve such compensation, if all closing conditions to the merger are satisfied, Dawson and TGC will be obligated to close the merger, and such compensation will be paid or become payable to Dawson's named executive officers.

        For additional information on the conditions to the consummation of the merger, see "The Merger Agreement—Conditions to Completion of the Merger" beginning on page 148.146.

Q:
What do I need to do now?

A:
After reading and considering carefully the information contained in this joint proxy statement/prospectus, please vote promptly by calling the toll-free number listed on your proxy card, accessing the Internet website listed on your proxy card or completing, signing, dating and returning your proxy card in the enclosed postage-paid envelope. If you hold your stock in "street name" through a bank, broker or other nominee, you must direct your bank, broker or other nominee to vote in accordance with the instructions you have received from your bank, broker or

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