1 --------------------------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 --------------------------- SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 9) DAWSON GEOPHYSICAL COMPANY (Name of Issuer) --------------------------- COMMON STOCK, $.33 1/3 PAR VALUE (Title of Class of Securities) --------------------------- 239359 10 2 (CUSIP Number) MR. RICHARD E. BLOHM, JR. 1415 LOUISIANA STREET HOUSTON, TEXAS 77002 (713) 739-6500 (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) with a copy to: MR. JOHN R. BRANTLEY BRACEWELL & PATTERSON, L.L.P. 711 LOUISIANA STREET, SUITE 2900 HOUSTON, TEXAS 77002 713-223-2900 --------------------------- NOVEMBER 13, 2000 (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report this acquisition that is the subject of this Schedule 13D, and is filing this Schedule because of Rule 13d-1(e), Rule 13d-1(f) or Rule 13d-1(g), check the following box: [ ] The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act. --------------------------- Page 1 of 7 Pages

2 AMENDMENT NO. 9 TO SCHEDULE 13D CUSIP NO. 239359 10 2 PAGE 2 OF 7 PAGES - -------------------------------------------------------------------------------- 1 Name of Reporting Person; S.S. or IRS Identification Number Pebbleton Corporation N.V. - -------------------------------------------------------------------------------- 2 Check the Appropriate Box If A Member of a Group (a) [ ] (b) [X] - -------------------------------------------------------------------------------- 3 SEC Use Only - -------------------------------------------------------------------------------- 4 Source of Funds WC - -------------------------------------------------------------------------------- 5 Check Box If Disclosure of Legal Proceedings Is Required Pursuant to Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization Netherlands Antilles - -------------------------------------------------------------------------------- 7 Sole Voting Power 0 - -------------------------------------------------------------------------------- 8 Shared Voting Power 1,036,000 - -------------------------------------------------------------------------------- 9 Sole Dispositive Power 0 - -------------------------------------------------------------------------------- 10 Shared Dispositive Power 1,036,000 - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned by Each Reporting Person 1,036,000 - -------------------------------------------------------------------------------- 12 Check Box If The Aggregate Amount In Row (11) Excludes Certain Shares [X] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 19.1% - -------------------------------------------------------------------------------- 14 Type of Reporting Person CO - --------------------------------------------------------------------------------

3 AMENDMENT NO. 9 TO SCHEDULE 13D CUSIP NO. 239359 10 2 PAGE 3 OF 7 PAGES - -------------------------------------------------------------------------------- 1 Name of Reporting Person; S.S. or IRS Identification Number Issam M. Fares - -------------------------------------------------------------------------------- 2 Check the Appropriate Box If A Member of a Group (a) [ ] (b) [X] - -------------------------------------------------------------------------------- 3 SEC Use Only - -------------------------------------------------------------------------------- 4 Source of Funds AF - -------------------------------------------------------------------------------- 5 Check Box If Disclosure of Legal Proceedings Is Required Pursuant to Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization Lebanese - -------------------------------------------------------------------------------- 7 Sole Voting Power 0 - -------------------------------------------------------------------------------- 8 Shared Voting Power 1,036,000 - -------------------------------------------------------------------------------- 9 Sole Dispositive Power 0 - -------------------------------------------------------------------------------- 10 Shared Dispositive Power 1,036,000 - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned by Each Reporting Person 1,036,000 - -------------------------------------------------------------------------------- 12 Check Box If The Aggregate Amount In Row (11) Excludes Certain Shares [X] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 19.1% - -------------------------------------------------------------------------------- 14 Type of Reporting Person IN - --------------------------------------------------------------------------------

4 Page 4 of 7 Pages SCHEDULE 13D AMENDMENT NO. 9 Unless otherwise defined or indicated in this Amendment No. 9, capitalized terms which are used herein and are defined in the Schedule 13D filed October 16, 1998, as heretofore amended ("Original 13D"), shall have the meanings assigned to them in the Original 13D. All information herein with respect to Dawson Geophysical Company, a Texas corporation, is to the best knowledge and belief of the Reporting Persons, as defined herein. ITEM 5. INTEREST IN SECURITIES OF THE ISSUER. (a) As set forth herein, Pebbleton owns 1,036,000 shares of Common Stock of the Issuer, which represents approximately 19.1% of the Common Stock outstanding as of June 30, 2000, as reported by the Issuer in its Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission ("Commission") on August 4, 2000. (b) Mr. Fares may be deemed to beneficially own and thereby share voting and dispositive power over the shares of Common Stock described herein which are held by Pebbleton. See Item 2 of the Original 13D. (c) Set forth in Exhibit A to this Amendment No. 9 is a list of all transactions effected in the Issuer's Common Stock by Pebbleton within the past sixty days, including (i) the identity of the person effecting transactions in the Issuer's Common Stock; (ii) the date of the transaction; (iii) the amount of securities involved; (iv) the price per share of Common Stock; and (v) where and how the transaction was effected. Other than the transactions described in this Item 5, none of the Reporting Persons nor to the knowledge of the Reporting Persons, any of their officers or directors, has effected any transactions in the Common Stock during the preceding sixty days. ITEM 7. MATERIAL TO BE FILED AS EXHIBITS. Exhibit A Transactions in the Common Stock by Pebbleton

5 Page 5 of 7 Pages SIGNATURES After reasonable inquiry and to the best of the undersigned's knowledge and belief, each of the undersigned hereby certifies that the information set forth in this statement is true, complete and correct. Dated: November 15, 2000 PEBBLETON CORPORATION N.V. By: Issam M. Fares, Managing Director By: /s/ Richard E. Blohm, Jr. ---------------------------------- Richard E. Blohm, Jr. Attorney in Fact Dated: November 15, 2000 Issam M. Fares By: /s/ Richard E. Blohm, Jr. ---------------------------------- Richard E. Blohm, Jr. Attorney in Fact

6 Page 6 of 7 Pages INDEX TO EXHIBITS Exhibit A Transactions in the Common Stock by Pebbleton

1 Page 7 of 7 Pages EXHIBIT A TRANSACTIONS IN THE COMMON STOCK BY PEBBLETON With respect to the transactions set forth below, all purchases were made by Pebbleton Corporation N.V. and were effected on The Nasdaq Stock Market, Inc., the exchange on which the shares of Common Stock of Dawson Geophysical Company are traded during the 60 days prior to the filing of this Amendment No. 9. DATE OF NUMBER OF SHARES PRICE PER SHARE PURCHASE PURCHASED ($) 11/07/00 15,000 9.12500 11/08/00 5,000 9.50000 11/09/00 17,000 9.50000 11/13/00 5,000 9.46875 11/13/00 10,000 9.50000 A-1