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

                                 SCHEDULE 13G/A

                    Under the Securities Exchange Act of 1934
                                (Amendment No.4)*

                           DAWSON GEOPHYSICAL COMPANY
        -----------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
        -----------------------------------------------------------------
                         (Title of Class of Securities)

                                    239359102
                              --------------------
                                 (CUSIP Number)

                                December 31, 2002
        ----------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which  this Schedule
is filed:

         / X /    Rule 13d-1(b)
         /   /    Rule 13d-1(c)
         /   /    Rule 13d-1(d)

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in 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 the section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).




                                 SCHEDULE 13G/A
                               CUSIP NO. 239359102


1.       Names of Reporting Persons.
         I.R.S. Identification Nos. of above persons (entities only).

         Quaker Capital Management Corporation
         ------------------------------------------------------------

2.       Check the Appropriate Box if a Member of a Group
         (a)
                  -----
         (b)        X
                  -----

3.       SEC Use Only
                      ---------------------------------------------

4.       Citizenship or Place of Organization                 Pennsylvania
                                                              ---------------

 Number of         5.     Sole Voting Power                   0
 Shares                                                       ---------------
 Beneficially      6.     Shared Voting Power                 513,273
 Owned by                                                     ---------------
 Each Reporting    7.     Sole Dispositive Power              0
 Person With:                                                 ---------------
                   8.     Shared Dispositive Power            513,273
                                                              ---------------

9.       Aggregate Amount Beneficially Owned by Each Reporting Person

         513,273
         ---------

10.      Check if the Aggregate Amount in Row (9) Excludes Certain
         Shares
                  --------

         The Reporting Person disclaims beneficial ownership of 513,273 shares
         owned by its clients.

11.      Percent of Class Represented by Amount in Row (9)    9.39%
                                                              --------

12.      Type of Reporting Person                                  IA
                                                              --------------





                               Page 2 of 6 Pages

                                 SCHEDULE 13G/A
                               CUSIP NO. 239359102


Item 1.

         (a)      Name of Issuer

                  Dawson Geophysical Company
                  -------------------------------------------------------

         (b)      Address of Issuer's Principal Executive Offices

                  508 West Wall, Suite 800, Midland, Texas 79701
                  -------------------------------------------------------
Item 2.

         (a)      Name of Persons Filing

                  Quaker Capital Management Corporation
                  -------------------------------------------------------

         (b)      Address of Principal Business Office or, if none,
                  Residence

                  401 Wood Street, Suite 1300, Pittsburgh, PA  15222
                  -------------------------------------------------------

         (c)      Citizenship

                  Pennsylvania, USA
                  -------------------------------------------------------

         (d)      Title of Class of Securities

                  Common Stock
                  -------------------------------------------------------

         (e)      CUSIP Number

                  239359102
                  -------------------------------------------------------



                               Page 3 of 6 Pages

                                 SCHEDULE 13G/A
                               CUSIP NO. 239359102



Item 3.  If this statement is  filed  pursuant to ss.ss.240.13d-1(b) or 240.13d-
         2(b) or (c), check whether the person filing is a:

     (a)    / /  Broker of dealer registered under section 15 of the Act;

     (b)    / /  Bank as defined in section 3(a)(6) of the Act;

     (c)    / /  Insurance company as defined in section 3(a)(19) of the Act;

     (d)    / /  Investment company registered under section 8 of the Investment
                 Company Act of 1940;

     (e)    /X/  An investment  adviser  in  accordance  with ss.240.13d-1(b)(l)
                 (ii)(E);

     (f)    / /  An employee  benefit  plan or endowment fund in accordance with
                 ss.240.13d-1(b)(1)(ii)(F);

     (g)    / /  A  parent  holding company or control person in accordance with
                 ss.240.13d-1(b)(1)(ii)(G);

     (h)    / /  A savings association as defined in Section 3(b) of the Federal
                 Deposit Insurance Act;

     (i)    / /  A  church  plan  that  is  excluded  from  the definition of an
                 investment  company  under  section 3(c)(14) of  the Investment
                 Company Act of 1940;

     (j)    / /  Group, in accordance with ss.240.13d-1((b)(l)(ii)(J)

Item 4.   Ownership
          ---------

     (a)  The Reporting  Person, in its capacity as investment  adviser,  may be
          deemed to be the  beneficial  owner of  513,273  shares of the  Common
          Stock of the  Issuer  which are owned by various  investment  advisory
          clients of the  Reporting  Person in accounts over which the Reporting
          Person has  discretionary  authority.  The filing of this report shall
          not be  construed as an admission  that the  Reporting  Person is, for
          purposes of Section 13(d) or 13(g) of the Act, the beneficial owner of
          these securities.

     (b)  The shares covered by this report  represent 9.39% of the Common Stock
          of the Issuer.


                               Page 4 of 6 Pages

                                 SCHEDULE 13G/A
                               CUSIP NO. 239359102


     (c)  The  Reporting  Person has shared  voting and  dispositive  power over
          513,273 shares owned by its clients and held in accounts over which it
          has discretionary  authority.  The Reporting Person does not have sole
          voting or  dispositive  power  over any of the  shares  that it may be
          deemed to beneficially own.

Item 5.   Ownership of Five Percent or Less of a Class

          If this  statement  is being  filed to report  the fact that as of the
date hereof,  the reporting person has ceased to be the beneficial owner of more
than five percent of the class of securities, check the following:
                                                                   ----------

Item 6.   Ownership of More than Five Percent on Behalf of Another Person

          The shares  with  respect to which this report is filed are owned by a
variety of investment  advisory clients of the Reporting  Person,  which clients
are  entitled to receive  dividends  on and the  proceeds  from the sale of such
shares. No client is known to own more than 5% of the class.

Item 7.   Identification and Classification of the Subsidiary Which Acquired the
          Security Being Reported on by the Parent Holding Company

          Not applicable.

Item 8.   Identification and Classification of Members of the Group

          Not applicable.

Item 9.   Notice of Dissolution of Group

          Not applicable.

Item 10.  Certification

          By  signing  below I certify  that,  to the best of my  knowledge  and
belief,  the  securities  referred  to above were  acquired  and are held in the
ordinary  course  of  business  and were not  acquired  and are not held for the
purpose of or with the effect of  changing  or  influencing  the  control of the
issuer of the  securities  and were not acquired and are not held in  connection
with or as a participant in any transaction having that purpose or effect.


                               Page 5 of 6 Pages

                                 SCHEDULE 13G/A
                               CUSIP NO. 239359102



                                    SIGNATURE

          After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.


                                     QUAKER CAPITAL MANAGEMENT CORPORATION


                                         February 13, 2003
                                         -------------------------------
                                                 Date


                                         /s/  Mark G. Schoeppner
                                         -------------------------------
                                                 Signature


                                         Mark G. Schoeppner, President
                                         -------------------------------
                                                 Name/Title













                               Page 6 of 6 Pages