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

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                               (Amendment No. 1)*

                              Atwood Oceanics, Inc.
             -------------------------------------------------------
                                (Name of Issuer)

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

                                    050095108
             -------------------------------------------------------
                                 (CUSIP Number)

                                December 31, 2004
             -------------------------------------------------------
             (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 that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).



CUSIP No. 050095108                    13G                    Page 2 of 12 Pages

--------------------------------------------------------------------------------
1       NAME OF REPORTING PERSON /
        I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

                Artisan Partners Limited Partnership
--------------------------------------------------------------------------------
2.      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
        (see Instructions)                                               (a) [ ]

                Not Applicable                                           (b) [ ]
--------------------------------------------------------------------------------
3       SEC USE ONLY

--------------------------------------------------------------------------------
4       CITIZENSHIP OR PLACE OF ORGANIZATION

                Delaware
--------------------------------------------------------------------------------
                        5       SOLE VOTING POWER
     NUMBER OF
                                        None
       SHARES           --------------------------------------------------------
                        6       SHARED VOTING POWER
    BENEFICIALLY
                                        233,000
      OWNED BY          --------------------------------------------------------
                        7       SOLE DISPOSITIVE POWER
        EACH
                                        None
     REPORTING          --------------------------------------------------------
                        8       SHARED DISPOSITIVE POWER
    PERSON WITH
                                        233,000
--------------------------------------------------------------------------------
9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

                233,000
--------------------------------------------------------------------------------
10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
        (see Instructions)

                Not Applicable
--------------------------------------------------------------------------------
11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

                1.5%
--------------------------------------------------------------------------------
12      TYPE OF REPORTING PERSON
        (see Instructions)

                IA
--------------------------------------------------------------------------------

                                  Page 2 of 12



CUSIP No. 050095108                    13G                    Page 3 of 12 Pages

--------------------------------------------------------------------------------
1       NAME OF REPORTING PERSON
        S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

                Artisan Investment Corporation
--------------------------------------------------------------------------------
2.      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
        (see Instructions)                                               (a) [ ]

                Not Applicable                                           (b) [ ]
--------------------------------------------------------------------------------
3       SEC USE ONLY

--------------------------------------------------------------------------------
4       CITIZENSHIP OR PLACE OF ORGANIZATION

                Wisconsin
--------------------------------------------------------------------------------
                        5       SOLE VOTING POWER
     NUMBER OF
                                        None
       SHARES           --------------------------------------------------------
                        6       SHARED VOTING POWER
    BENEFICIALLY
                                        233,000
      OWNED BY          --------------------------------------------------------
                        7       SOLE DISPOSITIVE POWER
        EACH
                                        None
     REPORTING          --------------------------------------------------------
                        8       SHARED DISPOSITIVE POWER
    PERSON WITH
                                        233,000
--------------------------------------------------------------------------------
9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

                233,000
--------------------------------------------------------------------------------
10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
        (see Instructions)

                Not Applicable
--------------------------------------------------------------------------------
11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

                1.5%
--------------------------------------------------------------------------------
12      TYPE OF REPORTING PERSON
        (see Instructions)

                CO
--------------------------------------------------------------------------------

                                  Page 3 of 12



CUSIP No. 050095108                    13G                    Page 4 of 12 Pages

--------------------------------------------------------------------------------
1       NAME OF REPORTING PERSON
        S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

                Andrew A. Ziegler
--------------------------------------------------------------------------------
2.      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
        (see Instructions)                                               (a) [ ]

                Not Applicable                                           (b) [ ]
--------------------------------------------------------------------------------
3       SEC USE ONLY

--------------------------------------------------------------------------------
4       CITIZENSHIP OR PLACE OF ORGANIZATION

                U.S.A.
--------------------------------------------------------------------------------
                        5       SOLE VOTING POWER
     NUMBER OF
                                        None
       SHARES           --------------------------------------------------------
                        6       SHARED VOTING POWER
    BENEFICIALLY
                                        233,000
      OWNED BY          --------------------------------------------------------
                        7       SOLE DISPOSITIVE POWER
        EACH
                                        None
     REPORTING          --------------------------------------------------------
                        8       SHARED DISPOSITIVE POWER
    PERSON WITH
                                        233,000
--------------------------------------------------------------------------------
9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

                233,000
--------------------------------------------------------------------------------
10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
        (see Instructions)

                Not Applicable
--------------------------------------------------------------------------------
11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

                1.5%
--------------------------------------------------------------------------------
12      TYPE OF REPORTING PERSON
        (see Instructions)

                IN
--------------------------------------------------------------------------------

                                  Page 4 of 12



CUSIP No. 050095108                    13G                    Page 5 of 12 Pages

--------------------------------------------------------------------------------
1       NAME OF REPORTING PERSON
        S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

                Carlene Murphy Ziegler
--------------------------------------------------------------------------------
2.      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
        (see Instructions)                                               (a) [ ]

                Not Applicable                                           (b) [ ]
--------------------------------------------------------------------------------
3       SEC USE ONLY

--------------------------------------------------------------------------------
4       CITIZENSHIP OR PLACE OF ORGANIZATION

                U.S.A.
--------------------------------------------------------------------------------
                        5       SOLE VOTING POWER
     NUMBER OF
                                        None
       SHARES           --------------------------------------------------------
                        6       SHARED VOTING POWER
    BENEFICIALLY
                                        233,000
      OWNED BY          --------------------------------------------------------
                        7       SOLE DISPOSITIVE POWER
        EACH
                                        None
     REPORTING          --------------------------------------------------------
                        8       SHARED DISPOSITIVE POWER
    PERSON WITH
                                        233,000
--------------------------------------------------------------------------------
9       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

                233,000
--------------------------------------------------------------------------------
10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
        (see Instructions)

                Not Applicable
--------------------------------------------------------------------------------
11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

                1.5%
--------------------------------------------------------------------------------
12      TYPE OF REPORTING PERSON
        (see Instructions)

                IN
--------------------------------------------------------------------------------

                                  Page 5 of 12



Item 1(a)       Name of Issuer:

                        Atwood Oceanics, Inc.

Item 1(b)       Address of Issuer's Principal Executive Offices:

                        15835 Park Ten Place Drive
                        Houston, Texas 77084

Item 2(a)       Name of Person Filing:

                        Artisan Partners Limited Partnership ("Artisan
                        Partners")
                        Artisan Investment Corporation, the general partner of
                        Artisan Partners ("Artisan Corp.")
                        Andrew A. Ziegler
                        Carlene Murphy Ziegler

Item 2(b)       Address of Principal Business Office:

                        Artisan Partners, Artisan Corp., Mr. Ziegler and Ms.
                        Ziegler are all located at:

                        875 East Wisconsin Avenue, Suite 800 Milwaukee, WI 53202

Item 2(c)       Citizenship:

                        Artisan Partners is a Delaware limited partnership
                        Artisan Corp. is a Wisconsin corporation
                        Mr. Ziegler and Ms. Ziegler are U.S. citizens

Item 2(d)       Title of Class of Securities:

                        Common Stock

Item 2(e)       CUSIP Number:

                        050095108

Item 3          Type of Person:

                        (e) Artisan Partners is an investment adviser registered
                        under section 203 of the Investment Advisers Act of
                        1940; Artisan Corp. is the General Partner of Artisan
                        Partners; Mr. Ziegler and Ms. Ziegler are the principal
                        stockholders of Artisan Corp.

                                  Page 6 of 12



Item 4          Ownership (at December 31, 2004):

                        (a)     Amount owned "beneficially" within the meaning
                                of rule 13d-3:

                                233,000

                        (b)     Percent of class:

                                1.5% (based on 15,098,626 shares outstanding as
                                of December 10, 2004)

                        (c)     Number of shares as to which such person has:

                                (i)     sole power to vote or to direct the
                                        vote: None
                                (ii)    shared power to vote or to direct the
                                        vote: 233,000
                                (iii)   sole power to dispose or to direct the
                                        disposition of: None
                                (iv)    shared power to dispose or to direct
                                        disposition of: 233,000

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 [X].

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

                        Not Applicable

Item 7          Identification and Classification of the Subsidiary Which
                Acquired the Security Being Reported on by the Parent Holding
                Company or Control Person:

                        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 7 of 12



                                    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.

Date:  January 26, 2005

                                ARTISAN INVESTMENT CORPORATION
                                for itself and as general partner of
                                ARTISAN PARTNERS LIMITED PARTNERSHIP

                                By: Lawrence A. Totsky*
                                    --------------------------------------------

                                ANDREW A. ZIEGLER

                                Andrew A. Ziegler*
                                ------------------------------------------------

                                CARLENE MURPHY ZIEGLER

                                Carlene Murphy Ziegler*
                                ------------------------------------------------


                               *By: /s/ Lawrence A. Totsky
                                    --------------------------------------------
                                    Lawrence A. Totsky
                                    Chief Financial Officer of Artisan
                                    Investment Corporation
                                    Attorney-in-Fact for Andrew A. Ziegler
                                    Attorney-in-Fact for Carlene Murphy Ziegler

                                  Page 8 of 12



                                  Exhibit Index

Exhibit 1       Joint Filing Agreement dated as of January 26, 2005 by and among
                Artisan Partners Limited Partnership, Artisan Investment
                Corporation, Andrew A. Ziegler, and Carlene Murphy Ziegler

Exhibit 2       Power of Attorney of Andrew A. Ziegler dated as of April 2, 2002

Exhibit 3       Power of Attorney of Carlene M. Ziegler dated as of April 2,
                2002

                                  Page 9 of 12