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                                                                     EXHIBIT 4.1


                         ANADARKO PETROLEUM CORPORATION

                              OFFICERS' CERTIFICATE

                  We, Albert L. Richey and Suzanne Suter, Vice President and
Treasurer, and Vice President and Corporate Secretary, respectively, of Anadarko
Petroleum Corporation, a Delaware corporation (the "Company"), hereby certify,
pursuant to Sections 102, 201 and 301 of the Indenture, dated as of March 9,
2001 (the "Indenture"), between the Company and The Bank of New York, as Trustee
(the "Trustee"), that the authorized officer has determined, pursuant to the
authority granted to him by the Executive Committee of the Board of Directors of
the Company at its meeting held on May 1, 2003, that the terms of a series of
Securities to be issued under the Indenture, and the form thereof, are as
follows:

Designation of Securities           3.25% Notes due 2008 (the "Notes").

Aggregate Principal Amount          $350,000,000, except for Notes authenticated
                                    and delivered upon registration of transfer
                                    of, or in exchange for, or in lieu of, other
                                    Notes pursuant to Sections 304, 305, 306,
                                    906 or 1107 of the Indenture and except for
                                    any Notes which pursuant to Section 303 are
                                    deemed never to have been authenticated and
                                    delivered. The Company may reopen this
                                    series of Notes for additional issuances
                                    from time to time pursuant to the terms of
                                    the Indenture.

Denominations                       $1,000 and any integral multiple thereof.

Stated Maturity Date                May 1, 2008.

Interest Rate                       3.25% per annum from May 6, 2003.

Interest Payment Dates              Interest payable semiannually on November 1
                                    and May 1, commencing November 1, 2003.

Regular Record Dates                October 15 or April 15 next preceding an
                                    Interest Payment Date.

Optional Redemption                 The Notes are not redeemable prior to the
                                    Stated Maturity Date.

Place of Payment                    The principal of and interest on the Notes
                                    shall be payable, Notes may be surrendered
                                    for registration of transfer, Notes may be
                                    surrendered for exchange, and notices and
                                    demands to or upon the Company in respect of
                                    the Notes and the Indenture may be served,
                                    at the places designated therefore in the
                                    Indenture.

Other Terms                         The provisions of Article Twelve of the
                                    Indenture shall not apply to the Notes.


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Global Securities                   The Notes shall be issued as a Global
                                    Security. The Depository Trust Company shall
                                    be the Depository.

Settlement                          Payments in respect of principal of and
                                    interest on the Notes shall be made by the
                                    Company in immediately available funds.

Form of Notes                       Attached as Annex A, and incorporated herein
                                    by reference.

We further certify that:

         1. We have read Sections 102, 202, 203 and 301 of the Indenture and the
definitions in the Indenture relating thereto.

         2. The statements made herein are based either upon our personal
knowledge or on information, data and reports furnished to us by the officers,
counsel or employees of the Company who have knowledge of the relevant facts.

         3. In our opinion, we have made such examination or investigation as is
necessary to enable us to express an informed opinion as to whether or not all
conditions provided for in the Indenture with respect to the determination of
the terms of the Notes and the form thereof, and the authentication and delivery
of the Notes, have been complied with.

         4. In our opinion, all conditions precedent to the determination of the
terms and form of the Notes and to the authentication by the Trustee of
$350,000,000 principal amount thereof have been complied with and such Notes may
be delivered in accordance with the Indenture.

         Capitalized terms not otherwise defined herein have the meaning
provided in the Indenture.


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                  IN WITNESS WHEREOF, we have hereunto signed our names this 6th
day of May, 2003.


                                 /s/ Albert L. Richey
                                ---------------------
                                     Albert L. Richey
                                     Vice President and Treasurer


                                 /s/ Suzanne Suter
                                ---------------------
                                     Suzanne Suter
                                     Vice President and Corporate Secretary


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