EXHIBIT 4.1


                            CERTIFICATE OF AMENDMENT
                                       OF
                         ANADARKO PETROLEUM CORPORATION
                      RESTATED CERTIFICATE OF INCORPORATION


      Anadarko Petroleum Corporation (the "Corporation"), a corporation
organized and existing under and by virtue of the General Corporation Law of the
State of Delaware, does hereby certify that:

            (i) The amendments set forth below to the Corporation's Restated
      Certificate of Incorporation previously filed in the Office of the
      Secretary of State of Delaware on August 29, 1986, as amended, have been
      duly adopted by the Board of Directors of the Corporation, and the Board
      has declared said amendments to be advisable and called a meeting of the
      stockholders of the Corporation for consideration thereof.

            (ii) Thereafter, pursuant to resolution of its Board of Directors,
      a special meeting of the stockholders of said corporation was duly called
      and held, upon notice in accordance with Section 222 of the General
      Corporation Law of the State of Delaware, at which meeting the necessary
      number of shares as required by statute were voted in favor of the
      amendments.

            (iii) The first paragraph of Article Fourth thereof is amended and
      restated to read as follows:

                  "FOURTH. The total number of shares which the Corporation
                  shall have authority to issue is 452,000,000 shares, of which
                  (a) 2,000,000 shares shall be Preferred Stock, issuable in
                  series, of the par value of $1.00 per share and (b)
                  450,000,000 shares shall be Common Stock, of the par value of
                  $0.10 per share."

            (iv)  Article Seventh thereof is amended and restated to read
      as follows:

                  "SEVENTH. The business and affairs of the Corporation shall be
                  managed by or under the direction of a Board of Directors
                  consisting of not less than six nor more than fifteen
                  directors, the exact number of directors to be determined from
                  time to time by resolution adopted by affirmative vote of a
                  majority of the entire Board of Directors. The directors shall
                  be divided into three classes, designated Class I, Class II
                  and Class III. Each class shall consist, as nearly as may be
                  possible, of one-third of the total number of directors
                  constituting the entire Board of Directors. At a special
                  meeting of stockholders held on August 27, 1986, Class I
                  directors were elected for a term ending at the 1987 Annual
                  Meeting of Stockholders, Class II directors were elected for a
                  term ending at the 1988 Annual Meeting of Stockholders and
                  Class III directors were elected for a term ending at the 1989
                  Annual Meeting of Stockholders, in each case effective as of
                  the date of filing of this Restated Certificate of
                  Incorporation with the Secretary of State of the State of
                  Delaware. At

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                  each Annual Meeting of Stockholders beginning in
                  1987, successors to the class of directors whose term expires
                  at that Annual Meeting shall be elected for a three-year term.
                  If the number of directors is changed, any increase or
                  decrease shall be apportioned among the classes so as to
                  maintain the number of directors in each class as nearly equal
                  as possible, and any additional director of any class elected
                  to fill a vacancy resulting from an increase in such class
                  shall hold office for a term that shall coincide with the
                  remaining term of that class, but in no case will a decrease
                  in the number of directors shorten the term of any incumbent
                  director. A director shall hold office until the Annual
                  Meeting for the year in which his term expires and until his
                  successor shall be elected and shall qualify, subject,
                  however, to prior death, resignation, retirement,
                  disqualification or removal from office. Any vacancy on the
                  Board of Directors that results from an increase in the number
                  of directors may be filled by a majority of the Board of
                  Directors then in office, provided that a quorum is present,
                  and any other vacancy occurring on the Board of Directors may
                  be filled by a majority of the directors then in office, even
                  if less than a quorum, or by a sole remaining director. Any
                  director elected to fill a vacancy not resulting from an
                  increase in the number of directors shall have the same
                  remaining term as that of his predecessor.

                  Subject to the rights of the holders of any series of
                  Preferred Stock then outstanding, any director, or the entire
                  Board of Directors, may be removed from office at any time,
                  but only for cause."

            (v) These amendments were duly adopted in accordance with the
      provisions of Section 242 of the General Corporation Law of the State of
      Delaware.


      IN WITNESS WHEREOF, Anadarko Petroleum Corporation has caused this
certificate to be signed by J. Stephen Martin, its authorized officer, this 13th
day of July, 2000.


                                          Anadarko Petroleum Corporation


                                          /s/ J. Stephen Martin
                                          ---------------------------
                                          Name: J. Stephen Martin
                                          Title: Vice President