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                                                                   EXHIBIT 4.12



                                TRUST AGREEMENT
                                       OF
                                 APACHE TRUST I

         THIS TRUST AGREEMENT OF APACHE TRUST I is dated as of March 13, 2000
(this "Trust Agreement"), by and among Apache Corporation, a Delaware
corporation, as sponsor (the "Sponsor"), and The Chase Manhattan Bank, a New
York banking corporation, as trustee, Chase Manhattan Bank Delaware, a Delaware
banking corporation, as trustee, and Thomas L. Mitchell and Matthew W. Dundrea,
each an individual, as trustees (collectively, the "Trustees"). The Sponsor and
the Trustees hereby agree as follows:

         1. The trust created hereby shall be known as "Apache Trust I" (the
"Trust"), in which name the Trustees or the Sponsor, to the extent provided
herein, may conduct the business of the Trust, make and execute contracts, and
sue and be sued.

         2. The Sponsor hereby assigns, transfers, conveys and sets over to the
Trust the sum of $10. Such amount shall constitute the initial trust estate. It
is the intention of the parties hereto that the Trust created hereby constitute
a business trust under Chapter 38 of Title 12 of the Delaware Code, 12 Del. C.
Section 3801, et seq. (the "Business Trust Act"), and that this document
constitute the governing instrument of the Trust. The Trustees are hereby
authorized and directed to execute and file a certificate of trust with the
Secretary of State of the State of Delaware in such form as the Trustees may
approve.

         3. The Sponsor and the Trustees will enter into an amended and
restated Trust Agreement satisfactory to each such party to provide for the
contemplated operation of the Trust created hereby and the issuance of the
trust preferred securities and trust common securities referred to therein.
Prior to the execution and delivery of such amended and restated Trust
Agreement, the Trustees shall not have any duty or obligation hereunder or
with respect of the trust estate, except as otherwise contemplated by this Trust
Agreement, required by applicable law or as may be necessary to obtain prior to
such execution and delivery any licenses, consents or approvals required by
applicable law or otherwise. Notwithstanding the foregoing, the Trustees may
take all actions deemed proper as are necessary to effect the transactions
contemplated herein.

         4. The Sponsor, on behalf of the Trust, is hereby authorized (i) to
prepare and file with the Securities and Exchange Commission (the "Commission")
and to execute, in the case of the 1933 Act Registration Statement and 1934 Act
Registration Statement (as herein defined), on behalf of the Trust, (a) a
Registration Statement (the "1933 Act Registration Statement"), including all
pre-effective and post-effective amendments thereto, relating to the
registration under the Securities Act of 1933, as amended (the "1933 Act"), of
the trust preferred securities of the Trust, (b) any preliminary prospectus or
prospectus or supplement thereto relating to the trust preferred securities of
the Trust required to be filed pursuant to the 1933 Act, and (c) a Registration
Statement on Form 8-A or other appropriate form (the "1934 Act Registration
Statement"), including all pre-effective and post-effective amendments
thereto, relating to the registration of the trust preferred securities of the
Trust under the Securities Exchange Act of ]934, as amended; (ii) if and at
such time as determined by the Sponsor, to file with the New



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York Stock Exchange or other exchange, or the National Association of
Securities Dealers ("NASD"), and execute on behalf of the Trust a listing
application and all other applications, statements, certificates, agreements
and other instruments as shall be necessary or desirable to cause the trust
preferred securities of the Trust to be listed on the New York Stock Exchange
or such other exchange, or the NASD's Nasdaq National Market; (iii) to file and
execute on behalf of the Trust, such applications, reports, surety bonds,
irrevocable consents, appointments of attorney for service of process and other
papers and documents that shall be necessary or desirable to register the trust
preferred securities of the Trust under the securities or "blue sky" laws of
such jurisdictions as the Sponsor, on behalf of the Trust, may deem necessary
or desirable; (iv) to execute and deliver letters or documents to, or
instruments for filing with, a depository relating to the trust preferred
securities of the Trust; and (v) to execute, deliver and perform on behalf of
the Trust an underwriting agreement with one or more underwriters relating to
the offering of the trust preferred securities of the Trust.

         In the event that any filing referred to in this Section 4 is required
by the rules and regulations of the Commission, the New York Stock Exchange or
other exchange, NASD, or state securities or "blue sky" laws to be executed on
behalf of the Trust by the Trustees, the Trustees, in their capacity as
trustees of the Trust, are hereby authorized to join in any such filing and to
execute on behalf of the Trust any and all of the foregoing, it being
understood that each of the Trustees, in its capacity as a trustee of the
Trust, shall not be required to join in any such filing or execute on behalf of
the Trust any such document unless such Trustee is required to do so by the
rules and regulations of the Commission, the New York Stock Exchange or other
exchange, NASD, or state securities or "blue sky" laws.

         5.     This Trust Agreement may be executed in one or more
counterparts.

         6.     The number of trustees of the Trust initially shall be four and
thereafter the number of trustees of the Trust shall be such number as shall
be fixed from time to time by a written instrument signed by the Sponsor which
may increase or decrease the number of trustees of the Trust; provided,
however, that to the extent required by the Business Trust Act, one trustee of
the Trust shall either be a natural person who is a resident of the State of
Delaware or, if not a natural person, an entity which has its principal place
of business in the State of Delaware and otherwise meets the requirements of
applicable law. Subject to the foregoing, the Sponsor is entitled to appoint or
remove without cause any trustee of the Trust at any time. Any trustee of the
Trust may resign upon thirty days' prior notice to the Sponsor.

         7.     The Sponsor hereby agrees to (i) reimburse the Trustees for all
reasonable expenses (including reasonable fees and expenses of counsel and
other experts) and (ii) indemnify, defend and hold harmless the Trustees and
any of the officers, directors, employees and agents of the Trustees (the
"Indemnified Persons") from and against and all losses, damages, liabilities,
claims, actions, suits, costs, expenses, disbursements (including the
reasonable fees and expenses of counsel), taxes and penalties of any kind and
nature whatsoever (collectively, "Expenses"), to the extent that such Expenses
arise out of or are imposed upon or asserted at any time against such
Indemnified Persons with respect to the performance of this Trust Agreement,
the creation, operation or termination of the Trust or the transactions
contemplated hereby; provided, however, that the Sponsor shall not be required
to indemnify any Indemnified Person for any Expenses



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which are a result of the willful misconduct, bad faith or gross negligence of
such Indemnified Person.

         8.     The Trust may be dissolved and terminated before the issuance
of the trust preferred securities of the Trust at the election of the Sponsor.

         9.     This Trust Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to conflict
of laws principles).



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         IN WITNESS WHEREOF, the parties hereto have caused this Trust
Agreement to be duly executed as of the day and year first above written.

                                          APACHE CORPORATION, as Sponsor

                                          By:     /s/ MATTHEW W. DUNDREA
                                               --------------------------------
                                               Name:  Matthew W. Dundrea
                                               Title: Vice President and
                                                      Treasurer


                                          THE CHASE MANHATTAN BANK, as
                                          trustee

                                          By:     /s/ WALTER I. JOHNSON, III
                                               --------------------------------
                                               Name:  Walter I. Johnson, III
                                               Title: Assistant Treasurer



                                          CHASE MANHATTAN BANK
                                          DELAWARE, as trustee

                                          By:     /s/ DENIS KELLY
                                               --------------------------------
                                               Name:  Denis Kelly
                                               Title: Assistant Vice President


                                          THOMAS L. MITCHELL, as trustee


                                          /s/ THOMAS L. MITCHELL
                                          -------------------------------------


                                          MATTHEW W. DUNDREA, as trustee


                                          /s/ MATTHEW  W. DUNDREA
                                          -------------------------------------





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