Apache Corporation 401(k) Savings Plan Amendment, April 2014

Exhibit 10.1

Apache Corporation 401(k) Savings Plan

Amendment, April 2014

Apache Corporation (“Apache”) sponsors the Apache Corporation 401(k) Savings Plan (the “Plan”). Pursuant to section 10.4 of the Plan, Apache hereby exercises its right to amend the Plan by replacing Appendices A through E with the Appendices A through D attached to this document, effective as of May 16, 2014.

EXECUTED this 20th day of May 2014.

APPENDIX A

Participating Companies

The following Affiliated Entities were actively participating in the Plan as of the following dates:

— END OF APPENDIX A —

APPENDIX B

Corporate Transactions

Over the years, Apache and its Affiliated Entities have engaged in certain acquisitions and disposition transactions. This Appendix contains provisions that apply to employees (including former employees) affected by certain transactions.

Sales

For an Employee who transferred to Natural Gas Clearinghouse (“NGC”) pursuant to the terms of the Employee Benefits Agreement effective April 1, 1990 between Apache and NGC, a Period of Service shall be calculated by treating as employment with Apache any period(s) of employment after April 1, 1990 with NGC or any business that is then treated as a single employer with NGC pursuant to Code §414(b), §414(c), §414(m), or §414(o).

Employees terminated in connection with the summer 1995 sale of certain properties to Citation 1994 Investment Limited Partnership are fully vested in their Plan Accounts as of September 1, 1995.

An Employee who transferred to Producers Energy Marketing LLC (“ProEnergy”) in the first half of 1996 is fully vested in his Plan Accounts as of the date of transfer. If such an individual becomes an Employee again, all new contributions to his Plan Accounts shall vest according to the regular rules.

The following three paragraphs apply to any Employee who transfers to Fieldwood Energy, LLC (“Fieldwood”) or to any business while it is treated as a single employer with Fieldwood pursuant to Code §414(b), §414(c), §414(m), or §414(o) (collectively, the “Fieldwood Group”), and whose transfer occurs pursuant to the closing of the transaction described in the “Purchase and Sale Agreement by and among Apache Corporation, Apache Shelf, Inc., and Apache Deepwater LLC, and Fieldwood Energy, LLC and GOM Shelf LLC” (the “PSA”) that was entered into on July 18, 2013 (a “Transferred Employee”).

Vesting. Notwithstanding subsection 5.3(a), for vesting purposes, a Period of Service for a Transferred Employee shall include his service with the Fieldwood Group after the closing of the transaction until his termination of employment with the Fieldwood Group. Notwithstanding subsection 5.4(b), the earliest date a forfeiture may occur is the date of the Employee’s termination of employment with the Fieldwood Group.

Distributions. A Transferred Employee may take a distribution of the entire distributable amount at any time after his Termination from Service Date from the Company. The distributable amount, as determined under section 6.3, only includes vested benefits. If the Transferred Employee takes a distribution and his vested percentage later increases, he may take additional distribution(s), each of which shall be equal to the entire distributable amount at the time of the distribution. Notwithstanding subsection 6.6(c), the Plan will not cash out a small Account until the Transferred Employee becomes fully vested or, if earlier, he terminates employment with the Fieldwood Group.

Loans. A Transferred Employee may roll over any outstanding loan from the Plan to a qualified plan sponsored by any member of the Fieldwood Group that agrees to accept such a rollover, as long as the rollover is initiated by the last day of the calendar quarter following the calendar quarter in which occurs the Transferred Employee’s Effective Date (as defined in Exhibit F of the PSA). Any loan not rolled over by such date shall be subject to the usual default rules in section 7.6. Notwithstanding Article VI, a Transferred Employee may roll over a loan under this paragraph without taking any other distribution from the Plan.

Acquisitions

A Period of Service for vesting purposes for a New Employee (listed below) shall be determined by treating all periods of employment with the Former Employer Controlled Group as periods of employment with Apache. The “Former Employer Controlled Group” means the Former Employer (listed below), its predecessor company/ies, and any business while such business was treated as a single employer with the Former Employer or predecessor company pursuant to Code §414(b), §414(c), §414(m), or §414(o).

The following individuals are “New Employees” and the following companies are “Former Employers”:

—END OF APPENDIX B—

APPENDIX C

Mariner Energy, Inc.

Introduction

Through a merger effective as of November 10, 2010 (the “Closing Date”), Apache acquired Mariner Energy, Inc., (“Mariner”) which sponsored the Mariner Energy, Inc. Employee Capital Accumulation Plan (“Mariner’s 401(k) Plan”). Mariner’s 401(k) Plan is merged into this Plan as of November 16, 2010. This Appendix describes the special rules that apply to amounts transferred from Mariner’s 401(k) Plan to this Plan, and also describes how the match is calculated for 2010 in this Plan.

Capitalized terms in this Appendix have the same meanings as those given to them in the Plan. The regular terms of the Plan shall apply, except as provided below.

Match

The Company Matching Contribution for 2010 shall be determined pursuant to section 3.2 of the Plan, based on the Participant Contributions and Compensation paid to a Covered Employee after the date of the merger, except as provided in the next sentence. If a Covered Employee’s Participant Contributions to this Plan and his contributions to Mariner’s 401(k) Plan that are subject to the limits of Code §402(g) are $16,500 or (because of catch-up contributions) more during 2010, his Company Matching Contribution for 2010 will be the greater of (a) the aggregate matching contributions he would have received in both this Plan and Mariner’s 401(k) Plan had equal salary deferrals of $16,500 in the aggregate been withheld from each regular paycheck during 2010, minus the match allocated to him for 2010 in Mariner’s 401(k) Plan, or (b) the amount described in the preceding sentence.

The Company Matching Contribution shall vest pursuant to the usual rules in Article V. See Appendix B for additional (pre-Apache) service that is taken into account for vesting purposes.

Incoming Assets

A participant in Mariner’s 401(k) Plan may have as many as seven different types of accounts in that plan. The following distribution rules apply to those incoming accounts (the “Old Mariner Accounts”).

The Plan may accept an in-kind transfer of assets from Mariner’s 401(k) Plan, as determined by the Committee.

Loans in Mariner’s 401(k) Plan will be transferred to the Plan. The repayment schedule of the loans may be modified to accommodate the Borrower’s new pay schedule. Participants cannot borrow from the Plan again until all prior loans have been repaid.

Individuals who were employed by Mariner or related companies and become Covered Employees on the Closing Date will be deemed to have elected to make Participant Contributions to this Plan at the same rate that they had been making similar contributions to Mariner’s 401(k) Plan immediately before the plans’ merger. If any such individual was not contributing to Mariner’s 401(k) Plan when the plan merger occurred, he will not be automatically enrolled in the Plan, even if he was hired by Mariner as recently as one day before the plans’ merger.

If (a) the Participant was an employee of Mariner on the Closing Date, (b) his severance from employment occurs on or before June 30, 2011, (c) Apache decided to terminate the Participant or the Participant decided not to accept Apache’s offer of employment, and (d) the Participant’s termination is not for cause, then the Participant’s Old Mariner Accounts shall become fully vested upon his severance from employment.

— END OF APPENDIX C —

APPENDIX D

Apache International Employment Inc.

Introduction

Apache and its subsidiaries have certain employees who are routinely transferred to different sites around the world. As explained below, any Apache International Employment Inc. (“AIEI”) employee who is a US person (one who is a US citizen or a US resident, or who performs services for AIEI that generate US-source income) will generally be eligible to participate in this Plan while he remains a US person. AIEI employees who are not US persons generally participate in the Apache Corporation International Retirement Savings Plan.

Eligibility to Participate

Notwithstanding section 1.15, the term “Covered Employee” for any Employee of AIEI shall only include an AIEI Employee after May 15, 2014 who is a US citizen or US resident, or is a nonresident alien performing services for AIEI whose remuneration from AIEI is treated as income from sources within the United States pursuant to Code §872, with the following exceptions.

When Participant Contributions Begin

Participant Contributions can be made from any paycheck of a Covered Employee after this amendment is signed.

Calculation of Match

The Company Matching Contribution for a Covered Employee shall be determined pursuant to section 3.2 of the Plan, based on his Participant Contributions for the Plan Year and his “Includable Compensation” for the Plan Year. “Includable Compensation” includes Compensation paid only while the Participant is a Covered Employee, and shall include a Participant’s entire final paycheck that contains any funds attributable to services performed as a Covered Employee.

When Benefits Cease to Be Earned

When an Employee of AIEI ceases to be a Covered Employee, Participant Contributions will be withheld (pursuant to his then-existing deferral election) from Compensation from his entire final paycheck that contains funds attributable to services performed as a Covered Employee.

— END OF APPENDIX D —