8-K

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

Current Report
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 12, 2010

APACHE CORPORATION

(Exact name of registrant as specified in Charter)

Delaware
(State or Other Jurisdiction
of Incorporation) 1-4300
(Commission
File Number) 41-0747868
(I.R.S. Employer
Identification Number)

2000 Post Oak Boulevard
Suite 100
Houston, Texas 77056-4400
(Address of Principal Executive Offices)

Registrant’s telephone number, including area code: (713) 296-6000

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

þ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2 (b))

o Pre-Commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4 (c))

Item 8.01. Other Events

On April 15, 2010, Apache Corporation (“Apache”), a Delaware corporation, and Mariner Energy, Inc. (“Mariner”), a Delaware corporation, issued a combined press release announcing the execution of a Merger Agreement among Apache, ZMZ Acquisitions LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Apache (“Merger Sub”), and Mariner (the “Merger Agreement”). Under the terms of the Merger Agreement, Mariner will merge with and into Merger Sub, with Merger Sub surviving the merger as a wholly-owned subsidiary of Apache. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

In addition, on April 12, 2010, Apache announced that it had agreed to acquire Devon Energy Corporation’s (“Devon”) oil and gas assets on the Gulf of Mexico Shelf for $1.05 billion. A copy of the press release is attached hereto as Exhibit 99.2 and is incorporated by reference herein.

Additional Information Regarding Transaction with Mariner

This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval. Apache will file with the Securities and Exchange Commission (“SEC”) a registration statement on Form S-4 that will include a proxy statement of Mariner that also constitutes a prospectus of Apache. A definitive proxy statement/prospectus will be mailed to stockholders of Mariner. Apache and Mariner also plan to file other documents with the SEC regarding the proposed transaction. INVESTORS AND SECURITY HOLDERS OF MARINER ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS THAT WILL BE FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION. Such documents are not currently available. Investors and security holders will be able to obtain the documents (when available) free of charge at the SEC’s web site, www.sec.gov. Copies of the documents filed with the SEC by Apache will be available free of charge on Apache’s website at www.apachecorp.com under the tab “Investors” or by contacting Apache’s Investor Relations Department at 713-296-6000. Copies of the documents filed with the SEC by Mariner will be available free of charge on Mariner’s website at www.mariner-energy.com under the tab “Investor Information” or by contacting Mariner’s Investor Relations Department at 713-954-5558. You may also read and copy any reports, statements and other information filed with the SEC at the SEC public reference room at 100 F

Street N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at (800) 732-0330 or visit the SEC’s website for further information on its public reference room.

Apache, Mariner, their respective directors and executive officers, and other persons may be deemed, under SEC rules, to be participants in the solicitation of proxies from stockholders of Mariner in connection with the proposed transaction. Information regarding Apache’s directors and officers can be found in its proxy statement filed with the SEC on March 31, 2010, and information regarding Mariner’s directors and officers can be found in its proxy statement filed with the SEC on April 1, 2010. Additional information regarding the participants in the proxy solicitation and a description of their direct and indirect interests in the transaction, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC when they become available.

Forward-Looking Statements

Statements in this document include “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The opinions, forecasts, projections, future plans or other statements other than statements of historical fact, are forward-looking statements. We can give no assurance that such expectations will prove to have been correct. Actual results could differ materially as a result of a variety of risks and uncertainties, including: the timing to consummate the proposed agreement with Mariner; the risk that a condition to closing of the proposed agreement may not be satisfied; the risk that a regulatory approval that may be required for the proposed agreement is not obtained or is obtained subject to conditions that are not anticipated; negative effects from the pendency of the merger; our ability to achieve the synergies and value creation contemplated by the proposed agreement; our ability to promptly and effectively integrate the merged businesses; and the diversion of management time on agreement-related issues. Other factors that could materially affect actual results are discussed in Apache’s and Mariner’s most recent Forms 10-K as well as each company’s other filings with the SEC available at the SEC’s website at www.sec.gov. Actual results may differ materially from those expected, estimated or projected. Forward-looking statements speak only as of the date they are made, and we undertake no obligation to publicly update or revise any of them in light of new information, future events or otherwise.

Item 9.01. Financial Statements and Exhibits

(c) Exhibits.

Exhibit No.		Description
	99.1	Press Release dated April 15, 2010, “Apache Gains Strategic Position in Deepwater Gulf with Mariner Merger”
	99.2	Press Release dated April 12, 2010, “Apache to Acquire Devon’s Gulf of Mexico Shelf Assets”

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

	APACHE CORPORATION
Date: April 15, 2010	/s/ Roger B. Plank
	Roger B. Plank, President
	(Principal Financial Officer)

INDEX TO EXHIBITS

Exhibit No.		Description
	99.1	Press Release dated April 15, 2010, “Apache Gains Strategic Position in Deepwater Gulf with Mariner Merger”
	99.2	Press Release dated April 12, 2010, “Apache to Acquire Devon’s Gulf of Mexico Shelf Assets”

EX-99.1

EXHIBIT 99.1

CONTACTS:

(Media):	Bill Mintz	(713) 296-7276
	Robert Dye	(713) 296-6662
(Investor):	Tom Chambers	(713) 296-6685
	Rob Rayphole	(713) 296-6160
(Web site):	www.apachecorp.com

APACHE GAINS STRATEGIC POSITION IN DEEPWATER GULF WITH MARINER MERGER

     Houston, April 15, 2010 — Apache Corporation (NYSE, Nasdaq: APA) and Mariner Energy (NYSE: ME) today announced that they have entered into a merger agreement that will combine Apache’s global reach and resources with Mariner’s track record of successful deepwater exploration and its resource potential.

     “This is a strategic step and a natural extension into the deepwater Gulf for Apache,” said G. Steven Farris, Apache’s chairman and chief executive officer. “Mariner provides an exciting new platform for growth in the deepwater and complements our strengths in the Gulf Shelf and the Permian Basin. Based on our experience working with the Mariner team, we also believe the two companies will make an excellent cultural fit.”

     “The combination with Apache is an excellent outcome for Mariner’s stakeholders. Our shareholders will be rewarded for their faith and support in our company with the opportunity to further benefit from the upside provided from the merger. Our partners will work with a world-class company with the financial and technical resources to fully exploit our assets. Our employees will benefit from the opportunities provided in a large company with values similar to Mariner’s,” said Scott D. Josey, Mariner’s chairman, chief executive officer and president.

     Under the agreement, Mariner shareholders will receive, in aggregate, 0.17043 of a share of Apache common stock and $7.80 in cash for each outstanding share of Mariner’s common stock, subject to an election feature and proration. At Apache’s closing stock price of $108.06 on April 14, 2010, the transaction values Mariner’s shares at $26.22 per share or approximately $2.7 billion. Apache also will assume $1.2 billion in debt.

     In February, Mariner produced 63,000 barrels of oil equivalent (boe) per day from the Gulf Shelf and deepwater, the Permian Basin and unconventional onshore plays. At year-end 2009, Mariner had estimated proved reserves of 181 million boe (47 percent liquid hydrocarbons) as well as unbooked resource potential of 2 billion boe.

     Mariner’s deepwater portfolio includes nearly 100 blocks, seven discoveries in development — including interests in Lucius and Heidelberg — and more than 50 prospects.

     “We have considered extending our Gulf of Mexico operations into the deepwater for a number of years,” Farris said. “This is the right set of assets and the right time for Apache to expand its deepwater presence.

     “Mariner brings an inventory of developments and prospects that will jump-start our position in the deepwater Gulf; Apache’s financial resources will maximize the value of the portfolio,” he said. “It’s the right time because recent advances in seismic technology and continued enhancements in facilities design have reduced the risks in one of the world’s most prolific oil exploration basins.”

     Apache and Mariner teamed up in the 2008 deepwater Geauxpher discovery and development at Garden Banks 462. “Mariner’s skilled, experienced professionals share our values and sense of urgency,” Farris said.

     In addition to Geauxpher, Apache has drilled several deepwater discoveries in Egypt and Western Australia.

     Mariner also has more than 240 blocks on the Gulf Shelf and more than 200,000 net acres across several emerging onshore plays. “Mariner’s Gulf Shelf and Permian assets are both excellent fits with our existing core areas,” Farris said. “These fields provide strong cash flow, drilling inventory and upside potential.”

     Earlier this week, Apache announced it will acquire additional Gulf Shelf assets from Devon Energy Corporation that add production of 19,000 boe per day with year-end 2009 estimated proved and probable reserves of 83 million boe across 158 blocks.

     Apache’s last corporate transaction, with the Phoenix Resource Companies in 1996, established Apache as an operator in Egypt and set the stage for the region to become one of the company’s principal growth areas.

     “Combining with Mariner enhances Apache’s global portfolio, which is balanced in terms of commodity mix, geography and geology,” Farris said. “This transaction is similar to our earlier strategic steps, bringing near-term production and cash flow as well as long-term upside potential from a large acreage position with identified exploration opportunities.”

     The transaction is subject to approval by Mariner’s shareholders and customary regulatory approvals. Completion of the transaction is expected in the third quarter of 2010.

     Apache’s financial advisers in this transaction were Goldman, Sachs & Co. and J.P. Morgan Securities. Mariner was advised by Credit Suisse Securities (USA) LLC.

     Apache Corporation is an oil and gas exploration and production company with operations in the United States, Canada, Egypt, the United Kingdom North Sea, Australia and Argentina.

     Mariner Energy is an independent oil and gas exploration, development, and production company headquartered in Houston, Texas, with principal operations in the Permian Basin, Gulf Coast and the Gulf of Mexico. For more information about Mariner, visit the company’s Web site at www.mariner-energy.com.

     NOTE: Apache will conduct a conference call to discuss the Mariner Energy merger agreement at 9 a.m. Central time on Thursday, April 15. The call will be webcast from Apache’s Web site, www.apachecorp.com. The webcast replay and podcast will be archived on Apache’s Web site. The conference call will be available for delayed playback by telephone for one week beginning at approximately 11 a.m. on April 15. To access the telephone playback, dial (719) 457-0820 and provide Apache’s confirmation code, 3254008.

     Additional information about this transaction will be posted on Apache’s Web site, www.apachecorp.com/mariner. Apache also posts other announcements, updates, investor information and copies of all press releases on its Web site.

Additional Information

     This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval. Apache will file with the Securities and Exchange Commission (“SEC”) a registration statement on Form S-4 that will include a proxy statement of Mariner that also constitutes a prospectus of Apache. A definitive proxy statement/prospectus will be mailed to stockholders of Mariner. Apache and Mariner also plan to file other documents with the SEC regarding the proposed transaction. INVESTORS AND SECURITY HOLDERS OF MARINER ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER DOCUMENTS THAT WILL BE FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION. Such documents are not currently available. Investors and security holders will be able to obtain the documents (when available) free of charge at the SEC’s web site, www.sec.gov. Copies of the documents filed with the SEC by Apache will be available free of charge on Apache’s website at www.apachecorp.com under the tab “Investors” or by contacting Apache’s Investor Relations Department at 713-296-6000. Copies of the documents filed with the SEC by Mariner will be available free of charge on Mariner’s website at www.mariner-energy.com under the tab “Investor Information” or by contacting Mariner’s Investor Relations Department at 713-954-5558. You may also read and copy any reports, statements and other information filed with the SEC at the SEC public reference room at 100 F Street N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at (800) 732-0330 or visit the SEC’s website for further information on its public reference room.

     Apache, Mariner, their respective directors and executive officers and other persons may be deemed, under SEC rules, to be participants in the solicitation of proxies from stockholders of Mariner in connection with the proposed transaction. Information regarding Apache’s directors and officers can be found in its proxy statement filed with the SEC on March 31, 2010 and information regarding Mariner’s directors and officers can be found in its proxy statement filed with the SEC on April 1, 2010. Additional information regarding the participants in the proxy solicitation and a description of their direct and indirect interests in the transaction, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC when they become available.

Forward-Looking Statements

Statements in this document include “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The opinions, forecasts, projections, future plans or other statements other than statements of historical fact, are forward-looking statements. We can give no assurance that such expectations will prove to have been correct. Actual results could differ materially as a result of a variety of risks and uncertainties, including: the timing to consummate the proposed agreement; the risk that a condition to closing of the proposed agreement may not be satisfied; the risk that a regulatory approval that may be required for the proposed agreement is not obtained or is obtained subject to conditions that are not anticipated; negative effects from the pendency of the merger; our ability to achieve the synergies and value creation contemplated by the proposed agreement; our ability to promptly and effectively integrate the merged businesses; and the diversion of management time on agreement-related issues. Other factors that could materially affect actual results are discussed in Apache’s and Mariner’s most recent 10-Ks as well as each company’s other filings with the SEC available at the SEC’s website at www.sec.gov. Actual results may differ materially from those expected, estimated or projected. Forward-looking statements speak only as of the date they are made, and we undertake no obligation to publicly update or revise any of them in light of new information, future events or otherwise.

EX-99.2

EXHIBIT 99.2

CONTACTS:

(Media):	Bill Mintz	(713) 296-7276
	Robert Dye	(713) 296-6662
(Investor):	Tom Chambers	(713) 296-6685
	Rob Rayphole	(713) 296-6160
(Web site):	www.apachecorp.com

APACHE TO ACQUIRE DEVON’S GULF OF MEXICO SHELF ASSETS

$1.05 billion transaction brings production of 19,000 equivalent barrels per day, drilling upside

     Houston, April 12, 2010 — Apache Corporation (NYSE, Nasdaq: APA) said today that it has agreed to acquire Devon Energy Corporation’s oil and gas assets on the Gulf of Mexico Shelf for $1.05 billion. Apache estimated net proved and probable reserves of 83 million barrels of oil equivalent at year-end 2009.

     The properties are projected to produce 9,500 barrels of liquid hydrocarbons and 55 million cubic feet of gas per day (net) after closing — the same balance of liquids and natural gas in Apache’s current worldwide production. Closing is expected in early June.

     Liquid hydrocarbons also are expected to contribute more than 70 percent of the projected revenues from the acquired properties. About half of the estimated proved reserves of 41 million barrels equivalent are oil and natural gas liquids.

     “Devon’s exit from the Gulf of Mexico creates a great opportunity for Apache to add one of the best remaining Shelf asset portfolios to our existing core area,” said G. Steven Farris, Apache’s chairman and chief executive officer.

     “These are well-maintained, high-quality assets that fit well with Apache’s existing infrastructure and play to the strengths that come with our experience operating on the shelf — exploiting the current production base and capturing the upside potential,” said Jon Jeppesen, executive vice president and leader of Apache’s Gulf Coast Region. “Many of these properties are geologically complex fields that contain large structures with multiple pay intervals that we believe are under-exploited. The prospect inventory includes high-potential trend exploration opportunities in the Norphlet play and highly prospective exploratory acreage off the Texas coast.”

     “At 3.7 times estimated cash flow, this transaction is immediately additive to Apache’s per-share earnings and cash flow, generating excess cash flow that can be used to further Apache’s growth through continued development of our global exploration program,” Farris said.

     Projected daily production from the acquired assets for the remainder of 2010 equals 3 percent of Apache’s fourth-quarter 2009 worldwide daily production. When the transaction is completed, the Gulf Shelf’s share of Apache’s estimated worldwide production will be slightly less than 20 percent.

     Apache is the largest held-by-production acreage owner and the second-largest producer in Gulf waters less than 1,200 feet deep. The acquired assets comprise 477,000 net acres across 158 blocks. The fields have 80 platforms and 211 production caissons in waters to 450 feet deep.

     Seven major field areas hold 90 percent of the proved reserves. Devon operates 75 percent of the production. Based on initial evaluation, Apache has identified 79 recompletion opportunities and 26 drilling prospects across the acquired assets.

     Apache will fund the acquisition primarily from existing cash balances supplemented with commercial paper. Apache has hedged a portion of the production for three years using swaps and collars to protect the economics of the transaction, which is effective Jan. 1.

     Completion of the transaction is subject to preferential rights to purchase held by the other working interest owners in the properties as well as customary closing conditions and regulatory approvals.

     Additional information about this transaction is posted on Apache’s Web site, www.apachecorp.com, along with other announcements, updates, investor information and copies of all press releases.

     Apache Corporation is an oil and gas exploration and production company with operations in the United States, Canada, Egypt, the United Kingdom North Sea, Australia and Argentina.

     This news release contains certain “forward-looking statements” within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995 including, without limitation, expectations, beliefs, plans and objectives regarding production and exploration activities. Any matters that are not historical facts are forward-looking and, accordingly, involve estimates, assumptions, risks and uncertainties, including, without limitation, risks, uncertainties and other factors discussed in our most recently filed Annual Report on Form 10-K, on our Web site and in our other public filings and press releases. There is no assurance that Apache’s expectations will be realized, and actual results may differ materially from those expressed in the forward-looking statements. We assume no duty to update these statements as of any future date.

     Effective January 1, 2010, the United States Securities and Exchange Commission (SEC) now permits oil and gas companies, in their filings with the SEC, to disclose not only “proved” reserves (i.e., quantities of oil and gas that are estimated to be recoverable with a high degree of confidence), but also “probable” reserves (i.e., quantities of oil and gas that are as likely as not to be recovered) as well as “possible” reserves (i.e., additional quantities of oil and gas that might be recovered, but with a lower probability than probable reserves). Statements of reserves are only estimates and may not correspond to the ultimate quantities of oil and gas recovered. Any reserve estimates provided in this presentation that are not specifically designated as being estimates of proved reserves may include estimated reserves not necessarily calculated in accordance with, or contemplated by, the SEC’s latest reserve reporting guidelines. Investors are urged to consider closely the disclosure in Apache’s Annual Report on Form 10-K for the fiscal year ended December 31, 2009, available from Apache at www.apachecorp.com or by writing Apache at: 2000 Post Oak Blvd., Suite 100, Houston, Texas 77056 (Attn: Corporate Secretary). You can also obtain this report from the SEC by calling 1-800-SEC-0330 or from the SEC’s website at www.sec.gov.

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