Summary of MARINER ENERGY INC

Item 1.01 Entry into a Material Definitive Agreement, and Item 2.03 Creation of
a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.
Mariner Energy, Inc. ("Mariner") entered into Amendment No. 7, dated as of December 12, 2008, among Mariner and Mariner Energy Resources, Inc., as borrowers, the Lenders (as defined in the Credit Agreement described below), and Union Bank of California, N.A., as administrative agent and as issuing lender for such Lenders (the "Amendment"), which further amends the Amended and Restated Credit Agreement, dated as of March 2, 2006, among the same parties (as so amended, the "Credit Agreement"). The Credit Agreement provides for a senior secured revolving credit facility of $1 billion, including up to $50 million in letters of credit, subject to a borrowing base which is redetermined periodically. The Amendment affirms the borrowing base of $850 million as of December 12, 2008 and provides that the borrowing base redetermination scheduled for spring 2009 be made in February 2009.
A copy of the Amendment is attached as Exhibit 4.1 and incorporated herein by reference. The above description of the Credit Agreement is a summary and is qualified in its entirety by the complete text of the Amendment and the Credit Agreement which previously was filed.
Item 9.01 Financial Statements and Exhibits
(d) Exhibits.

 No.     Description

 4.1     Amendment No. 7, dated as of December 12, 2008, among Mariner Energy,
         Inc. and Mariner Energy Resources, Inc., as Borrowers, the Lenders (as
         defined in the Amended and Restated Credit Agreement, dated as of
         March 2, 2006, among Mariner Energy, Inc. and Mariner Energy Resources,
         Inc., as Borrowers, the Lenders party thereto from time to time, as
         Lenders, and Union Bank of California, N.A., as Administrative Agent and
         as Issuing Lender, as amended), and Union Bank of California, N.A., as
         Administrative Agent for such Lenders and as Issuing Lender for such
         Lenders.

 4.2*    Amended and Restated Credit Agreement, dated as of March 2, 2006, among
         Mariner Energy, Inc. and Mariner Energy Resources, Inc., as Borrowers,
         the Lenders party thereto from time to time, as Lenders, and Union Bank
         of California, N.A., as Administrative Agent and as Issuing Lender
         (incorporated by reference to Exhibit 4.1 to Mariner's Form 8-K filed on
         March 3, 2006).

 4.3*    Amendment No. 1 and Consent, dated as of April 7, 2006, among Mariner
         Energy, Inc. and Mariner Energy Resources, Inc., as Borrowers, the
         Lenders party thereto, and Union Bank of California, N.A., as
         Administrative Agent for such Lenders and as Issuing Lender for such
         Lenders (incorporated by reference to Exhibit 4.1 to Mariner's Form 8-K
         filed on April 13, 2006).

 4.4*    Amendment No. 2, dated as of October 13, 2006, among Mariner Energy,
         Inc. and Mariner Energy Resources, Inc., as Borrowers, the Lenders party
         thereto, and Union Bank of California, N.A., as Administrative Agent for
         such Lenders and as Issuing Lender for such Lenders (incorporated by
         reference to Exhibit 4.1 to Mariner's Form 8-K filed on October 18,
         2006).

 4.5*    Amendment No. 3 and Consent, dated as of April 23, 2007, among Mariner
         Energy, Inc. and Mariner Energy Resources, Inc., as Borrowers, the
         Lenders party thereto, and Union Bank of California, N.A., as
         Administrative Agent for such Lenders and as Issuing Lender for such
         Lenders (incorporated by reference to Exhibit 4.1 to Mariner's Form 8-K
         filed on April 24, 2007).

 4.6*    Amendment No. 4, dated as of August 24, 2007, among Mariner Energy, Inc.
         and Mariner Energy Resources, Inc., as Borrowers, the Lenders party
         thereto, and Union Bank of California, N.A., as Administrative Agent for
         such Lenders and as Issuing Lender for such Lenders (incorporated by
         reference to Exhibit 4.1 to Mariner's Form 8-K filed on August 27,
         2007).

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 No.     Description

 4.7*    Amendment No. 5 and Agreement, dated as of January 31, 2008, among
         Mariner Energy, Inc. and Mariner Energy Resources, Inc., as Borrowers,
         the Lenders party thereto, and Union Bank of California, N.A., as
         Administrative Agent for such Lenders and as Issuing Lender for such
         Lenders (incorporated by reference to Exhibit 4.1 to Mariner's Form 8-K
         filed on February 5, 2008).

 4.8*    Master Assignment, Agreement and Amendment No. 6, dated as of June 2,
         2008, among Mariner Energy, Inc. and Mariner Energy Resources, Inc., as
         Borrowers, the Lenders party thereto, and Union Bank of California,
         N.A., as Administrative Agent for such Lenders and as Issuing Lender for
         such Lenders (incorporated by reference to Exhibit 4.1 to Mariner's
         Form 8-K filed on June 3, 2008).

* Incorporated by reference as indicated.

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