UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 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): July 14, 2006

WESTERN GAS RESOURCES, INC.
(Exact Name of Registrant as Specified in Charter)

(303) 452-5603
(Registrant's telephone number, including area code)

N.A.
(Former Name or Former Address, if Changed Since Last Report)

        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):

o

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

ý

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 July 14, 2006, Western Gas Resources, Inc. issued a press release announcing that it will hold a special meeting of its stockholders on August 23, 2006 to vote on the proposed merger of Western with a wholly owned subsidiary of Anadarko Petroleum Corp. and that a record date of July 21, 2006 had been set in connection with the special meeting. The press release is furnished as Exhibit 99.1 to this Form 8-K.

Item 9.01. Financial Statements and Exhibits.

(d)

Exhibits.

        A list of exhibits filed herewith is contained on the Exhibit Index which immediately precedes such exhibits and is incorporated herein by reference.

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 hereunto duly authorized.

EXHIBIT INDEX

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Item 8.01. Other Events.
Item 9.01. Financial Statements and Exhibits.