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                                                                     EXHIBIT 2.1

                                February 4, 1999



PETROLEUM DEVELOPMENT CORPORATION
9720-B Candelaria N.E.
Albuquerque, NM  87112

ATTENTION:  MR. JIM C. JOHNSON, JR.

                       RE:      PURCHASE PROPOSAL
                                H.E. WHITE UNIT
                                FREESTONE COUNTY, TEXAS

Dear Jim:

         In response to our phone conversation about the sale of 100% of our
working interest in the H.E. White Unit in Freestone County, Texas, Venus hereby
makes the following counterproposal subject to the following terms and
conditions:

         1. Price: Venus hereby agrees to sell its working interest in the H.E.
         White Unit for $1,150,000.

         2. Payment for Wells: It is recognized that there are 3 wells drilled
         and completed on the referenced unit and it is understood and agreed
         that Venus will be responsible for all payments on the #1 and #2 wells
         through completion and operations through December 31, 1998. As to the
         H.E. White #3 well and future wells, PEDCO shall be responsible for the
         drilling, completing and operating expense for said wells and shall be
         responsible for all operating costs on all wells after December 31,
         1998.

         3. Effective Date: The effective date of the purchase shall be midnight
         (12:00 p.m.) December 31, 1998. In the event Venus receives any income
         attributable to the interest herein conveyed for production of oil
         and/or gas which was produced after the effective date hereof, Venus
         shall immediately pay PEDCO such sums of money. In the event Venus has
         paid operating or other costs and charges attributable to the interest
         herein conveyed after the effective date hereof and prior to closing,
         Venus shall immediately furnish PEDCO evidence of the same and PEDCO
         shall immediately reimburse Venus such sums of money. At the time of
         closing, all operating expenses and other costs shall be paid in full
         by Venus as of that effective date. All operating and other costs and
         charges


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         after the effective date shall become PEDCO's responsibility. Taxes and
         other charges will be prorated as to the effective date.

         4. Closing: The closing contemplated by this offer shall take place in
         Venus' offices in San Antonio, or some other mutually acceptable
         location on or before February 12, 1999. At closing, PEDCO will pay to
         Venus, by check, the purchase price specified in paragraph 1 above. At
         closing, Venus shall execute and deliver to PEDCO the necessary
         instruments to convey in a mutually satisfactory form, with no warranty
         of title, except, by, through and under Venus, covering 100% of Venus'
         interest in the properties, equipment and oil, gas and other mineral
         leases described in that certain Declaration of Gas Unit, which is
         recorded in Volume 607, Page 506 of the Deed Records of Freestone
         County, Texas.

         5. Warranty: The subject property will be, at the time of conveyance to
         PEDCO, free and clear of all liens, charges and encumbrances created by
         Venus. The Assignment and Bill of Sale or other instrument of
         conveyance shall be without warranty of title, except by, through and
         under Venus, but not otherwise. Prior to closing, PEDCO shall have the
         opportunity to accept or reject title to the properties, equipment and
         oil, gas and mineral leases described in that certain Declaration of
         Gas Unit, which is recorded in Volume 607, Page 506 of the Deed Records
         of Freestone County, Texas. All personal property and equipment shall
         be sold as is and where is, with all faults and without any warranties
         whatsoever, either express or implied.

         6. Interest Delivered: Venus believes that it owns a 25% working
         interest and an 18.51% net revenue interest before payout and a
         21.1804% working interest and a 16.51% net revenue interest after
         payout of the wells drilled on the H.E. White Unit (assuming back-in
         elections are made). There are currently three farmout agreements
         covering four tracts within the unit that have a large override that
         may be converted to a working interest at payout. These working
         interest and net revenue interest numbers are based off the enclosed
         schedule that was generated from the division order covering the H.E.
         White #1 well, and at this time there is a new division order title
         opinion being prepared by Anadarko covering this tract that will
         document the working interest and net revenue interest covering this
         tract. Venus does not warrant the working interest or net revenue
         interest set forth above, therefore, PEDCO agrees to check the records
         thoroughly and make its own determination as to the interest that Venus
         owns.

         In addition, in an Anadarko Title Opinion dated June 10, 1998, an
         overriding royalty interest of .24% has been deducted from the Venus
         net revenue interest. This overriding royalty interest was assigned out
         to employees of the company we acquired. We feel that this overriding


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         royalty has reverted back to Venus, but because record title is not
         clear on the ownership of this interest, we have deducted it from the
         net revenue interest stated above. The parties hereto agree that Venus
         will keep this overriding royalty interest and it will not be
         considered part of this transaction.

         7. Entire Agreement: This Agreement constitutes the entire agreement
         between the parties hereto and supersedes all prior agreements,
         negotiations and understandings. Any amendment to this Purchase
         Proposal shall be done only by written instrument executed by both
         PEDCO and Venus. This agreement is binding upon and shall inure to the
         benefit of the parties hereto, their respective heirs, successors and
         assigns.

         If you concur with the terms and conditions set forth above, please
indicate your acceptance by executing in the space provided below and returning
one signed copy to the undersigned by 5:00 p.m. CST, February 4, 1999. At
5:00 p.m. CST, February 4, 1999, this proposal shall automatically terminate and
become null and void.

                                          Very truly yours,

                                           /s/ JOHN Y. AMES

                                          John Y. Ames
                                          President and Chief Operating Officer

ACCEPTED and AGREED TO this 
_____ day of ______________, 1999.

PETROLEUM DEVELOPMENT CORPORATION


By: /s/ JIM C. JOHNSON JR.
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Printed Name: JIM C. JOHNSON JR.
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JYA/dak