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                                                                     Exhibit 5.1

                     [LETTERHEAD OF VINSON & ELKINS L.L.P.]



                                  April 8, 2003

Chesapeake Energy Corporation
6100 North Western Avenue
Oklahoma City, Oklahoma 73118

Ladies and Gentlemen:

     We have acted as counsel for Chesapeake Energy Corporation, an Oklahoma
corporation (the "Company") and certain of its subsidiaries with respect to with
the preparation of the Registration Statement on Form S-4 (the "Registration
Statement") filed with the Securities and Exchange Commission (the "Commission")
in connection with the registration by the Company under the Securities Act of
1933, as amended (the "Securities Act") of (i) the offer and exchange by the
Company (the "Exchange Offer") of $300,000,000 aggregate principal amount of its
7.50% Senior Notes due 2013 (the "Initial Notes"), for a new series of notes
bearing substantially identical terms and in like principal amount (the
"Exchange Notes") and (ii) the guarantees (the "Guarantees") of certain
subsidiaries of the Company listed in the Registration Statement as guarantors
(the "Subsidiary Guarantors") of the Initial Notes and the Exchange Notes. The
Initial Notes and the Exchange Notes are collectively referred to herein as the
"Notes". The Initial Notes were issued, and the Exchange Notes will be issued,
under an Indenture dated as of March 5, 2003 among the Company, the Subsidiary
Guarantors and The Bank of New York, as Trustee (the "Indenture"). The Exchange
Offer will be conducted on such terms and conditions as are set forth in the
prospectus contained in the Registration Statement to which this opinion is an
exhibit.

     We have examined originals or copies, certified or otherwise identified to
our satisfaction, of (i) the Registration Statement, (ii) the Indenture and
(iii) such other certificates, statutes and other instruments and documents as
we considered appropriate for purposes of the opinions hereafter expressed. In
connection with this opinion, we have assumed that the Registration Statement,
and any amendments thereto (including post-effective amendments), will have
become effective and the Exchange Notes will be issued and sold in compliance
with applicable federal and state securities laws and in the manner described in
the Registration Statement.

     Based on the foregoing, we are of the opinion that when the Exchange Notes
have been duly executed, authenticated, issued and delivered in accordance with
the provisions of the Indenture, (i) such Exchange Notes will be legally issued
and will constitute valid and binding obligations of the Company enforceable
against the Company in accordance with their terms, and (ii) the Guarantees of
the Subsidiary Guarantors remain valid and binding obligations of such
subsidiaries, enforceable against the Company and each such Subsidiary Guarantor
in accordance with their terms, except in each case as such enforcement is
subject to any applicable bankruptcy, insolvency, reorganization or other law
relating to or affecting creditors' rights generally and general principles of
equity.

     We express no opinions concerning (a) the validity or enforceability of any
provisions contained in the Indenture that purport to waive or not give effect
to rights to notices, defenses, subrogation or other rights or benefits that
cannot be effectively waived under applicable law; or (b) the enforceability of
indemnification provisions to the extent they purport to relate to liabilities
resulting from or based upon negligence or any violation of federal or state
securities or blue sky laws.

     We are members of the bar of the State of Texas. We have relied as to
matters of Oklahoma law on the opinion of Commercial Law Group, P.C., which
opinion is also filed as an exhibit to the Registration Statement. The

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opinions expressed herein are limited exclusively to the federal laws of the
United States of America, the laws of the State of New York and, in reliance on
the opinion of Commercial Law Group, P.C., the laws of the State of Oklahoma,
and we are expressing no opinion as to the effect of the laws of any other
jurisdiction, domestic or foreign.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our firm name in the prospectus forming
a part of the Registration Statement under the caption "Legal Matters." By
giving such consent, we do not admit that we are within the category of persons
whose consent is required under Section 7 of the Securities Act or the rules and
regulations of the Commission issued thereunder.

                                                  Very truly yours,

                                                  /s/ Vinson & Elkins L.L.P.
                                                  ------------------------------
                                                  Vinson & Elkins L.L.P.