Document:

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                                                                   EXHIBIT 4.1.2

                         SEVENTH SUPPLEMENTAL INDENTURE
              TO INDENTURE DATED MARCH 15, 1997 (7 7/8% SECURITIES)

               SEVENTH SUPPLEMENTAL INDENTURE dated as of September 12, 2001,
among CHESAPEAKE ENERGY CORPORATION, an Oklahoma corporation (the "Company"),
the SUBSIDIARY GUARANTORS listed as signatories hereto, BANK OF NEW YORK,
successor to United States Trust Company of New York, as Trustee to the
Indenture (the "Trustee"), GOTHIC ENERGY CORPORATION, an Oklahoma corporation
("GEC"), GOTHIC PRODUCTION CORPORATION, an Oklahoma corporation ("GPC"), NOMAC
DRILLING CORPORATION, an Oklahoma corporation ("NDC"), ARKOMA PITTSBURG HOLDING
CORPORATION, an Oklahoma corporation ("APHC"), CHESAPEAKE-STAGHORN ACQUISITION
L.P., an Oklahoma limited partnership ("CSALP"), and CHESAPEAKE MOUNTAIN FRONT
CORP., an Oklahoma corporation ("CMFC").

               WHEREAS, the Board of Directors of the Company has adopted
resolutions designating GEC, GPC, NDC, APHC, CSALP and CMFC as Restricted
Subsidiaries;

               WHEREAS, contemporaneously herewith, there are being delivered to
the Trustee an Opinion of Counsel and Officers' Certificate proper in form and
substance;

               WHEREAS, Section 9.1 of the Indenture provides, among other
things, that the Trustee, the Subsidiary Guarantors and the Company may amend or
supplement the Indenture without notice to or consent of any Holder to reflect
the addition of any Subsidiary Guarantor, as provided for by the Indenture; and

               WHEREAS, the execution and delivery of this Seventh Supplemental
Indenture have been duly authorized by the Company, the Subsidiary Guarantors,
GEC, GPC, NDC, APHC, CSALP and CMFC and all actions necessary to make this
Seventh Supplemental Indenture a valid and binding instrument according to its
terms and the terms of the Original Indenture have been performed.

               NOW, THEREFORE, BY THIS SEVENTH SUPPLEMENTAL INDENTURE, for and
in consideration of the premises and of the mutual covenants herein contained
and for other valuable considerations, the receipt whereof is hereby
acknowledged, the Company, the Subsidiary Guarantors, GEC, GPC, NDC, APHC, CSALP
and CMFC covenant and agree with the Trustee, for the equal benefit of all
present and future Holders of the Securities, as follows:

                                    ARTICLE I

                                   DEFINITIONS

               SECTION 1.1 The definitions set forth in or incorporated by
reference in Article I of the Indenture shall be applicable to this Seventh
Supplemental Indenture, as fully and to

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the same extent as if set forth herein, except as otherwise expressly provided
herein. As used in this Seventh Supplemental Indenture, the following terms
shall have the following meanings:

               "Indenture" means the Original Indenture, as amended by this
Seventh Supplemental Indenture, relating to the Securities.

               "Original Indenture" means the Indenture dated as of March 15,
1997, among the Company, the Subsidiary Guarantors listed as signatories thereto
and the Trustee, relating to the Securities, as amended by: (i) that certain
First Supplemental Indenture dated as of December 17, 1997, (ii) that certain
Second Supplemental Indenture dated as of February 16, 1998, (iii) that certain
Third Supplemental Indenture dated as of April 22, 1998, (iv) that certain
Fourth Supplemental Indenture dated as of July 1, 1998, (v) that certain Fifth
Supplemental Indenture dated as of November 19, 1999, and (vi) that certain
Sixth Supplemental Indenture dated as of December 31, 1999.

                                   ARTICLE II

                        ADDITION OF SUBSIDIARY GUARANTORS

               SECTION 2.1 As a Subsidiary Guarantor, GEC, GPC, NDC, APHC, CSALP
and CMFC hereby: (a) unconditionally guarantee to each Holder and to the Trustee
the due and punctual payment of the principal of, premium, if any, and interest
on the Securities and all other amounts due and payable under the Indenture and
the Securities by the Company, whether at maturity, by acceleration, redemption,
repurchase or otherwise including, without limitation, interest on the overdue
principal of, premium, if any, and interest on the Securities to the extent
lawful, all in accordance with the terms and subject to the limitations of the
Indenture as if GEC, GPC, NDC, APHC, CSALP and CMFC had been an original party
thereto; and (b) subject GEC, GPC, NDC, APHC, CSALP and CMFC to the provisions
(including the representations and warranties) of the Indenture as a Subsidiary
Guarantor.

                                   ARTICLE III

                                  MISCELLANEOUS

               SECTION 3.1 This Seventh Supplemental Indenture is a supplemental
indenture pursuant to Section 9.01 of the Indenture. Upon execution and delivery
of this Seventh Supplemental Indenture, the terms and conditions of this Seventh
Supplemental Indenture will be part of the terms and conditions of the Indenture
for any and all purposes, and all the terms and conditions of both shall be read
together as though they constitute one instrument, except that in case of
conflict, the provisions of this Seventh Supplemental Indenture will control.

               SECTION 3.2 Except as they have been modified in this Seventh
Supplemental Indenture, each and every term and provision of the Indenture shall
remain in full force and effect.

                                      - 2 -

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               SECTION 3.3 This Seventh Supplemental Indenture may be executed
in any number of counterparts, each of which when so executed and delivered
shall be an original, but such counterparts shall together constitute but one
and the same instrument.

               SECTION 3.4 This Seventh Supplemental Indenture shall be governed
by and construed in accordance with the laws of the State of New York without
giving effect to applicable principals of conflicts of law to the extent that
the application of the law of another jurisdiction would be required thereby.

                                   SIGNATURES

               IN WITNESS WHEREOF, the parties hereto have caused this Seventh
Supplemental Indenture to be duly executed as of the date first written above.

                                  COMPANY:

                                  CHESAPEAKE ENERGY CORPORATION

                                  By /s/ AUBREY K. MCCLENDON
                                    ------------------------------------------
                                    Aubrey K. McClendon, Chief Executive Officer

                                  GUARANTORS:

                                  THE AMES COMPANY, INC.
                                  CHESAPEAKE ACQUISITION CORPORATION
                                  CHESAPEAKE ROYALTY COMPANY
                                  NOMAC DRILLING CORPORATION
                                  CHESAPEAKE ENERGY LOUISIANA
                                    CORPORATION
                                  CHESAPEAKE CANADA CORPORATION
                                  CHESAPEAKE OPERATING, INC.
                                  CHESAPEAKE MOUNTAIN FRONT CORP.
                                  GOTHIC ENERGY CORPORATION
                                  GOTHIC PRODUCTION CORPORATION

                                  By /s/ AUBREY K. MCCLENDON
                                    -------------------------------------------
                                    Aubrey K. McClendon, Chief Executive Officer

                                      - 3 -

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                                  CHESAPEAKE EXPLORATION LIMITED
                                    PARTNERSHIP
                                  CHESAPEAKE LOUISIANA, L.P.
                                  CHESAPEAKE PANHANDLE LIMITED
                                    PARTNERSHIP
                                  CHESAPEAKE-STAGHORN ACQUISITION L.P.

                                  By: Chesapeake Operating, Inc., as general
                                      partner of each representative entity

                                      By  /s/ AUBREY K. MCCLENDON
                                        ---------------------------------------
                                        Aubrey K. McClendon,
                                        Chief Executive Officer

                                  ARKOMA PITTSBURG HOLDING CORPORATION

                                  By /s/ HENRY J. HOOD
                                    -------------------------------------------
                                    Henry J. Hood, President

                                  TRUSTEE:

                                  BANK OF NEW YORK, successor to United States
                                  Trust Company of New York, as Trustee

                                  By  /s/ LOUIS P. YOUNG
                                    -------------------------------------------
                                  Name:   Louis P. Young
                                       ----------------------------------------
                                  Title:  Authorized Signer
                                        ---------------------------------------

                                      - 4 -<PAGE>
                                                                   EXHIBIT 4.1.3

================================================================================

                          CHESAPEAKE ENERGY CORPORATION

                                       and

                     the Subsidiary Guarantors named herein

                    ----------------------------------------

                           7 7/8% SENIOR NOTES DUE 2004

                    ----------------------------------------

                                   ----------

                          EIGHTH SUPPLEMENTAL INDENTURE

                           DATED AS OF October 1, 2001

                                   ----------

                              THE BANK OF NEW YORK

                             as successor Trustee to

                     United States Trust Company of New York

                                   ----------

================================================================================

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         THIS EIGHTH SUPPLEMENTAL INDENTURE, dated as of October 1, 2001, is
among Chesapeake Energy Corporation, an Oklahoma corporation (the "Company"),
each of the parties identified under the caption "Subsidiary Guarantors" on the
signature page hereto (the "Subsidiary Guarantors") and The Bank of New York, as
successor to United States Trust Company of New York, as Trustee.

                                    RECITALS

         WHEREAS, the Company, the Subsidiary Guarantors a party thereto and the
Trustee entered into an Indenture, dated as of March 15, 1997, as supplemented
prior to the date hereof (the "Indenture"), pursuant to which the Company has
originally issued $150,000,000 in principal amount of 7 7/8% Senior Notes due
2004 (the "Notes"); and

         WHEREAS, Section 9.1(3) of the Indenture provides that the Company, the
Subsidiary Guarantors and the Trustee may amend or supplement the Indenture
without notice to or consent of any Holder to reflect the release of any
Subsidiary Guarantor, as provided for in the Indenture; and

         WHEREAS, the Company has taken all actions required to effect the
release, pursuant to Section 10.4 of the Indenture, of Chesapeake Canada
Corporation, an Alberta, Canada corporation ("Chesapeake Canada"), as a
Subsidiary Guarantor; and

         WHEREAS, all acts and things prescribed by the Indenture, by law and by
the charter and the bylaws (or comparable constituent documents) of the Company,
of the Subsidiary Guarantors and of the Trustee necessary to make this Eighth
Supplemental Indenture a valid instrument legally binding on the Company, the
Subsidiary Guarantors and the Trustee, in accordance with its terms, have been
duly done and performed;

         NOW, THEREFORE, to comply with the provisions of the Indenture and in
consideration of the above premises, the Company, the Subsidiary Guarantors and
the Trustee covenant and agree for the equal and proportionate benefit of the
respective Holders of the Notes as follows:

                                    ARTICLE 1

         Section 1.01. This Eighth Supplemental Indenture is supplemental to the
Indenture and does and shall be deemed to form a part of, and shall be construed
in connection with and as part of, the Indenture for any and all purposes.

         Section 1.02. This Eighth Supplemental Indenture shall become effective
immediately upon its execution and delivery by each of the Company, the
Subsidiary Guarantors and the Trustee.

                                    ARTICLE 2

         Chesapeake Canada shall for all purposes be released as a Subsidiary
Guarantor from all of its Guarantee and related obligations in the Indenture,
pursuant to Section 10.4 of the Indenture. The notation on the Securities
relating to the Guarantee shall be deemed to exclude the name of Chesapeake
Canada and the signature of an Officer of Chesapeake Canada on its behalf.

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                                    ARTICLE 3

         Section 3.01. Except as specifically modified herein, the Indenture and
the Notes are in all respects ratified and confirmed (mutatis mutandis) and
shall remain in full force and effect in accordance with their terms with all
capitalized terms used herein without definition having the same respective
meanings ascribed to them as in the Indenture.

         Section 3.02. Except as otherwise expressly provided herein, no duties,
responsibilities or liabilities are assumed, or shall be construed to be
assumed, by the Trustee by reason of this Eighth Supplemental Indenture. This
Eighth Supplemental Indenture is executed and accepted by the Trustee subject to
all the terms and conditions set forth in the Indenture with the same force and
effect as if those terms and conditions were repeated at length herein and made
applicable to the Trustee with respect hereto.

         Section 3.03. THE LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED
TO CONSTRUE AND ENFORCE THIS EIGHTH SUPPLEMENTAL INDENTURE.

         Section 3.04. The parties may sign any number of copies of this Eighth
Supplemental Indenture. Each signed copy shall be an original, but all of such
executed copies together shall represent the same agreement.

                          [NEXT PAGE IS SIGNATURE PAGE]

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         IN WITNESS WHEREOF, the parties hereto have caused this Eighth
Supplemental Indenture to be duly executed, all as of the date first written
above.

                                  COMPANY:

                                  CHESAPEAKE ENERGY CORPORATION

                                  By       /s/ AUBREY K. MCCLENDON
                                    -------------------------------------------
                                  Name:    Aubrey K. McClendon
                                       ----------------------------------------
                                  Title:   Chief Executive Officer
                                        ---------------------------------------

                                  SUBSIDIARY GUARANTORS:

                                  THE AMES COMPANY, INC.
                                  CHESAPEAKE ACQUISITION CORPORATION
                                  CHESAPEAKE ROYALTY COMPANY
                                  NOMAC DRILLING CORPORATION
                                  CHESAPEAKE ENERGY LOUISIANA
                                  CORPORATION
                                  CHESAPEAKE OPERATING, INC.
                                  CHESAPEAKE MOUNTAIN FRONT CORP.
                                  GOTHIC ENERGY CORPORATION
                                  GOTHIC PRODUCTION CORPORATION

                                  By       /s/ AUBREY K. MCCLENDON
                                    -------------------------------------------
                                  Name:    Aubrey K. McClendon
                                       ----------------------------------------
                                  Title:   Chief Executive Officer
                                        ---------------------------------------

                                  CHESAPEAKE EXPLORATION LIMITED
                                  PARTNERSHIP
                                  CHESAPEAKE LOUISIANA, L.P.
                                  CHESAPEAKE PANHANDLE LIMITED
                                  PARTNERSHIP
                                  CHESAPEAKE-STAGHORN ACQUISITION L.P.

                                    By: Chesapeake Operating, Inc. as general
                                        partner of each representative entity

                                    By   /s/ AUBREY K. MCCLENDON
                                      -----------------------------------------
                                    Name:    Aubrey K. McClendon
                                         --------------------------------------
                                    Title:   Chief Executive Officer
                                          -------------------------------------

<PAGE>

                                  ARKOMA PITTSBURG HOLDING
                                  CORPORATION

                                  By       /s/ HENRY J. HOOD
                                    -------------------------------------------
                                  Name:    Henry J. Hood
                                       ----------------------------------------
                                  Title:   President
                                        ---------------------------------------

                                  TRUSTEE:

                                  THE BANK OF NEW YORK, as successor to
                                  United States Trust Company of New York,
                                  as Trustee

                                  By       /s/ LOUIS P. YOUNG
                                    -------------------------------------------
                                  Name:    Louis P. Young
                                       ----------------------------------------
                                  Title:   Authorized Signer
                                        ---------------------------------------

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