EXHIBIT 3.1
                                                                     -----------

                               SECOND AMENDMENT TO

                         CERTIFICATE OF DESIGNATIONS OF

                SERIES A JUNIOR PARTICIPATING PREFERRED STOCK OF

                          CHESAPEAKE ENERGY CORPORATION

                    (Pursuant to Section 1032 of the General
                    Corporation Act of the State of Oklahoma)

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

            Chesapeake Energy Corporation,  a corporation organized and existing
under the General  Corporation Act of the State of Oklahoma  (hereinafter called
the "Company"),  hereby certifies that the following resolution was duly adopted
by the Board of  Directors  of the Company as  required  by Section  1032 of the
General Corporation Act of the State of Oklahoma  (hereinafter called the "Act")
and in accordance with Article IV of the Company's Certificate of Incorporation,
as amended (hereinafter called the "Certificate of Incorporation"), at a meeting
duly called and held on December 17, 2004:

            WHEREAS,  pursuant to the authority vested in the Board of Directors
of the Company in accordance with the Act and the Certificate of  Incorporation,
the Board of Directors is authorized by  resolution  duly adopted,  to designate
shares of preferred  stock to be issued,  in one or more series,  to provide for
the designation thereof of the powers,  designations,  preferences and relative,
participating,  optional or other  special  rights of the shares of such series,
and the qualifications, limitations or restrictions thereof;

            WHEREAS,  pursuant to the Certificate of Incorporation,  the Company
is  authorized to issue up to 20,000,000  shares of preferred  stock,  par value
$0.01 per share (the  "Preferred  Stock")  from time to time,  of which  350,000
shares  have been  designated  as the  Series A Junior  Participating  Preferred
Stock, 313,250 shares have been designated as the 4.125% Cumulative  Convertible
Preferred  Stock,  1,725,000  shares have been designated as the 5.0% Cumulative
Convertible  Preferred Stock,  4,600,000 shares have been designated as the 6.0%
Cumulative Convertible Preferred Stock and 2,997,800 shares have been designated
as the 6.75% Cumulative Convertible Preferred Stock; and

            WHEREAS,  on July 7, 1998,  the Board of  Directors  approved and on
July 17,  1998,  the  Company  filed with the  Oklahoma  Secretary  of State the
Certificate of  Designations  of Series A Junior  Participating  Preferred Stock
(the "Initial Certificate").

            WHEREAS,  on April 23, 2004 the Board of  Directors  approved and on
May 7, 2004,  the Company  filed with the Oklahoma  Secretary of State the First
Amendment  to  Certificate  of  Designations  of  Series A Junior  Participating
Preferred  Stock (the "First  Amendment")  and as a result of an increase in the
authorized  shares of the Company's common stock, par value $0.01 per share, the
Board of  Directors  desires to increase the number of shares of Series A Junior
Participating  Preferred Stock designated by the Initial Certificate and amended
by the First Amendment.

            NOW THEREFORE BE IT RESOLVED,  that pursuant to the authority vested
in the Board of Directors of the Company in  accordance  with the  provisions of
the Act and the Certificate of Incorporation, the Initial Certificate as amended
by the First Amendment is amended as follows:

1.  Increase in Shares.  In order to  increase  the number of shares of Series A
Junior  Participating  Preferred Stock,  Section 1 of the Initial Certificate as
amended by the First  Amendment is deleted in its entirety and the  following is
substituted therefore:

            Section 1.  Designation and Amount.  The shares of such series shall
            be designated  as "Series A Junior  Participating  Preferred  Stock"
            (the   "Series  A  Preferred   Stock")  and  the  number  of  shares
            constituting  the Series A Preferred  Stock  shall be 500,000.  Such
            number of shares may be increased or decreased by  resolution of the
            Board of  Directors;  provided,  that no decrease  shall  reduce the
            number of shares of Series A  Preferred  Stock to a number less than
            the  number of shares  then  outstanding  plus the  number of shares
            reserved for  issuance  upon the  exercise of  outstanding  options,
            rights  or  warrants  or  upon  the  conversion  of any  outstanding
            securities issued by the Company convertible into Series A Preferred
            Stock.



2. Full Force and Effect. Except as specifically amended herein, all other terms
and provisions of the Initial Certificate remain in full force and effect.

            IN  WITNESS  WHEREOF,   this  Second  Amendment  to  Certificate  of
Designations  is executed on behalf of the Company by its  Chairman of the Board
and Chief  Executive  Officer  and  attested by its  Secretary  this 20th day of
December, 2004.


                                       /s/ Aubrey K. McClendon
                                       --------------------------------
                                       Aubrey K. McClendon
                                       Chairman of the Board and
                                        Chief Executive Officer


Attest: /s/ Jennifer M. Grigsby
        ------------------------------
         Jennifer M. Grigsby
         Corporate Secretary


                                       2