EXHIBIT 99.1
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                     CHESAPEAKE ENERGY CORPORATION ANNOUNCES
                  MANDATORY CONVERSION OF 6.75% PREFERRED STOCK

OKLAHOMA  CITY,  OKLAHOMA,  NOVEMBER  19, 2004 - Chesapeake  Energy  Corporation
(NYSE:CHK)  today  announced that it will convert all of its  outstanding  6.75%
Cumulative  Convertible  Preferred  Stock,  par  value  $0.01  per  share,  into
Chesapeake  Energy  Corporation  Common  Stock,  par value  $0.01 per share,  on
November 22, 2004 (the "Conversion Date").

On the  Conversion  Date,  6.4935  shares of common  stock  will be issued  upon
conversion of each share of 6.75% preferred stock and dividends on the preferred
stock will cease to accrue.  Cash will be paid in lieu of  fractional  shares of
common  stock.  No payment or  adjustment  will be made upon  conversion  of the
preferred stock for accrued dividends with respect to the preferred stock or for
dividends  with respect to the common stock  issued upon  conversion.  There are
currently 2,714,200 shares of preferred stock outstanding.

From and after November 22, 2004, the preferred  stock not previously  converted
will be deemed to be no longer  outstanding  and all rights of the holders  with
respect to such preferred stock will terminate,  except the right to receive the
whole shares of common stock  issuable upon  conversion  and cash in lieu of any
fractional shares, as described above.

A Notice of Conversion will be mailed to shareholders of record of the preferred
stock as of the close of business on November 17, 2004. The Conversion  Agent is
UMB Bank, N.A., 928 Grand Boulevard,  13th Floor, Kansas City, Missouri,  64106,
telephone (816) 860-7411.


Chesapeake Energy Corporation is one of the six largest independent producers of
natural gas in the U.S. Headquartered in Oklahoma City, the company's operations
are focused on exploratory  and  developmental  drilling and producing  property
acquisitions in the Mid-Continent,  Permian Basin, South Texas, Texas Gulf Coast
and Ark-La-Tex  regions of the United States.  The company's Internet address is
WWW.CHKENERGY.COM.