Exhibit 99.1

                   CIMAREX ENERGY PROVIDES OPERATIONAL UPDATE

    DENVER, Sept. 27  -- Cimarex Energy Co. (NYSE: XEC)
today announced that approximately 125 million cubic feet per day of its
natural gas equivalent production (MMcfe/d) remains shut-in as a result of
hurricane activity in the Gulf of Mexico and nearby coastal areas.

    Production curtailments in anticipation of Hurricane Rita began Wednesday,
September 21 and total company-wide net volumes shut in reached a maximum of 145
MMcfe/d over the weekend. Included in the peak amount of curtailments was 20
MMcfe/d of Permian Basin production that was turned offline because third-party
gas processing facilities were shut down.

    Of total remaining shut-in volumes, approximately 65 MMcfe/d is from Gulf of
Mexico fields and 60 MMcfe/d is from wells located in Vermilion Parish,
Louisiana, Liberty County, Texas and other areas along the Texas Gulf Coast.
Included in the total amount of shut-in offshore volumes is 14 MMcfe/d that was
initially curtailed on August 28 because of Hurricane Katrina.

    Preliminary inspections of operated facilities and reports from other
operators indicate little to no apparent damage to affected production
facilities. As such, current general expectations are that the bulk of the
Hurricane Rita related curtailments should be back online within two weeks.
However, because of extensive flooding and the requisite start-up of downstream
trucking operations, gas transportation pipelines, gas processing plants and
offshore production facilities managed by others, the exact timing of the
resumption of output is still being assessed and may change.

    Depending on the receipt of more definitive information from industry
partners, downstream facility operators, affected regulatory agencies, and
select oil and gas purchasers, Cimarex currently plans to update its overall
2005 production outlook in conjunction with its third-quarter 2005 operations
update and earnings release.

    The company has also been informed by one of its partners that two offshore
jackup rigs drilling wells on blocks in which Cimarex had working interests are
no longer at their pre-storm locations.

    About Cimarex Energy
    Denver-based Cimarex Energy Co. is an independent oil and gas exploration
and production company with principal operations in the Mid-Continent, Gulf
Coast, Permian Basin of West Texas and New Mexico and Gulf of Mexico areas of
the U.S.

    This communication contains statements that constitute forward-looking
statements within the meaning of the Private Securities Litigation Reform Act of
1995. These statements are based on current expectations and beliefs and are
subject to a number of risks, uncertainties and assumptions that could cause
actual results to differ materially from those described in the forward-looking
statements. Risks, uncertainties and assumptions include 1) the possibility that
problems may arise in successfully integrating the Magnum Hunter acquisition; 2)
the possibility that the acquisition may involve unexpected costs; 3) the
possibility that the industry may be subject to future regulatory or legislative
actions; 4) the volatility in commodity prices for oil and gas; 5) the presence
or recoverability of estimated reserves; 6) the ability to replace reserves; 7)
environmental risks; 8) drilling and operating risks; 9) exploration and
development risks; 10) competition; 11) the ability of management to execute its
plans to meet its goals and other risks that are described in SEC reports filed
by Cimarex. Because forward-looking statements involve risks and uncertainties,
actual results and events may differ materially from results and events
currently expected by Cimarex. Cimarex assume no obligation and expressly
disclaim any duty to update the information contained herein except as required
by law.