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                                                                    EXHIBIT 99.1



                                                                   PRESS RELEASE


                                       Contact:                 T. Scott O'Keefe
                                                        Sr. Vice President & CFO
                                                                  (281) 243-3000
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                                NYSE SYMBOL: MRL

         MARINE DRILLING COMPANIES, INC. DISCLOSES WELL-CONTROL INCIDENT

SUGAR LAND, TEXAS, JULY 13, 2001--Marine Drilling Companies, Inc. (NYSE: MRL)
today reported that its MARINE 4 jack-up rig had a well control incident at
Brazos Block #417 at approximately 4:15 a.m. CDT this morning. The rig has been
evacuated. At present 39 of the 40 people onboard the rig have been accounted
for, and the family of the missing man has been notified. The well control
incident occurred this morning while drilling a natural gas well for Applied
Drilling Technology, Inc. a subsidiary of Global Marine Inc. (NYSE: GLM). To our
knowledge no ignition of escaping gas has occurred, and we are unable to board
the rig to assess any damage to the rig at this time. The Company's Emergency
Management Team has been deployed, the U. S. Coast Guard and Minerals Management
Services have been notified and steps are presently underway with well control
specialists to gain control of the well.

Marine Drilling Companies, Inc. is an offshore drilling contractor with a fleet
of 17 offshore drilling rigs and one jack-up rig currently configured as an
accommodation unit. The drilling rig fleet, operating in the U.S. Gulf of Mexico
and selected international markets, consists of 15 jackups and two deep-water
semi-submersibles.

         This press release includes certain statements that may be deemed to be
"forward-looking statements" within the meaning of Section 27A of the Securities
Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934,
as amended. All statements, other than statements of historical facts, included
in this press release that address activities or events the company believes
will or may occur in the future are forward-looking statements. Such statements
are subject to a number of uncertainties that are discussed in the company's
most recent Forms 10-K and 10-Q. Investors are cautioned that actual results may
differ materially from those projected in the forward-looking statements.

          For online information about Marine Drilling Companies, Inc.

                              visit www.mardril.com

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