FOR IMMEDIATE RELEASE             Contact  Guy T. Marcus      Edward P. Delson
July 14, 1997                              VP-Inv. Rel.       Sr. VP-CFO
                                           Halliburton        NUMAR
                                           (214) 978-2691     (610) 251-0116


                HART-SCOTT-RODINO ANTITRUST CLEARANCE FOR NUMAR

DALLAS,   Texas  --  Halliburton   Company   (NYSE:HAL)  and  NUMAR  Corporation
(NASDAQ:NUMR)   said  today  that  the  waiting  period  for   Hart-Scott-Rodino
anti-trust  review of  Halliburton's  planned  acquisition of NUMAR  Corporation
lapsed  as of July  13,  1997.  Both  companies  stated  that  they  expect  the
acquisition  to close in the 1997 third  quarter,  following  completion  of SEC
review of  NUMAR's  proxy  statement  for a  special  shareholders  meeting  and
assuming approval of the acquisition by NUMAR shareholders at such meeting.  The
date of such shareholders  meeting has not been set, but will take place as soon
as practicable.

     NUMAR is the world  leader and  pioneer  in the  design,  manufacture,  and
marketing of  commercial  applications  of magnetic  resonance  imaging  ("MRI")
technology  for  oil and  gas  exploration  and  development.  NUMAR's  patented
proprietary  device,  the MRIL( tool, applies MRI technology to fluid estimation
and formation evaluation in newly-drilled oil and gas wells to improve estimates
of reserve and well productivity.

                                     -more-

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     Halliburton  Company  is one  of the  world's  largest  diversified  energy
services, engineering, maintenance, and construction companies. Founded in 1919,
Halliburton  provides a broad range of energy services and products,  industrial
and marine engineering and construction services.

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