Exhibit 20

FOR IMMEDIATE RELEASE  CONTACT: Guy T. Marcus     Edward P. Delson     
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June 10, 1997                   VP-Inv. Rel.      Sr. VP-CFO           
                                Halliburton       NUMAR                
                                (214) 978-2691    (610) 251-0116         

                   HALLIBURTON TO ACQUIRE NUMAR CORPORATION
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     DALLAS, Texas -- Halliburton Company (NYSE:HAL) and NUMAR Corporation
(NASDAQ:NUMR) today jointly announced that they have signed a definitive
agreement providing for the acquisition of NUMAR by Halliburton in a stock-for-
stock transaction valued at about $360 million, or approximately $39.62 per
NUMAR share, based on Halliburton's closing share price on June 9, 1997.

     Under terms of the agreement, Halliburton will issue 0.4832 of a share of
its common stock for each outstanding share of NUMAR common stock (or 0.9664 of
a share presuming the acquisition closes following Halliburton's previously
announced 2-for-1 common stock split for shareholders of record at the close of
business on the June 26, 1997 record date).  Also, options and warrants of NUMAR
will be converted into Halliburton common stock securities based upon this
exchange ratio.  The acquisition will result in the issuance of approximately
4.4 million shares of Halliburton common stock (approximately 8.8 million shares
following the 2-for-1 stock split).  Approximately 130.9 million shares of
Halliburton common stock will be outstanding following completion of the
acquisition (261.8 million shares following the stock split).

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     The proposed merger has received unanimous approval from the boards of
directors of each company, but is subject to the approval of NUMAR's
stockholders and Hart-Scott-Rodino antitrust clearance.  For accounting
purposes, the merger will be structured as a pooling of interests and for
federal income tax purposes as a tax-free exchange to NUMAR shareholders.
NUMAR's directors and other affiliates representing over 25 percent of NUMAR's
shares have agreed to vote in favor of the proposed transaction.  The companies
anticipate completion of the acquisition during the 1997 third quarter.

     Dick Cheney, Halliburton Company's chairman of the board and chief
executive officer, said, "The acquisition of NUMAR is a strategic move
Halliburton is making to strengthen our position in the $3.2 billion formation
evaluation market. NUMAR has established itself as an industry leader with its
proprietary MRIL(R) technology which is fundamentally changing the future
direction of the marketplace.  Halliburton can help NUMAR to accelerate
development, delivery and application of the MRIL technology to benefit
customers by utilizing Halliburton's worldwide infrastructure.  The technology
is currently being applied to a small percentage of wells drilled worldwide, but
future growth opportunities are significant."

     NUMAR designs, manufactures and markets a patented proprietary well logging
device, the Magnetic Resonance Imaging Logging ("MRIL") tool, which

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Halliburton Company                   3

utilizes magnetic resonance imaging ("MRI") technology, to evaluate subsurface
rock formations in newly-drilled oil and gas wells.  The MRIL tool measures
directly in real time at the wellsite the formation porosity, proportion of
fluid in the formation that is free to flow, fluid viscosity and type of
hydrocarbons in the pore space, and derived formation permeability.
Furthermore, these measurements are accomplished without the use of radioactive
sources, which are present in the traditional density and neutron logging tools.

     Halliburton believes the MRIL technology represents a major breakthrough in
wireline logging and that the acquisition of NUMAR will strengthen its position
in logging as the MRIL technology is deployed throughout the global Halliburton
organization.  Over the last two years, Halliburton has been a licensee of NUMAR
and, as a result, has had the opportunity to gain insight into MRIL technology,
including testing the reliability and performance of NUMAR's MRIL tools and to
verify the level of technological acceptance among a broad cross-section of
major customers around the world.

     While modestly dilutive to near-term earnings per share, Halliburton
believes that the transaction will not be dilutive to earnings per share for
1998 as the deployment of further enhancements increases customers acceptance of
MRIL technology.

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     NUMAR will operate as a wholly-owned subsidiary of Halliburton Company, and
part of Halliburton's Energy Services business segment.  Following the merger,
NUMAR's management team will remain in place with Dr. Melvin Miller continuing
as president.

     Miller said, "NUMAR is highly ambitious in its goal to provide the source
of real-time data with which oil and gas companies can better determine the
presence of hydrocarbons, the characteristics of rock formations and whether
commercial quantities of oil and gas can be recovered.  We are delighted to join
forces with Halliburton to accelerate and expand the scope and range of MRIL
technology throughout the world."

     NUMAR has distribution agreements with several service companies for the
use of MRIL technology.  The company will continue to honor these agreements.

     NUMAR Corporation was founded in 1983 and maintains its headquarters in
Malvern, Pennsylvania.  The company has about 140 employees and provides the
MRIL service to over 200 oil and gas company customers worldwide.

     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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