SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549



                                    FORM 8-K



                             Current Report Pursuant
                          to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



    Date of report (Date of earliest event reported)    August 24, 1998
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                               UNOCAL CORPORATION
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             (Exact name of registrant as specified in its charter)



                                    Delaware
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                 (State or Other Jurisdiction of Incorporation)



    1-8483                                   95-3825062
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(Commission File Number)                (I.R.S. Employer Identification No.)



2141 Rosecrans Avenue, Suite 4000, El Segundo, California         90245
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(Address of Principal Executive Offices)                       (Zip Code)



                                 (310) 726-7600
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              (Registrant's Telephone Number, Including Area Code)



Item 5.           Other Events.











On August 24, 1998, Unocal  Corporation  announced the test of a second interval
in the West Seno #2 deepwater  discovery  well  offshore  Indonesia  flowed at a
daily rate of 10,069  barrels of 39-degree API gravity oil and 9.5 million cubic
feet of natural gas.

This drillstem test (DST) was from a true vertical depth subsea (TVDS)  interval
between 8,007 feet and 8,064 feet on a 1-1/4-inch choke. Flowing tubing pressure
was 830 pounds per square inch.

On August 17, Unocal announced a successful DST on a deeper interval in the West
Seno #2 well.  Mechanical  equipment problems  prevented  conducting a high rate
test on that interval,  but yielded important reservoir  information.  In total,
the West Seno #2 well  encountered  172 feet of vertical  hydrocarbon pay in two
zones between 7,300 feet and 8,600 feet TVDS.  The well is located in 2,800 feet
of water.  Flow tests and wireline logging  indicate  porosity of 30 percent and
excellent permeability in the formations.

The West Seno #2 well is Unocal Indonesia's second deepwater  discovery offshore
East  Kalimantan in the Kutei Basin.  The extent and  commerciality  of the West
Seno discovery will be determined following additional appraisal drilling.

The West  Seno #2 well is  located  on the  Makassar  Strait  production-sharing
contract (PSC) area. Unocal Indonesia Company is operator of the Makassar Strait
PSC and has a 50-percent  working  interest.  Mobil  Makassar,  Inc.,  holds the
remaining  50 percent.  Under the terms of the PSC,  Unocal,  as  contractor  to
Pertamina, the Indonesian national oil company, is entitled to varying shares of
the oil and gas produced from commercial discoveries.

Forward-looking  statements about future exploration and development  activities
and  projected  results  set forth  above are  based on  assumptions  concerning
geology,  regulatory actions, economic, market conditions,  operational concerns
and other considerations. Actual results could differ materially.



Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, thereunto duly authorized.


                                         UNOCAL CORPORATION
                                            (Registrant)


Date:  August 26, 1998                   By:  /s/  JOE D. CECIL
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                                              Joe D. Cecil
                                              Vice President and Comptroller

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