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)        July 23, 2003
                                                        ------------------------



                               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.


Ganal Discovery
----------------

       Unocal Corporation (the "Company") announced that its Unocal Ganal, Ltd.
("Unocal Ganal"), subsidiary has made a significant gas-condensate and oil
discovery on the deepwater Gehem prospect in the Ganal production-sharing
contract area, 3.5 miles south of the Ranggas field offshore East Kalimantan,
Indonesia.

       Gehem-1 is the first of a series of exploration wells that are designed
to test the prospectivity of deeper, previously untested intervals underlying
previous deepwater discoveries offshore East Kalimantan. The Gehem-1 well
encountered 617 feet of net gas and gas-condensate pay and 18 feet of net oil
pay. The well was drilled in 5,981 feet of water to a total vertical depth of
15,241 feet. More than 400 feet of the net pay was in a stratigraphic interval
that had not been penetrated during drilling in the nearby Ranggas field. The
Company said the Gehem structure covers nearly 8,000 acres and has the potential
for significant oil pay in several zones downdip of the Gehem-1 well and in
deeper intervals, which will be tested in subsequent appraisal wells. Well
designs for follow-up appraisals on the Gehem prospect will permit tests that
are deeper than the initial well, which encountered only moderate pressures even
at total depth.

       Gehem-1 drilling results indicate that there is a thick, high-quality
hydrocarbon-bearing reservoir at previously untested depths. The well results
increase the prospectivity of the deep oil prospects that are already on the
Company's drilling schedule for 2003 and expand the Company's portfolio of leads
and prospects focused on deeper oil and gas. Gehem by itself has a number of
characteristics that favor early development. The size of the potential Gehem
resource, reservoir quality, potential high condensate yields and location
relative to the Bontang liquefied natural gas plant, position Gehem to be a
low-cost gas supplier to the plant. The reservoir has the potential for flowing
in excess of 100 million cubic feet of gas per day and 5,000 barrels of
condensate per day per well.

       The results of the Gehem-1 well indicate possibly significant oil and
condensate accumulations in the deeper untested trend underlying the existing
Gada, Gula, and Ranggas discoveries. In addition, armed with the information
gathered from the Gehem-1 well, the Company has already developed a number of
new leads and prospects, including Golok (structure directly north of the Gula
discovery), Geliga (structure south of the Gada discovery), and Rajalaut
(adjacent to Ranggas).

Unocal Ganal is operator of the Ganal PSC area and holds an 80-percent working
interest.

Ranggas Appraisal Drilling
--------------------------

       The Company also announced that its Unocal Rapak, Ltd. ("Unocal Rapak"),
subsidiary has successfully completed drilling the Ranggas Selatan-1 appraisal
well, extending the Ranggas field to the south on the Rapak production-sharing
contract area. The Selatan-1 well was drilled to a true vertical depth of 10,243
feet, and penetrated 187 feet of net oil pay and 258 feet of net gas pay in
several zones of high quality reservoir rock. The well was not planned to
penetrate the deep reservoir that was encountered in the Gehem-1 well. The
Selatan-1 well was drilled 1 mile south of the Ranggas-1 discovery well and 5.7
miles north of the Gehem-1 well.

       The Company said it is conducting conceptual engineering studies for the
possible development of the Ranggas field. Extending the Ranggas oil and gas
accumulations to the south is an important and positive appraisal step for the
field. While the Company is still planning to have the Ranggas project ready for
government approval by early next year, the Gehem-1 results have implications
for appraising the deeper oil potential at Ranggas and optimizing the
development. The Company plans to move Ranggas along while assessing the deep
potential and options for co-development with Gehem.

Unocal Rapak is operator of the Rapak PSC area and holds and 80-percent working
interest.
                                      -1-


This filing contains certain forward-looking statements about Unocal's future
development plans and production estimates. These statements are not guarantees
of future performance. The statements are based upon Unocal's current
expectations and beliefs and are subject to a number of known and unknown risks
and uncertainties that could cause actual results to differ materially from
those described in the forward looking statements. Actual results could differ
materially as a result of factors discussed in Unocal's 2002 Annual Report on
Form 10-K and subsequent reports filed with the Securities and Exchange
Commission.

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:  July 24, 2003                              By:  /s/ JOE D. CECIL
      ------------------                         -------------------------------
                                                 Joe D. Cecil
                                                 Vice President and Comptroller

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