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)        April 15, 1999
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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.


Unocal  Corporation's  Unocal Canada  Resources  (Unocal Canada)  subsidiary has
signed a definitive  agreement to invest up to C$265 million (US$175 million) to
acquire up to 46 percent of Calgary-based Northrock Resources Ltd (Northrock).

Unocal's Chairman and Chief Executive Officer Roger C. Beach said, "The addition
of the Northrock interest is a key element of our North American gas strategy."

Under the  agreement,  Unocal Canada  proposes to make a partial tender offer to
Northrock's  shareholders  which,  if successful,  would result in Unocal Canada
acquiring  approximately 10 million shares of Northrock common stock at C$14 per
share, representing approximately 32 percent of all outstanding shares.

Northrock's  board has  agreed  to  support  Unocal  Canada's  tender  offer and
recommend acceptance by Northrock's shareholders.  The tender offer will include
a condition  that Unocal Canada obtain at least 6.9 million  shares of Northrock
common stock.

If Unocal's tender offer is successful, Unocal Canada will acquire approximately
7.6 million  additional shares of Northrock common stock at C$16 per share under
a private placement, increasing Unocal Canada's interest in Northrock to as much
as 46 percent.

As part of the  agreement,  Northrock  has the right,  until Dec. 31,  1999,  to
require that Unocal purchase additional common shares from Northrock's  treasury
at a price of C$15 per share, up to a maximum ownership level to 49.9 percent.

Unocal  Canada's  obligations  under the  agreement  are  subject to  regulatory
approvals  and  certain  other  conditions.  The  transaction  is expected to be
completed by mid-May.

Northrock has also agreed to pay Unocal Canada a  non-completion  fee in certain
circumstances in the event that the proposed  acquisition of Northrock shares by
Unocal Canada is unsuccessful.

In March 1999,  Northrock reported current average daily gross production of 160
million  cubic  feet of gas and  11,000  barrels  of crude oil and  natural  gas
liquids.  Unocal estimates Northrock had net proved reserves of approximately 35
million  barrels of crude oil and liquids  and 363 billion  cubic feet of gas at
March 31, 1999.



Forward-looking   statements  regarding  exploration   activities  and  resource
potential  in  this  filing  are  based  on   assumptions   concerning   market,
competitive,  regulatory,  environmental,  operational and other considerations.
Actual  results  could  differ  materially  as a result of factors  discussed in
Unocal's  1998  Form  10-K  report  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:  April 15, 1999                        By:   /s/ JOE D. CECIL             
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                                                  Joe D. Cecil
                         Vice President and Comptroller