UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
 
                             Washington, D.C. 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 13, 1998
 
                                USX Corporation
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             (Exact name of registrant as specified in its charter)
 

                                  
        Delaware             1-5153        25-0996816
 -----------------------  ------------  -----------------
    (State or other       (Commission     (IRS Employer
    jurisdiction of       File Number)   Identification
     incorporation)                           No.)
 
   600 Grant Street, Pittsburgh, PA        15219-4776
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   (Address of principal executive         (zip code)
               offices)

 
                                 (412) 433-1121
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              (Registrant's telephone number, including area code)

ITEM 5. OTHER EVENTS
 
    On May 29, 1998, USX Corporation announced that its Marathon Oil Company
("Marathon") subsidiary had entered into an agreement to acquire Tarragon Oil
and Gas Limited ("Tarragon"), a Canadian corporation. A special meeting of
Tarragon securityholders is scheduled to be held on August 11, 1998, to request
securityholder approval of the proposed transaction whereby a Canadian
subsidiary of Marathon would acquire all of the issued and outstanding
securities of Tarragon. The board of directors of Tarragon has recommended that
securityholders vote to approve the transaction. The transaction is also subject
to approval by the Ontario Court (General Division), Ontario, Canada.
 
    On July 13, 1998, Tarragon mailed its Notice of Special Meeting, Notice of
Motion and Information Circular ("Tarragon Information Circular") relating to
the special meeting of securityholders. Financial information related to the
acquisition of Tarragon by Marathon is not required under the materiality
requirements of the applicable sections of the Securities Exchange Act of 1934
or the Securities Act of 1933. However, unaudited pro forma financial statements
of the USX-Marathon Group, USX Corporation and Tarragon were included as
Appendix M in the Tarragon Information Circular. A copy of Appendix M is filed
herewith as an exhibit for the benefit of U.S. investors and shareholders of USX
Corporation.
 
ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS
 
    (c) Exhibits
 
    99. Unaudited Pro Forma Financial Statements excerpted from the Tarragon
       Information Circular
 
                                   SIGNATURE
 
    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 hereunto duly authorized.
 

        
USX CORPORATION
 
By:        /s/ Kenneth L. Matheny
           -------------------------------------
           Kenneth L. Matheny
           Vice President and Comptroller
 
Dated:  July 16, 1998