Exhibit 4.5

 
                             DECLARATION OF TRUST


          DECLARATION OF TRUST, dated as of March 13, 1997, between USX
Corporation, a Delaware corporation, as Sponsor, The Bank of New York, The Bank
of New York (Delaware), a Delaware banking corporation, A.G. Adkins, P.J. Kuntz,
and M.K. Stewart as Trustees.  The Sponsor and the Trustees hereby agree as
follows:

          1.  The trust created hereby (the "Trust") shall be known as "USX
Capital Trust I", in which name the Trustees, or the Sponsor to the extent
provided herein, may conduct the business of the Trust, make and execute
contracts, and sue and be sued.

          2.  The Sponsor hereby assigns, transfers, conveys and sets over to
the Trustees the sum of $10.  The Trustees hereby acknowledge receipt of such
amount in trust from the Sponsor, which amount shall constitute the initial
trust estate.  The Trustees hereby declare that they will hold the trust estate
in trust for the Sponsor.  It is the intention of the parties hereto that the
Trust created hereby constitute a business trust under Chapter 38 of Title 12 of
the Delaware Code, 12 Del. C. Section 3801 et seq. (the "Business Trust Act"),
and that this document constitute the governing instrument of the Trust.  The
Trustees are hereby authorized and directed to execute and file a certificate of
trust with the Delaware Secretary of State in the form attached hereto.

          3.  The Sponsor and the Trustees will enter into an amended and
restated Declaration of Trust, satisfactory to each such party and substantially
in the form to be included as Exhibit 4.6 to the Registration Statement referred
to below, to provide for the contemplated operation of the Trust created hereby
and the issuance of the Trust Convertible Preferred Securities and Trust Common
Securities referred to therein.  Prior to the execution and delivery of such
amended and restated Declaration of Trust, the Trustees shall not have any duty
or obligation hereunder or with respect to the trust estate, except as otherwise
required by applicable law or as may be necessary to obtain prior to such
execution and delivery any licenses, consents or approvals required by
applicable law or otherwise.

          4.  The Sponsor and the Trustees hereby authorize and direct the
Sponsor, in each case on behalf of the Trust as the sponsor of the Trust, (i) to
prepare for filing with the Securities and Exchange Commission (the
"Commission") (a) a Registration Statement on Form S-4 and any pre-effective or
post-effective amendments to such Registration Statement (the "Registration
Statement"), relating to the registration under the Securities Act of 1933, as
amended, of the Trust Convertible Preferred Securities of the Trust, and (b) a
Registration Statement on Form 8-A or other form issued or permitted by the
Commission, including all pre-effective and post-effective amendments thereto
(the "1934 Act Registration Statement"), relating to the registration of the
Trust Convertible Preferred Securities under the Securities Exchange Act of
1934, as amended; (ii) to execute and file with the New York Stock Exchange, the
American Stock Exchange or such other national securities exchange or the Nasdaq
Stock Market as the Sponsor shall determine, a listing or other similar
application and all other applications, statements, certificates, agreements and
other instruments as shall be necessary or desirable to cause the Trust
Convertible Preferred Securities to be listed or approved for quotation on the
New York Stock Exchange, the American Stock Exchange or


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such other national securities exchange or the Nasdaq Stock Market; (iii) to
execute and file such applications, reports, surety bonds, irrevocable consents,
appointments of attorneys for service of process and other papers, documents and
agreements as shall be necessary or desirable to register the Trust Convertible
Preferred Securities under the securities or "Blue Sky" laws of such
jurisdictions as the Sponsor, on behalf of the Trust, may deem necessary or
desirable and (iv) to negotiate and execute a Dealer Manager Agreement among the
Trust, the Sponsor, Goldman, Sachs & Co. and Merrill Lynch & Co., and the other
parties thereto, relating to the Exchange Offer (as defined in the Registration
Statement), substantially in the form to be included as Exhibit 1.1 to the
Registration Statement.

          It is hereby acknowledged and agreed that in connection with any
document referred to in clauses (i) - (iii) above, (A) any Regular Trustee (or
his attorneys-in-fact and agents or the Sponsor as permitted herein) is
authorized on behalf of the Trust to execute such document on behalf of the
Trust, provided that the Registration Statement shall be signed by all of the
Regular Trustees, and (B) The Bank of New York and The Bank of New York
(Delaware), in their capacities as Trustees of the Trust shall not be required
to join in any such filing or execute on behalf of the Trust any such document
unless required by the rules and regulations of the Commission, the New York
Stock Exchange (or other national securities exchange or the Nasdaq Stock
Market) or state securities or "Blue Sky" laws, and in such case only to the
extent so required.  In connection with all of the foregoing, each Regular
Trustee, solely in his capacity as Trustee of the Trust, hereby constitutes and
appoints William F. Schwind, Jr., Kenneth J. Orlowski, and Richard Molina, and
each of them, as his true and lawful attorneys-in-fact and agents, with full
power of substitution and resubstitution, for such Regular Trustee or in such
Regular Trustee's name, place and stead, in any and all capacities, to sign the
Registration Statement and any and all amendments (including post-effective
amendments) thereto, and to file the same, with all exhibits thereto, and other
documents in connection therewith, with the Commission, granting unto said
attorneys-in-fact and agents, or any of them, full power and authority to do and
perform each and every act and thing requisite and necessary to be done in
connection therewith, as fully to all intents and purposes as such Regular
Trustee might or could do in person, hereby ratifying and confirming all that
said attorney-in-fact and agent, or his substitute or substitutes, shall do or
cause to be done by virtue hereof.

          5.  This Declaration of Trust may be executed in counterparts.

          6.  The number of Trustees initially shall be five (5) and thereafter
the number of Trustees shall be such number as shall be fixed from time to time
by a written instrument signed by the Sponsor which may increase or decrease the
number of Trustees; provided that to the extent required by the Business Trust
Act, one Trustee shall either be a natural person who is a resident of the State
of Delaware or, if not a natural person, an entity which has its principal place
of business in the State of Delaware.  Subject to the foregoing, the Sponsor is
entitled to appoint or remove without cause any Trustee at any time.  The
Trustees may resign upon thirty days prior notice to the Sponsor.

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          IN WITNESS WHEREOF, the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.

                              USX CORPORATION, as Sponsor


                                   /s/ G. R. Haggerty
                              By:___________________________________
                                 Name:  G. R. Haggerty
                                 Title: Vice President and Treasurer


                                /s/ A. G. Adkins
                              ______________________________________
                              A.G. Adkins, as Trustee



                                /s/ P. J. Kuntz
                              ______________________________________
                              P.J. Kuntz, as Trustee



                                /s/ M. K. Stewart
                              ______________________________________
                              M.K. Stewart, as Trustee



                              THE BANK OF NEW YORK, as Trustee

                                   /s/ Mary La Gumina
                              By___________________________________
                                 Name:  Mary La Gumina
                                 Title: Assistant Vice President


                              THE BANK OF NEW YORK (DELAWARE),
                              as Trustee



                                   /s/ Frederick Clark
                              By___________________________________
                                 Name:  Frederick Clark
                                 Title: Authorized Signatory