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                                                                    EXHIBIT 4-2


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                         FIRST SUPPLEMENTAL INDENTURE
                                      
                           Dated as of June 4, 1997
                                      
                                   between
                                      
                            MCN ENERGY GROUP INC.
                                      
                                  AS ISSUER
                                      
                                     and
                                      
                                   NBD BANK
                                      
                                  AS TRUSTEE
                                      
                         Supplementing the Indenture
                         Date as of September 1, 1994

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        FIRST SUPPLEMENTAL INDENTURE, dated as of June 4, 1997 (the "First
Supplemental Indenture"), between MCN Energy Group Inc. (formerly MCN
Corporation), a corporation duly organized and existing under the laws of the
State of Michigan, having its principal office at 500 Griswold Street, Detroit,
Michigan 48226 (the "Company"), and NBD Bank, a Michigan banking corporation
(formerly NBD Bank, N.A.), as trustee (the "Trustee").

        WHEREAS, the Company executed and delivered the Senior Debt Securities
Indenture dated as of September 1, 1994 (the "Indenture"), to the Trustee to
provide for the future issuance of the Company's unsecured debentures, notes or
other evidence of indebtedness (the "Securities"), to be issued from time to
time in one or more series as might be determined by the Company under the
Indenture;

        WHEREAS, pursuant to the terms of the Indenture, the Company desires to
supplement and amend the Indenture, including amending and restating certain
provisions relating to an Event of Default as set forth in Article Five,
Section 501(4) of the Indenture and certain definitions as set forth in Article 
One, Section 101 of the Indenture;

        WHEREAS, the Board of Directors of the Company has authorized the
Company to enter into this First Supplemental Indenture with the Trustee;
    
        WHEREAS, all things necessary to make this First Supplemental Indenture
a valid agreement of the Company and the Trustee in accordance with its terms
and a valid amendment and supplement to the Indenture, have been done.

        NOW, THEREFORE, for and in consideration of the premises and mutual
covenants herein contained, the Company and the Trustee agree as follows for
the purposes of setting forth the terms, provisions and conditions of the
desired amendments to Article Five, Section 501(4) of the Indenture and Article
One, Section 101 of the Indenture:

                                  ARTICLE I
                                 DEFINITIONS
                                      
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SECTION 1.1.    Definition of Terms.
           
          Unless the context otherwise requires:

          (a)   a term defined in the Indenture has the same meaning when used
in this First Supplemental Indenture;

          (b)   capitalized terms used herein that are not otherwise defined
herein shall have the meaning assigned to such terms in the Indenture;

          (c)   a term defined anywhere in this First Supplemental Indenture has
the same meaning throughout;

          (d)   the singular includes the plural and vice versa;

          (e)   headings are for convenience of reference only and do not affect
interpretation;

                                  ARTICLE II
                         AMENDMENTS TO THE INDENTURE


SECTION 2.1

          Article One, Section 101 of the Indenture is amended to add the
following language between the definitions of "Place of Payment" and
"Redemption Date":

          "Project Finance Indebtedness" means indebtedness of a Subsidiary
(other than a Utility and other than the Company) secured by a Lien on any
property acquired, constructed or improved by such Subsidiary after the date of
this Indenture which Lien is created or assumed contemporaneously with, or
within 120 days after, such acquisition or completion of such construction or
improvement, or within six months thereafter pursuant to a firm commitment for
financing arranged with a lender or investor within such 120-day period, to
secure or provide for the payment of all or any part of the purchase price of
such property or the cost of such construction or improvement or on any
property existing at the time of acquisition thereof; provided that such a
Lien shall not apply to any property theretofore owned by any such Subsidiary
other than, in the case of any such construc-










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tion or improvement, any theretofore unimproved real property on which the 
property so constructed or the improvement is located; and provided further
that such indebtedness, by its terms, shall limit the recourse of any holder of
such Indebtedness (or trustee on such holder's behalf) in the event of any
default in such Indebtedness to the assets subject to such Liens and the
capital stock of, or the dividends received from, the Subsidiary issuing such
Indebtedness.  Notwithstanding the foregoing, Project Finance Indebtedness
shall include all Indebtedness that would constitute Project Finance
Indebtedness but for the fact that such Indebtedness was issued prior to the
date of this Indenture and taking into account the fact that the property
subject to the Lien may have been acquired prior to the date of this
Indenture."

SECTION 2.2.

          Article One, Section 101 of the Indenture is amended to add the
following language between the definitions of "U.S. Government Obligations"
and "Value":

          "Utility" shall mean any Subsidiary of the Company engaged in the
business of distributing natural gas at retail."

SECTION 2.3.

          Article Five, Section 501(4) of the Indenture is hereby amended in
its entirety to read as follows:

          "(4) any Event of Default under any series of Securities issued
     pursuant to this Indenture or any event of default, as defined in any
     other indenture, mortgage, or instrument under which there may be issued,
     or by which there may be secured or evidenced, any Indebtedness of the
     Company or a Subsidiary (whether such Indebtedness now exists or shall
     hereafter be created or incurred), but excluding Project Finance
     Indebtedness, shall occur and shall consist of default in the payment of
     such Indebtedness at the maturity thereof (after giving effect to any
     applicable grace period) or shall result in Indebtedness becoming or being
     declared due and payable prior to the date on which it would otherwise
     become due and payable, and such default in payment

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is not cured or such acceleration shall not be rescinded or annulled within 10
days after written notice to the Company from the Trustee or to the Company and
to the Trustee from the Holders of at least 10% in aggregate principal amount
of the Securities of that series at the time outstanding; provided that it
shall not be an Event of Default if the principal amount of Indebtedness (other
than Indebtedness represented by Securities issued pursuant to this Indenture)
which is not paid at maturity or the maturity of which is accelerated is less
than the amount equal to 1% of the Company's consolidated total assets
(determined as of its most recent fiscal year-end); provided further, that it
shall not be an Event of Default if the Indebtedness with respect to which such
default has occurred is Indebtedness of MCNIC Oil & Gas Company ("MOG")
(formerly Supply Development Group, Inc.) or its Subsidiaries and the
obligations of MCN and its Subsidiaries with respect to such Indebtedness
(other than MOG and its Subsidiaries) are no greater than the obligations of
MCN pursuant to the Support Agreement of MCN Corporation made as of August 23,
1995, as amended on October 4, 1995 (the "Supply Development Agreement") among
MCN, Supply Development Group, Inc. and certain of its Subsidiaries and does
not obligate payments by the obligor under such agreement with respect to
anything other than the payments specified in Paragraphs 3, 4 and 5 of the
Supply Development Agreement (limiting for these purposes the term "Material
Contracts" to the same general type of contracts for which MCN is obligated to
make payments under the Supply Development Agreement); provided further that
if, prior to a declaration of acceleration of the maturity of the Securities of
that series or the entry of judgment in favor of the Trustee in a suit pursuant
to Section 503, such default shall be remedied or cured by the Company or
waived by the holders of such Indebtedness, then the Event of Default hereunder
by reason thereof shall be deemed likewise to have been thereupon remedied,
cured or waived without further action on the part of either the Trustee or any
of the Holders of the Securities of that series, and provided further, that,
subject to Sections 601 and 602, the Trustee shall not be charged with
knowledge of any such default unless written notice of such 

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default shall have been given to the Trustee by the Company, by a holder or an
agent of a holder of any such Indebtedness, by the trustee then acting under
any indenture or other instrument under which such default shall have
occurred, or by the Holders of at least five percent in aggregate principal
amount of the Securities of that series at the time outstanding; or"

SECTION 2.4.

          The amendments set forth in Sections 2.1, 2.2 and 2.3 shall not be
effective as to any Security Outstanding of any series created prior to the
date hereof.

                                 ARTICLE III
                                MISCELLANEOUS

SECTION 3.1.    Ratification of Indenture.

          The Indenture, as supplemented by this First Supplemental Indenture,
is in all respects ratified and confirmed, and this First Supplemental
Indenture shall be deemed part of the Indenture in the manner and to the extent
herein and therein provided.

SECTION 3.2.    Governing Law.

          This First Supplemental Indenture shall be deemed to be a contract
made under the internal laws of the State of New York, and for all purposes
shall be construed in accordance with the laws of said State.

SECTION 3.3.    Separability.

          In case any one or more of the provisions contained in this First
Supplemental Indenture shall for any reason be held to be invalid, illegal or
unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other provisions of this First Supplemental Indenture but
this First Supplemental Indenture shall be construed as if such invalid or
illegal or unenforceable provision had never been contained herein or therein.

SECTION 3.4.    Counterparts.




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          This First Supplemental Indenture may be executed in any number of
counterparts each of which shall be an original; but such counterparts shall
together constitute but one and the same instrument.

SECTION 3.5.    Effectiveness.

          This First Supplemental Indenture shall be effective and binding when
executed by the Company and the Trustee.

SECTION 3.6.    Trustee Not Responsible for Recitals.

          The recitals herein contained are made by the Company and not by the
Trustee, and the Trustee assumes no responsibility for the correctness thereof. 
The Trustee makes no representation as to the validity or sufficiency of this
First Supplemental Indenture.

SECTION 3.7.    Performance by Trustee.

          The Trustee, for itself and its successors accepts the Trust of the
Indenture as amended by this First Supplemental Indenture and agrees to perform
this First Supplemental Indenture, but only upon the terms and conditions set
forth in the Indenture, including the terms and provisions defining and
limiting the liability and responsibility of the Trustee.



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        IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed, and their respective corporate
seals to be hereunto affixed and attested, all as of the day and year first
above written.

                                        MCN ENERGY GROUP INC.


                                        By  /s/ Sebastian Coppola
                                           -----------------------
                                           Name:  Sebastian Coppola
                                           Title: Senior Vice President
                                                  and Treasurer


Attest:

By: /s/ Daniel L. Schiffer
    ----------------------
    Daniel L. Schiffer
    Senior Vice President,
    General Counsel
       and Secretary


                                        
                                        NBD BANK
                                        as Trustee

                                        By /s/ James Khami
                                           -----------------------
                                           Name:  James Khami
                                           Title: Assistant Vice President


Attest:

By: Signature
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