SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549


                                  Schedule 13G

                    Under the Securities Exchange Act of 1934
                               (Amendment No. 3)*


                         Bellwether Exploration Company
                                (Name of Issuer)

                              Common Stock, no par
                                      value
                         (Title of Class of Securities)


                                   079-895-108
                                 (CUSIP Number)








*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).




                        (Continued on following page(s))

                                Page 1 of 5 Pages





- -------------------------------------------------------------------------------
CUSIP No.:  079-895-108                 13G                 Page 2 of 5 Pages
- -------------------------------------------------------------------------------
1           NAME OF REPORTING PERSON
            S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
            The Allstate Corporation
            36-3871531
- -------------------------------------------------------------------------------
2           CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP *         (a) [ ]
                                                                       (b) [ ]
            N/A
- ----------- -------------------------------------------------------------------
3           SEC USE ONLY


- ----------- -------------------------------------------------------------------
4           CITIZENSHIP OR PLACE OF ORGANIZATION
            Delaware

- ----------- -------------------------------------------------------------------
                            5        SOLE VOTING POWER
        NUMBER OF                    1,290,584
          SHARES
- --------------------------- -------- ------------------------------------------
       BENEFICIALLY         6        SHARED VOTING POWER
         OWNED BY                    0
           EACH
- --------------------------- -------- ------------------------------------------
  REPORTING PERSON WITH     7        SOLE DISPOSITIVE POWER

                                     1,290,584
- --------------------------- -------- ------------------------------------------
                            8        SHARED DISPOSITIVE POWER

                                     0
- --------------------------- -------- ------------------------------------------
- --------------------------- -------- ------------------------------------------
9           AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

            1,290,584
- ----------- -------------------------------------------------------------------
10          CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9)EXCLUDES CERTAIN SHARES*

            n/a
- ----------- -------------------------------------------------------------------
11          PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
            9.32%
- ----------- -------------------------------------------------------------------
12          TYPE OF REPORTING PERSON*
            HC
- ----------- -------------------------------------------------------------------
- ----------- -------------------------------------------------------------------

                      *SEE INSTRUCTION BEFORE FILLING OUT!





Item 1            (a)               Name of Issuer:

                                            Bellwether Exploration Company

                  (b)               Address of Issuer's Principal Executive 
                                    Offices:
                                            1331 Lamar, Suite 1455
                                            Houston, Texas 77010

Item 2            (a)               Name of Person Filing:

                                            The Allstate Corporation

                  (b)               Address of Principal Business Office:

                                            2775 Sanders Road
                                            Northbrook, Illinois 60062-6127

                  (c)               Citizenship:

                                            Delaware

                  (d)               Title of Class of Securities:
                                            Common Stock

                  (e)               CUSIP Number:    079-895-108


Item 3                              If this statement is filed pursuant to Rules
                                    13d-1(b),  or 13d-2(b),  check whether the
                                    person filing is a:

                  (a)  (  )         Broker or Dealer registered under Section 15
                                    of the Act

                  (b)  (  )         Bank as defined in section 3(a)(6) of the 
                                    Act

                  (c)  (  )         Insurance Company as defined in Section 3(a)
                                    (19) of the Act

                  (d)  (  )         Investment Company registered under section 
                                    8 of the Investment Company Act

                  (e)  (  )         Investment Adviser registered under section 
                                    203 of the Investment Advisers Act of 1940

                  (f)  (  )         Employee  Benefit Plan,  Pension Fund which 
                                    is subject to the provisions of the Employee
                                    Retirement  Income  Security  Act of  1974
                                    or  Endowment  Fund;  see subparagraph
                                    240.13d-1(b)(1)(ii)(F)

                  (g)  (XX)         Parent Holding Company,  in accordance with
                                    sub-paragraph  240.13d-1(b)(ii)(G)
                                    (Note:  See Item 7)

                  (h)  (  )         Group, in accordance with subparagraph 
                                    240.13d-1 (b)(1)(ii)(H)


                                Page 3 of 5 Pages





Item 4                     Ownership.

                                    If the  percent  of the class  owned,  as of
                                    December  31 of  the  year  covered  by  the
                                    statement,  or as of  the  last  day  of any
                                    month  described  in  Rule  13d-1(b)(2),  if
                                    applicable,  exceeds five  percent,  provide
                                    the  following  information  as of that date
                                    and  identify  those shares which there is a
                                    right to acquire.

                  (a)               Amount Beneficially Owned:
                                                               1,290,584

                  (b)               Percent of Class:
                                                               9.32%

                  (c)               Number of shares as to which such person (1)
                                    has:

                                          (i)  sole power to vote or to direct 
                                               the vote
                                                               1,290,584

                                         (ii)  shared power to vote or to direct
                                               the vote
                                                               0

                                        (iii)  sole power to dispose or to 
                                               direct the disposition of
                                                               1,290,584

                                         (iv)  shared power to dispose or to 
                                               direct the disposition of
                                                               0

Item 5                     Ownership of Five Percent or Less of a Class.

                           If this  statement  is being filed to report the fact
                           that as of the date hereof the  reporting  person has
                           ceased to be the  beneficial  owner of more than five
                           percent  of  the  class  of  securities,   check  the
                           following ( ).

Item 6                     Ownership of More than Five Percent on Behalf of 
                           Another Person.





- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
(1)      Allstate Insurance  Company, a wholly-owned  subsidiary of The Allstate
         Corporation, beneficially owns the shares of common stock of the Issuer
         listed above in Item 4(a).



                                Page 4 of 5 Pages





Item 7            Identification  and  Classification  of the Subsidiary Which 
                  Acquired the Security being Reported on by the Parent Holding 
                  Company.

                                    Allstate  Insurance  Company is an insurance
                                    company  as that term is  defined in Section
                                    3(a)(19) of the  Securities  Exchange Act of
                                    1934.

Item 8            Identification and Classification of Members of the Group.

                                    N/A

Item 9            Notice of Dissolution of Group.

                                    N/A

Item 10           Certification.

         By  signing  below I  certify  that,  to the best of my  knowledge  and
belief, the securities referred to above were acquired in the ordinary course of
business  and were not acquired for the purpose of and do not have the effect of
changing or  influencing  the control of the issuer of such  securities and were
not acquired in connection  with or as a participant in any  transaction  having
such purpose or effect.

Signature.

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.

Date:  September 9, 1997


                                                THE ALLSTATE CORPORATION

                                                By ALLSTATE INSURANCE COMPANY


                                                By: /s/ Mary J. McGinn
                                                    ------------------
                                                        Mary J. McGinn
                                                        Vice President












                                Page 5 of 5 Pages