UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                  ------------
                                  SCHEDULE 13D

  Information to be Included in Statements Filed Pursuant to Rule 13d-1(a) and
               Amendments thereto Filed Pursuant to Rule 13d-2(a)

                                (Amendment No. 1)

                            Callon Petroleum Company
--------------------------------------------------------------------------------
                                (Name of Issuer)

                     Common Stock, par value $0.01 per share
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                            13123X102 (Common Stock)
--------------------------------------------------------------------------------
                                 (CUSIP Number)

                                 Victor Friberg
                                Fred. Olsen & Co.
                               Fred. Olsensgate 2
                                0152 Oslo, Norway
--------------------------------------------------------------------------------
                  (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                 August 28, 2000
--------------------------------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

     If the filing  person has  previously  filed a statement on Schedule 13G to
report the acquisition  which is the subject of this Schedule 13D, and is filing
this schedule because of Rule 13d-1 (b)(3) or (4), check the following box [ ].

     Note.  Schedules  filed in paper format shall include a signed original and
five copies of the schedule,  including  all exhibits.  See Rule 13d-7 for other
parties to whom copies are to be sent.

                         (Continued on following pages)

                               (Page 1 of 5 Pages)
--------------------------------------------------------------------------------

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

     The  information  required on 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 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).







-----------------------------                    -------------------------------
CUSIP No.         13123X102           13D                      Page 2 of 5 Pages
-----------------------------                    -------------------------------

-------- -----------------------------------------------------------------------
   1
         NAME OF REPORTING PERSONS                               Ganger Rolf ASA
         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS                  N/A
-------- -----------------------------------------------------------------------
   2
         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*               (a) [ ]
                                                                         (b) [ ]
-------- -----------------------------------------------------------------------
   3
         SEC USE ONLY
-------- -----------------------------------------------------------------------
   4
         SOURCE OF FUNDS*                                                     WC
-------- -----------------------------------------------------------------------
   5
         CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
         TO ITEMS 2(d) or 2(e)                                               [ ]
-------- -----------------------------------------------------------------------
   6
         CITIZENSHIP OR PLACE OF ORGANIZATION                  Kingdom of Norway
--------------------------------- ------ ---------------------------------------
                                    7
           NUMBER OF                     SOLE VOTING POWER                     0
             SHARES
          BENEFICIALLY
            OWNED BY
              EACH
           REPORTING
          PERSON WITH
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    8
                                         SHARED VOTING POWER           1,839,386
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    9
                                         SOLE DISPOSITIVE POWER                0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                   10
                                         SHARED DISPOSITIVE POWER      1,839,386
-------- -----------------------------------------------------------------------
  11
         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
         PERSON                                                        1,839,386
-------- -----------------------------------------------------------------------
  12
         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
         CERTAIN SHARES*                                                     [ ]
-------- -----------------------------------------------------------------------
  13
         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)                13.7%
-------- -----------------------------------------------------------------------
  14
         TYPE OF REPORTING PERSON*                                            CO
-------- -----------------------------------------------------------------------


                      *SEE INSTRUCTIONS BEFORE FILLING OUT!







-----------------------------                    -------------------------------
CUSIP No.         13123X102           13D                      Page 3 of 5 Pages
-----------------------------                    -------------------------------

-------- -----------------------------------------------------------------------
   1
         NAME OF REPORTING PERSONS                                   Bonheur ASA
         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS                  N/A
-------- -----------------------------------------------------------------------
   2
         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*               (a) [ ]
                                                                         (b) [ ]
-------- -----------------------------------------------------------------------
   3
         SEC USE ONLY
-------- -----------------------------------------------------------------------
   4
         SOURCE OF FUNDS*                                                     WC
-------- -----------------------------------------------------------------------
   5
         CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
         TO ITEMS 2(d) or 2(e)                                               [ ]
-------- -----------------------------------------------------------------------
   6
         CITIZENSHIP OR PLACE OF ORGANIZATION                  Kingdom of Norway
--------------------------------- ------ ---------------------------------------
                                    7
           NUMBER OF                     SOLE VOTING POWER                     0
             SHARES
          BENEFICIALLY
            OWNED BY
              EACH
           REPORTING
          PERSON WITH
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    8
                                         SHARED VOTING POWER           1,839,386
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    9
                                         SOLE DISPOSITIVE POWER                0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                   10
                                         SHARED DISPOSITIVE POWER      1,839,386
-------- -----------------------------------------------------------------------
  11
         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
         PERSON                                                        1,839,386
-------- -----------------------------------------------------------------------
  12
         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
         CERTAIN SHARES*                                                     [ ]
-------- -----------------------------------------------------------------------
  13
         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)                13.7%
-------- -----------------------------------------------------------------------
  14
         TYPE OF REPORTING PERSON*                                            CO
-------- -----------------------------------------------------------------------


                      *SEE INSTRUCTIONS BEFORE FILLING OUT!







-----------------------------                    -------------------------------
CUSIP No.         13123X102           13D                      Page 4 of 5 Pages
-----------------------------                    -------------------------------

-------- -----------------------------------------------------------------------
   1
         NAME OF REPORTING PERSONS                                     AS Quatro
         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS                  N/A
-------- -----------------------------------------------------------------------
   2
         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*               (a) [ ]
                                                                         (b) [ ]
-------- -----------------------------------------------------------------------
   3
         SEC USE ONLY
-------- -----------------------------------------------------------------------
   4
         SOURCE OF FUNDS*                                                     OO
-------- -----------------------------------------------------------------------
   5
         CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
         TO ITEMS 2(d) or 2(e)                                               [ ]
-------- -----------------------------------------------------------------------
   6
         CITIZENSHIP OR PLACE OF ORGANIZATION                  Kingdom of Norway
--------------------------------- ------ ---------------------------------------
                                    7
           NUMBER OF                     SOLE VOTING POWER                     0
             SHARES
          BENEFICIALLY
            OWNED BY
              EACH
           REPORTING
          PERSON WITH
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    8
                                         SHARED VOTING POWER                   0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    9
                                         SOLE DISPOSITIVE POWER                0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                   10
                                         SHARED DISPOSITIVE POWER              0
-------- -----------------------------------------------------------------------
  11
         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
         PERSON                                                                0
-------- -----------------------------------------------------------------------
  12
         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
         CERTAIN SHARES*                                                     [X]
-------- -----------------------------------------------------------------------
  13
         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)                    0
-------- -----------------------------------------------------------------------
  14
         TYPE OF REPORTING PERSON*                                            CO
-------- -----------------------------------------------------------------------


                      *SEE INSTRUCTIONS BEFORE FILLING OUT!







-----------------------------                    -------------------------------
CUSIP No.         13123X102           13D                      Page 5 of 5 Pages
-----------------------------                    -------------------------------

-------- -----------------------------------------------------------------------
   1
         NAME OF REPORTING PERSONS                                    Invento AS
         S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS                  N/A
-------- -----------------------------------------------------------------------
   2
         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*               (a) [ ]
                                                                         (b) [ ]
-------- -----------------------------------------------------------------------
   3
         SEC USE ONLY
-------- -----------------------------------------------------------------------
   4
         SOURCE OF FUNDS*                                                     OO
-------- -----------------------------------------------------------------------
   5
         CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
         TO ITEMS 2(d) or 2(e)                                               [ ]
-------- -----------------------------------------------------------------------
   6
         CITIZENSHIP OR PLACE OF ORGANIZATION                  Kingdom of Norway
--------------------------------- ------ ---------------------------------------
                                    7
           NUMBER OF                     SOLE VOTING POWER                     0
             SHARES
          BENEFICIALLY
            OWNED BY
              EACH
           REPORTING
          PERSON WITH
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    8
                                         SHARED VOTING POWER                   0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                    9
                                         SOLE DISPOSITIVE POWER                0
                                         ---------------------------------------
                                  ------ ---------------------------------------
                                   10
                                         SHARED DISPOSITIVE POWER              0
-------- -----------------------------------------------------------------------
  11
         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
         PERSON                                                                0
-------- -----------------------------------------------------------------------
  12
         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
         CERTAIN SHARES*                                                     [X]
-------- -----------------------------------------------------------------------
  13
         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)                    0
-------- -----------------------------------------------------------------------
  14
         TYPE OF REPORTING PERSON*                                            CO
-------- -----------------------------------------------------------------------


                      *SEE INSTRUCTIONS BEFORE FILLING OUT!






This Amendment No. 1 ("Amendment No. 1") amends and supplements the statement on
Schedule 13D filed by Fred.  Olsen Energy ASA, Ganger Rolf ASA,  Bonheur ASA, AS
Quatro and AS Cinco on August 20, 1997 (the "Statement"). All terms used herein,
unless  otherwise  defined,  have the same  meanings  herein as set forth in the
Statement.

This Amendment No. 1 is being filed to remove F.O. Energy and Cinco as Reporting
Persons  hereunder  and to add  Invento AS  ("Invento")  as a  Reporting  Person
hereunder.  Items  2, 3, 4, 5 and 6 of the  Statement  are  hereby  amended  and
supplemented by the following information:

Item 1.   Security and Issuer

Item 1 of the Statement was originally as follows:

This  statement  relates to the  Common  Stock,  par value  $0.01 per share (the
"Common  Stock"),  of Callon  Petroleum  Company,  a  corporation  organized and
existing under the laws of the State of Delaware (the "Company"),  the principal
executive offices of which are located at 200 North Canal Street, P.O. Box 1287,
Natchez, Mississippi 39120.

Item 2.   Identity and Background

Item 2 of the Statement was originally as follows:

This  statement  is being  filed by (i) Fred.  Olsen  Energy  ASA, a joint stock
company  organized  and existing  under the laws of the Kingdom of Norway ("F.O.
Energy"),  (ii) Ganger  Rolf ASA, a public  joint stock  company  organized  and
existing  under the laws of the  Kingdom  of Norway and the owner of 100% of the
outstanding  capital stock of F.O. Energy ("Ganger Rolf"),  (iii) Bonheur ASA, a
public joint stock company  organized and existing under the laws of the Kingdom
of Norway and the owner of 49.0% of the outstanding capital stock of Ganger Rolf
("Bonheur"), (iv) A/S Quatro, a joint stock company organized and existing under
the laws of the  Kingdom  of  Norway  and the  owner of 6.7% of the  outstanding
capital  stock of Ganger  Rolf and  23.0% of the  outstanding  capital  stock of
Bonheur  ("Quatro")  and (v) A/S Cinco,  a joint  stock  company  organized  and
existing  under the laws of the  Kingdom  of Norway and the owner of 6.9% of the
outstanding  capital stock of Ganger Rolf and 23.0% of the  outstanding  capital
stock of Bonheur  ("Cinco"  and,  collectively  with F.O.  Energy,  Ganger Rolf,
Bonheur and Quatro, the "Reporting Persons").

The principal  business address and the principal  executive  offices of each of
F.O.  Energy,  Ganger  Rolf,  Bonheur,  Quatro  and Cinco are  located  at Fred.
Olsensgate 2, 0152 Oslo, Norway.

The principal business activity of F.O. Energy is the ownership and operation of
offshore  drilling and floating  production  vessels and the fabrication of such
vessels, all for use by the offshore oil and gas industry, conducted through its
subsidiaries.  The  principal  business  activities  of each of Ganger  Rolf and
Bonheur are shipping, transportation and offshore oil and gas industry services,
conducted  through  their  respective   subsidiaries.   The  principal  business
activities  of each of Quatro and Cinco are  holding and  managing  investments,
including in Ganger Rolf, Bonheur and other companies.

During the last five years  preceding  the date of this  statement,  none of the
Reporting  Persons nor, to the best of the knowledge and belief of the Reporting
Persons,  any director or executive officer of any of the Reporting Persons (all
of whom are set forth in Shedule A hereto,  incorporated  herein by  reference),
were convicted in a criminal proceeding (excluding traffic violations or similar
misdemeanors).  During the past five years preceding the date of this statement,
none of the  Reporting  Persons nor, to the best of the  knowledge and belief of
the Reporting  Persons,  any of the  individuals set forth in Schedule A, were a
party to a civil  proceeding of a judicial or  administrative  body of competent
jurisdiction  and as a  result  of  such  proceeding  were or are  subject  to a
judgment,  decree or final order enjoining future  violations of, or prohibiting
or mandating  activities  subject to, U.S.  Federal or State  securities laws or
finding any violations with respect to such laws.

This Amendment No. 1 amends and supplements Item 2 as follows:

This  Amendment  No. 1 is being filed by (i) Ganger Rolf,  (ii)  Bonheur,  (iii)
Quatro, the owner of 21.3% of the outstanding  capital stock of Bonheur and (iv)
Invento, the owner of 20.8% of the outstanding capital stock of Bonheur.

The principal  business address and the principal  executive  offices of Invento
are located at Fred.  Olsensgate 2, 0152 Oslo,  Norway.  The principal  business
activity of Invento is holding and managing investments, including in Bonheur.

Schedule  A to  the  Statement,  containing  information  with  respect  to  the
directors and executive officers of the Reporting Persons, is hereby amended and
superseded in its entirety by Schedule A hereto.

Item 3.   Source and Amount of Funds or Other Consideration

Item 3 of the Statement was originally as follows:

F.O. Energy and Fred.  Olsen Energy II AS, a Norwegian joint stock company which
has agreed to merge and is expected to be effectively  merged with and into F.O.
Energy on or about  August 29, 1997 ("F.O.  Energy  II"),  acquired  from Ganger
Rolf, Bonheur, A/S Borga, Fred. Olsen Limited and Fred. Olsen Finance Limited an
aggregate of 1,839,386  shares of Common  Stock (of which F.O.  Energy  acquired
919,693  shares of Common Stock and F.O.  Energy II acquired  919,693  shares of
Common  Stock) in  consideration  for an  aggregate  of  2,118,450  newly issued
Ordinary  Shares of F.O. Energy (of which 1,059,225 newly issued Ordinary Shares
of F.O.  Energy were issued in exchange for  1,059,225  Ordinary  Shares of F.O.
Energy  II upon the  merger  thereof  with and into  F.O.  Energy).  See Item 4,
Purpose of Transaction.

This Amendment No. 3 amends and supplements Item 3 as follows:

Ganger Rolf and Bonheur  jointly  purchased  from F.O.  Energy an  aggregate  of
1,839,386 shares of Common Stock for an aggregate purchase price of $26,119,281,
which amount was based on the average closing price per share of Common Stock on
the New York Stock Exchange over the 20 trading days preceding the initial offer
from Ganger Rolf and Bonheur to purchase  such  shares.  Ganger Rolf and Bonheur
each paid  $13,059,640.50  of the purchase price,  derived from their respective
working capital. See Item 4, Purpose of Transaction.

Item 4.   Purpose of Transaction

Item 4 of the Statement was originally as follows:

The shares of Common Stock the ownership of which is reported were acquired by
F.O. Energy for investment purposes.

F.O.  Energy and F.O.  Energy II were  formed in April  1997 by Ganger  Rolf and
Bonheur,  respectively,  for purposes of a corporate restructuring involving the
consolidation of substantially  all of Ganger Rolf's and Bonheur's  interests in
certain  businesses in the offshore drilling,  floating  production and offshore
fabrication  industries.  In connection  with such  corporate  restructuring  by
Ganger Rolf and Bonheur,  F.O.  Energy and F.O.  Energy II acquired  from Ganger
Rolf,  Bonheur,  A/S Borga,  Fred. Olsen Limited and Fred. Olsen Finance Limited
81,340,  81,340,  1,285,080,   128,964  and  262,662  shares  of  Common  Stock,
respectively,  on August 11, 1997 pursuant to two stock purchase agreements (the
"Stock Purchase  Agreements") entered into among F.O. Energy and F.O. Energy II,
respectively, and Ganger Rolf, Bonheur, A/S Borga, Fred. Olsen Limited and Fred.
Olsen Finance  Limited,  in  consideration  for an aggregate of 93,700,  93,700,
1,480,000,  148,550 and 302,500  newly  issued  Ordinary  Shares of F.O.  Energy
(following  the  merger  of  F.O.   Energy  II  with  and  into  F.O.   Energy),
respectively.  Ganger Rolf and Bonheur each directly own 50% of the  outstanding
capital stock of A/S Borga. In addition,  Quatro and Cinco each directly own 50%
of the outstanding capital stock of Flawhurst Limited,  which directly owns 100%
of the  outstanding  capital  stock  of  Fred.  Olsen  Limited,  which  in  turn
indirectly  owns 100% of the  outstanding  capital stock of Fred.  Olsen Finance
Limited.  John C.  Wallace,  a director  of the  Company,  is a director of F.O.
Energy and a director  of Ganger  Rolf,  Bonheur,  Quatro and Cinco,  as well as
other companies  associated with the Reporting  Persons,  including Fred.  Olsen
Limited.

Prior to the execution of the Stock  Purchase  Agreements,  each of Ganger Rolf,
Bonheur,  A/S Borga,  Fred.  Olsen Limited and Fred.  Olsen Finance Limited were
limited  partners in NOCO Holdings L.P., a Delaware limited  partnership  ("NOCO
Holdings"),  the limited partner with a 99% interest in NOCO Enterprises L.P., a
Delaware limited  partnership  ("NOCO  Enterprises") and the 100% shareholder of
NOCO Properties, Inc., a Delaware corporation ("NOCO Properties"), which in turn
is the general  partner with a 1% interest in NOCO  Enterprises.  NOCO Holdings,
NOCO Enterprises, NOCO Properties and NOCO Management Ltd., a Texas corporation,
the general partner of NOCO Holdings, are collectively referred to herein as the
"NOCO Entities".  Prior to the execution of the Stock Purchase Agreements,  NOCO
Enterprises  held 1,984,758  shares of Common Stock in the Company.  Immediately
prior  to the  execution  of the  Stock  Purchase  Agreements,  the  partnership
interest of each of Ganger Rolf,  Bonheur,  A/S Borga,  Fred.  Olsen Limited and
Fred. Olsen Finance Limited in NOCO Holdings L.P. were liquidated and the shares
of Common Stock of the Company  attributable to such partnership  interests,  or
81,340,  81,340,  1,285,080,   128,964  and  262,662  shares  of  Common  Stock,
respectively, were distributed to such entities.

NOCO  Enterprises  entered into a  Stockholders'  Agreement (the  "Stockholders'
Agreement")  dated  September 16, 1994,  with the Company and certain members of
the Callon family (the "Callon Family") and a Registration Rights Agreement (the
"Registration  Rights Agreement") dated September 16, 1994, with the Company. In
connection with F.O. Energy's acquisition of an aggregate of 1,839,386 shares of
Common  Stock of the  Company,  F.O.  Energy  has  become a party to each of the
Stockholders'  Agreement and the  Registration  Rights  Agreement,  in each case
pursuant to the respective terms thereof. For a description of the Stockholders'
Agreement  and  the  Registration  Rights  Agreement,  see  Item  6,  Contracts,
Arrangements,  Understandings or Relationships with Respect to Securities of the
Issuer.

F.O. Energy will review on a continuous basis its investment in the Common Stock
and  the  Company's  business  affairs  and  financial  condition,  as  well  as
conditions  in  the  securities   markets  and  general  economic  and  industry
conditions.  F.O.  Energy may in the future take such  actions in respect of its
investment  in  the  Common  Stock  as it  deems  appropriate  in  light  of the
circumstances  existing  from time to time.  Currently,  these  actions  include
continuing to hold the shares it now  beneficially  owns or disposing of shares.
Such dispositions  could be effected in private  transactions,  through a public
offering or, upon compliance with the rules under the Securities Act of 1933, as
amended (the "Securities Act"), in the open market.  Dispositions by F.O. Energy
and certain of its transferees are restricted by the terms of the  Stockholders'
Agreement  described in Item 6 hereof.  Additionally,  it is possible  that F.O.
Energy could seek to acquire additional shares, although it has no current plans
to do so. Any  acquisition  of shares could be effected in the open  market,  in
privately negotiated transactions,  or otherwise. Shares may be transferred from
time to time  among F.O.  Energy and its  affiliates.  Any sales,  purchases  or
transfers  or other  actions  described  herein may be made at any time  without
further prior notice.  In reaching any  conclusion as to the foregoing  matters,
F.O. Energy will take into consideration  various factors, such as the Company's
business  and  prospects,   other  developments   concerning  the  Company,  the
obligations of and other business opportunities  available to F.O Energy and its
affiliates,  developments  with  respect to F.O.  Energy's  businesses,  general
economic  conditions,  the  market  price for  shares of Common  Stock and stock
market conditions.

None of the  Reporting  Persons nor, to the best of the  knowledge and belief of
the Reporting  Persons,  any of the individuals set forth on Schedule A, has any
plans or proposals, except as described above, that relate to or would result in
(a) the acquisition by any person of additional securities of the Company or the
disposition  of  securities  of  the  Company;  (b) an  extraordinary  corporate
transaction,  such as a merger,  reorganization  or  liquidation,  involving the
Company or any of its subsidiaries;  (c) a sale or transfer of a material amount
of assets  of the  Company  or any of its  subsidiaries;  (d) any  change in the
present board of directors or management of the Company,  including any plans or
proposals  to change the  number or term of  directors  or to fill any  existing
vacancies on the board; (e) any material change in the present capitalization or
dividend  policy of the Company;  (f) any other material change in the Company's
business or corporate structure;  (g) changes in the Company's charter,  by-laws
or  instruments  corresponding  thereto,  or other  actions which may impede the
acquisition  of  control  of the  Company  by any  person;  (h) any class of the
Company's  securities  being  delisted  from a national  securities  exchange or
ceasing to be authorized to be quoted in an inter-dealer  quotation  system of a
registered  national  securities  association;  (i) any  class of the  Company's
equity securities becoming eligible for termination of registration  pursuant to
Section  12(g)(4)  of the  Securities  Exchange  Act of 1934,  as  amended  (the
"Exchange Act"); or (j) any action similar to any of those enumerated above.

This Amendment No. 1 amends and supplements Item 4 as follows:

Prior to August 28, 2000, F.O.  Energy held an aggregate of 1,839,386  shares of
Common  Stock in the Company as a strategic  investment.  In August  2000,  F.O.
Energy  determined that its holding of Common Stock in the Company was no longer
of strategic  importance and that the financial  resources available through the
sale of such  holding  could  be more  profitably  used in  connection  with the
development by F.O. Energy of its core business.  Ganger Rolf and Bonheur wished
to retain  beneficial  ownership of the Common Stock in the Company held by F.O.
Energy.  Accordingly,  on  August  28,  2000  Ganger  Rolf and  Bonheur  jointly
purchased from F.O. Energy an aggregate of 1,839,386  shares of Common Stock for
an  aggregate  purchase  price  of  $26,119,281.  Ganger  Rolf and  Bonheur  are
currently registered as the joint record owner of all of the 1,839,386 shares of
Common  Stock  formerly  owned by F.O.  Energy.  F.O.  Energy no longer owns any
Common Stock in the Company.

On December 18, 1998,  Quatro was demerged  with the result that the company was
divided  into two  companies,  Quatro and  Invento  (formerly  Quatroto  AS). In
December  1998,  Quatro and Invento  also  disposed  of all of their  respective
shares in Ganger Rolf and each acquired  additional  shares in Bonheur.  Each of
Quatro and Invento disclaims  beneficial ownership of the shares of Common Stock
in the Company owned by Ganger Rolf and Bonheur.

In December 1998,  Cinco disposed of all of its shares in Boneur,  including the
transfer  of certain  of such  shares to Quatro and  Invento,  and  additionally
disposed of certain of its shares in Ganger Rolf.  Cinco  currently owns 5.2% of
the shares in Ganger Rolf and no shares in Bonheur.

John C.  Wallace,  a director of the  Company,  is a director of Ganger Rolf and
Bonheur, as well as other companies associated with the Reporting Persons.

In connection with F.O. Energy's acquisition of an aggregate of 1,839,386 shares
of Common Stock of the Company,  F.O.  Energy  became a party the  Stockholders'
Agreement and the Registration  Rights  Agreement,  in each case pursuant to the
respective terms thereof.  The Stockholders'  Agreement terminated in accordance
with its own terms on  September  16,  1999.  In  connection  with  their  joint
acquisition of an aggregate of 1,839,386  shares of Common Stock of the Company,
Ganger  Rolf  and  Bonheur  became  a joint  party  to the  Registration  Rights
Agreement,  pursuant  to the  terms  thereof,  in  lieu of  F.O.  Energy.  For a
description  of the  Registration  Rights  Agreement,  see  Item  6,  Contracts,
Arrangements,  Understandings or Relationships with Respect to Securities of the
Issuer.

As a result of the transactions  described above,  neither F.O. Energy nor Cinco
(i) directly or indirectly  beneficially owns more than 5% of the Company,  (ii)
is party to any agreement to act together for the purpose of voting or disposing
of the Common Stock,  and (iii) is required to file  pursuant to Rule  13d-1(a).
Accordingly, F.O. Energy and Cinco are no longer Reporting Persons hereunder.

Ganger Rolf and Bonheur will review on a continuous  basis their  investment  in
the Common Stock and the Company's business affairs and financial condition,  as
well as conditions in the securities  markets and general  economic and industry
conditions.  Ganger  Rolf and  Bonheur  may in the future  take such  actions in
respect of their  investment  in the Common  Stock as they deem  appropriate  in
light of the circumstances existing from time to time. Currently,  these actions
include  continuing to hold the shares they now beneficially own or disposing of
shares. Such dispositions could be effected in private  transactions,  through a
public  offering or, upon compliance with the rules under the Securities Act, in
the open market.  Additionally,  it is possible that Ganger Rolf and/or  Bonheur
could  seek to  acquire  additional  shares,  although  neither  of them has any
current plans to do so. Any  acquisition of shares could be effected in the open
market,  in  privately  negotiated  transactions,  or  otherwise.  Shares may be
transferred from time to time among Ganger Rolf,  Bonheur and their  affiliates.
Any sales,  purchases or transfers or other actions described herein may be made
at any time without  further prior notice.  In reaching any conclusion as to the
foregoing matters,  Ganger Rolf and Bonheur will take into consideration various
factors,  such as the  Company's  business  and  prospects,  other  developments
concerning the Company,  the  obligations  of and other  business  opportunities
available  to Ganger  Rolf,  Bonheur  and their  affiliates,  developments  with
respect to Ganger Rolf's and Bonheur's businesses,  general economic conditions,
the market price for shares of Common Stock and stock market conditions.

None of the  Reporting  Persons nor, to the best of the  knowledge and belief of
the Reporting  Persons,  any of the individuals set forth on Schedule A, has any
plans or proposals, except as described above, that relate to or would result in
(a) the acquisition by any person of additional securities of the Company or the
disposition  of  securities  of  the  Company;  (b) an  extraordinary  corporate
transaction,  such as a merger,  reorganization  or  liquidation,  involving the
Company or any of its subsidiaries;  (c) a sale or transfer of a material amount
of assets  of the  Company  or any of its  subsidiaries;  (d) any  change in the
present board of directors or management of the Company,  including any plans or
proposals  to change the  number or term of  directors  or to fill any  existing
vacancies on the board; (e) any material change in the present capitalization or
dividend  policy of the Company;  (f) any other material change in the Company's
business or corporate structure;  (g) changes in the Company's charter,  by-laws
or  instruments  corresponding  thereto,  or other  actions which may impede the
acquisition  of  control  of the  Company  by any  person;  (h) any class of the
Company's  securities  being  delisted  from a national  securities  exchange or
ceasing to be authorized to be quoted in an inter-dealer  quotation  system of a
registered  national  securities  association;  (i) any  class of the  Company's
equity securities becoming eligible for termination of registration  pursuant to
Section  12(g)(4) of the Exchange Act; or (j) any action similar to any of those
enumerated above.

Item 5.   Interest in Securities of the Issuer

Item 5 of the Statement was originally as follows:

As of the date of this  statement,  F.O. Energy is the record owner of 1,839,386
shares of the  outstanding  Common Stock of the  Company,  equal to 31.9% of the
outstanding  Common Stock of the Company based on a total of 5,758,667 shares of
Common Stock of the Company outstanding as of December 31, 1996.

F.O.  Energy  has the  sole  power to vote and the  sole  power  to  dispose  of
1,839,386 shares of Common Stock of the Company. Each of Ganger Rolf and Bonheur
have the power to direct the vote and direct  the  disposition  of the shares of
Common  Stock of the  Company  owned by F.O.  Energy.  Each of Quatro  and Cinco
disclaims  beneficial  ownership  to the shares of Common  Stock of the  Company
owned by F.O. Energy.

Under the Stockholders'  Agreement, a group consisting of the Reporting Persons,
the NOCO  Entities  and the  members of the Callon  Family may be deemed to have
been formed  pursuant to Rule  13d-5(b)(1)  promulgated  under the Exchange Act.
Such  group  would be deemed  to have  beneficial  ownership,  for  purposes  of
Sections  13(g) and 13(d) of the Exchange  Act, of all equity  securities of the
Company  beneficially owned by such parties.  Such parties would, as of the date
of this  statement,  be deemed to  beneficially  own an  aggregate  of 3,545,171
shares of Common Stock, or approximately  61.6% of the foregoing total number of
shares reported to be outstanding (based in part on information  provided by the
Company).

The Reporting  Persons believe,  based upon information  provided to them by the
NOCO  Entities  and the  Company,  that the number and  percentage  of shares of
Common Stock beneficially owned by of the parties to the Stockholders' Agreement
other than the  Reporting  Persons  are as set forth in  Schedule B hereto.  The
aggregate number and percentage of shares of Common Stock  beneficially owned by
the NOCO  Entities  is  145,372  shares and 2.5%,  and by the  Callon  Family is
1,560,413 shares and 27.1%. The Reporting Persons disclaim beneficial  ownership
of the shares of Common Stock owned by the NOCO  Entities and the Callon  Family
and the existence of a group with the NOCO Entities and the Callon Family.

During  the  past 60 days  preceding  the  date of this  statement,  none of the
Reporting  Persons nor, to the best of the knowledge and belief of the Reporting
Persons,  any of the  individuals  set forth in  Schedule  A, has  effected  any
transaction in the shares of the Company, except as described in Item 3 above.

This Amendment No. 1 amends and supplements Item 5 as follows:

As of the date of this  statement,  Ganger Rolf and Bonheur are the joint record
owner of 1,839,386 shares of the outstanding Common Stock of the Company,  equal
to 13.7% of the outstanding  Common Stock based on a total of 13,397,706  shares
of Common Stock outstanding as of November 5, 2001. Ganger Rolf and Bonheur have
the joint  power to vote and the joint power to dispose of  1,839,386  shares of
Common Stock of the  Company.  Each of Quatro and Invento  disclaims  beneficial
ownership to the shares of Common Stock of the Company  owned by Ganger Rolf and
Bonheur.

Under the  Stockholders'  Agreement,  a group consisting of F.O. Energy,  Ganger
Rolf,  Bonheur,  Quatro,  Cinco, the NOCO Entities and the members of the Callon
Family could have been deemed to have been formed  pursuant to Rule  13d-5(b)(1)
promulgated  under the  Exchange  Act.  The  Stockholders'  Agreement,  however,
terminated  according to its own terms on  September  16,  1999.  The  Reporting
Persons  disclaim  (i) the current or previous  existence  of any such group and
(ii) beneficial ownership of any of the shares of Common Stock owned by the NOCO
Entities or the Callon Family.

During the past 60 days  preceding the date of this Amendment No. 1, none of the
Reporting  Persons nor, to the best of the knowledge and belief of the Reporting
Persons,  any of the  individuals  set forth in  Schedule  A, has  effected  any
transaction in the shares of the Company, except as described in Item 3 above.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to
Securities of the Issuer

Item 6 of the Statement was originally as follows:

Except as described in this  statement or in the  documents  referred to herein,
there are no contracts, arrangements,  understandings or relationships (legal or
otherwise)  among the  Reporting  Persons or, to the best of the  knowledge  and
belief of the Reporting Persons, any of the individuals set forth in Schedule A,
or between  such persons and any person with  respect to any  securities  of the
Company.

The Stockholders'  Agreement,  to which F.O. Energy became a party on August 11,
1997,  provides that members of the Callon  Family,  NOCO  Enterprises  and F.O.
Energy agree (i) to each vote for two  directors  nominated by the Callon Family
and NOCO Enterprises and F.O. Energy, respectively (ii) neither NOCO Enterprises
nor F.O.  Energy on the one hand nor the  members of Callon  Family on the other
hand will transfer their shares of Common Stock in connection  with or support a
transaction  involving  a Change of Control  or a  Fundamental  Change  (each as
defined in the  Stockholders'  Agreement)  without the consent of the other; and
(iii) that  neither  NOCO  Enterprises  nor F.O.  Energy on the one hand nor the
members of Callon  Family on the other hand will sell Common Stock without first
offering it to the other, except in limited  circumstances.  This right of first
refusal does not apply in certain circumstances,  including certain dispositions
pursuant  to Rule 144,  underwritten  offerings,  dispositions  to persons  that
following the acquisition  would be the beneficial  owner of less than 5% of the
outstanding  Common  Stock and  dispositions  made with the consent of the other
party. The transferee in such dispositions would generally not be required to be
subject to the Stockholders' Agreement. The right of first refusal also does not
apply to certain  dispositions to other parties to the Stockholders'  Agreement,
certain  dispositions  to persons  affiliated  with or  directly  or  indirectly
holding  interests in the F.O.  Energy or the NOCO  Entities,  entities that are
affiliated  with a party  to the  Stockholders'  Agreement  and  certain  family
members and trusts. The transferees in these dispositions would generally remain
subject to the Stockholders' Agreement.

The Registration Rights Agreement, to which F.O. Energy became a party on August
11, 1997,  requires that the Company  register Common Stock owned by F.O. Energy
and  NOCO  Enterprises   with  the  Securities  and  Exchange   Commission  (the
"Commission") for sale to the public in a firm commitment  public offering,  and
to include shares owned by them in registration  statements filed by the Company
with the  Commission  covering  the sale of  shares of  Common  Stock  except in
certain  circumstances.  Members  of  the  Callon  Family  have  entered  into a
substantially similar agreement with the Company. The Company will pay all costs
(excluding  underwriting  discounts  and  commissions)  of the first two  demand
registrations  under the registration rights agreement with F.O. Energy and NOCO
Enterprises,  one-half of the costs of the third  demand  registration  and F.O.
Energy  and/or  NOCO   Enterprises   will  pay  all  costs  of  any   subsequent
registrations.  Neither F.O. Energy nor NOCO Enterprises will be responsible for
costs of registrations  not demanded by such entity.  The Company has agreed not
to effect any public sale  (including by registering  securities held by others)
of any  securities  of the same class being  registered  by F.O.  Energy or NOCO
Enterprises for certain  specified  periods prior to and following the effective
date of registration  statements  under which F.O. Energy or NOCO Enterprises is
selling  securities.  F.O.  Energy,  NOCO  Enterprises and members of the Callon
Family  have each  similarly  agreed not to effect  sales of  securities  during
periods prior to and following the  effective  date of  registration  statements
demanded by each of them under their respective registration rights agreement.

The foregoing are summaries of certain provisions of the Stockholders' Agreement
and the  Registration  Rights  Agreement,  copies of which  have  been  filed as
Exhibits 1 and 2, respectively, hereto and are incorporated by reference herein;
and such  summaries  are  qualified  by,  and  subject  to,  the  more  complete
information contained in such agreements.

This Amendment No. 1 amends and supplements Item 6 as follows:

Except as  described in this  Amentment  No. 1 or in the  documents  referred to
herein,  there are no contracts,  arrangements,  understandings or relationships
(legal  or  otherwise)  among  the  Reporting  Persons  or,  to the  best of the
knowledge and belief of the Reporting Persons,  any of the individuals set forth
in  Schedule  A, or between  such  persons  and any person  with  respect to any
securities of the Company.

The Stockholders'  Agreement,  to which F.O. Energy became a party on August 11,
1997, terminated in accordance with its own terms on September 16, 1999.

The  Registration  Rights  Agreement,  to which Ganger Rolf and Bonheur became a
joint party on August 28, 2000,  requires that the Company register Common Stock
owned by Ganger Rolf and Bonheur and the NOCO  Enterprises  with the  Commission
for sale to the  public in a firm  commitment  public  offering,  and to include
shares owned by them in  registration  statements  filed by the Company with the
Commission  covering  the sale of  shares  of Common  Stock  except  in  certain
circumstances.  The Company will pay all costs (excluding underwriting discounts
and  commissions) of the first two demand  registrations  under the registration
rights agreement with Ganger Rolf and Bonheur and NOCO Enterprises,  one-half of
the costs of the third demand  registration  and Ganger Rolf and Bonheur  and/or
NOCO  Enterprises  will pay all costs of any subsequent  registrations.  Neither
Ganger Rolf and Bonheur nor NOCO  Enterprises  will be responsible  for costs of
registrations not demanded by such entity.  The Company has agreed not to effect
any public sale  (including  by  registering  securities  held by others) of any
securities of the same class being registered by Ganger Rolf and Bonheur or NOCO
Enterprises for certain  specified  periods prior to and following the effective
date of  registration  statements  under  which  Ganger Rolf and Bonheur or NOCO
Enterprises is selling  securities.  Ganger Rolf,  Bonheur and NOCO  Enterprises
have each  similarly  agreed not to effect sales of  securities  during  periods
prior to and following the effective date of registration statements demanded by
each of them under their respective registration rights agreement.

The  foregoing are summaries of certain  provisions of the  Registration  Rights
Agreement (as amended by the counterpart thereto,  dated August 28, 2000, a copy
of which has been  filed as Exhibit 1 hereto and is  incorporated  by  reference
herein),  and which  summary is qualified  by, and subject to, the more complete
information contained in the Registration Rights Agreement.

Item 7.   Material to be Filed as Exhibits

Exhibit    Description
---------- ----------------------

   1.      Counterpart, dated August 28, 2000, to Registration Rights Agreement,
           dated September 16, 1994, by and between Callon Petroleum Holding
           Company and NOCO Enterprises L.P., amended on August 11, 1997 by
           Fred. Olsen Energy ASA becoming a party thereto through the execution
           of a counterpart of the Registration Rights Agreement, and as amended
           as of August 28, 2000 by Ganger Rolf and Bonheur becoming a joint
           party thereto through the execution of the Counterpart.







                                                               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.

Dated: March 1, 2002

GANGER ROLF ASA


By: /s/ Anette S. Olsen
   --------------------------------
Name: Anette S. Olsen
Title: Managing Director


BONHEUR ASA


By: /s/ Anette S. Olsen
   --------------------------------
Name: Anette S. Olsen
Title: Managing Director


AS QUATRO


By: /s/ Anette S. Olsen
    -------------------------------
Name: Anette S. Olsen
Title: Managing Director


INVENTO AS


By: /s/ Anette S. Olsen
   --------------------------------
Name: Anette S. Olsen
Title: Managing Director






                                   Schedule A

            Directors and Executive Officers of the Reporting Persons

Name                          Present Principal Occupation or Employment,
                              Address and Citizenship

Ganger Rolf

Fred. Olsen                  Chairman of the  Board of  Directors, Ganger  Rolf
                             ASA and Bonheur ASA; Fred. Olsensgate 2, 0152 Oslo,
                             Norway; Norwegian

Anette S. Olsen              Managing   Director,   Fred.  Olsen  &  Co.;  Fred.
                             Olsensgate 2, 152 Oslo, Norway; Norwegian

Fridthjov Haavardsson        Senior Vice President, Finance, Fred.  Olsen & Co.;
                             Fred. Olsensgate 2, 0152 Oslo, Norway; Norwegian

John C. Wallace              Managing Director, Fred. Olsen Limited;  65 Vincent
                             Square, London SW1P 2RX, England ; Canadian
Bonheur

Fred. Olsen                  Chairman of the Board of Directors, Ganger Rolf ASA
                             and Bonheur  ASA;  Fred. Olsensgate 2,  0152  Oslo,
                             Norway; Norwegian

Anette S. Olsen              Managing   Director,   Fred.  Olsen  &  Co.;  Fred.
                             Olsensgate 2, 152 Oslo, Norway; Norwegian

Fridthjov Haavardsson        Senior Vice President, Finance, Fred.  Olsen & Co.;
                             Fred. Olsensgate 2, 0152 Oslo, Norway; Norwegian

John C. Wallace              Managing Director, Fred. Olsen Limited;  65 Vincent
                             Square, London SW1P 2RX, England ; Canadian
AS Quatro

Fred. Olsen                  Chairman of the Board of Directors, Ganger Rolf ASA
                             and Bonheur  ASA;  Fred. Olsensgate 2,  0152  Oslo,
                             Norway; Norwegian

Anette S. Olsen              Managing   Director,   Fred.  Olsen  &  Co.;  Fred.
                             Olsensgate 2, 152 Oslo, Norway; Norwegian

Fredrik T. Olsen             Director,  Fred. Olsen S.A.,  Spain;  Finca Belami,
                             Calle  Dr.  Zerolo  17,  38006 St. Cruz deTenerife,
                             Canary Islands, Spain; Norwegian
Invento AS

Fred. Olsen                  Chairman of the Board of Directors, Ganger Rolf ASA
                             and  Bonheur  ASA;  Fred.  Olsensgate 2, 0152 Oslo,
                             Norway; Norwegian

Anette S. Olsen              Managing  Director,   Fred.  Olsen  &  Co.;   Fred.
                             Olsensgate 2, 0152 Oslo, Norway; Norwegian

Fredrik T. Olsen             Director,  Fred.  Olsen  S.A., Spain; Finca Belami,
                             Calle  Dr. Zerolo 17,  38006 St . Cruz  deTenerife,
                             Canary Islands, Spain; Norwegian







                                                                       Exhibit 1

                  COUNTERPART TO REGISTRATION RIGHTS AGREEMENT

                     BY AND BETWEEN CALLON PETROLEUM COMPANY

                   (FORMERLY CALLON PETROLEUM HOLDING COMPANY)

                           AND NOCO ENTERPRISES, L.P.

                            DATED SEPTEMBER 16, 1994



     WHEREAS,  the  parties  have  caused this  Counterpart  to be executed  and
delivered by their  respective duly authorized  officers for purposes of Section
7.3 of the  above-mentioned  Registration  Rights  Agreement and for purposes of
confirming that the 1,839,836 shares of common stock of Callon Petroleum Company
to be acquired  jointly by Ganger Rolf ASA and Bonheur ASA  directly  from Fred.
Olsen Energy ASA are  "Registrable  Securities"  as defined in the  Registration
Rights Agreement; and

     WHEREAS,  Ganger Rolf ASA and Bonheur ASA agree to be bound by the terms of
the Registration Rights Agreement;

     IN WITNESS  WHEREOF,  this  Counterpart  is effective as of the 28th day of
August, 2000.

       CALLON PETROLEUM COMPANY

       By: /s/ Robert A. Mayfield

       Name: Robert A. Mayfield

       Title: Corporate Secretary

       GANGER ROLF ASA

       By: /s/ F. Haavardsson             By: /s/ J.C. Wallace

       Name: F. Haavardsson               Name: J.C. Wallace

       Title: Director                    Title: Director

       BONHEUR ASA

       By: /s/ F. Haavardsson             By: /s/ J.C. Wallace

       Name: F. Haavardsson               Name: J.C. Wallace

       Title: Director                    Title: Director