SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13D

                                (AMENDMENT NO. 5)

                   Under the Securities Exchange Act of 1934*


                             Carrizo Oil & Gas, Inc.
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                                (Name of Issuer)


                     Common Stock, par value $.01 per share
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                         (Title of Class of Securities)


                                   144577 10 3
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                                 (CUSIP Number)


                                S. P. Johnson IV
                             Carrizo Oil & Gas, Inc.
                        14701 St. Mary's Lane, Suite 800
                              Houston, Texas 77079
                                 (281) 496-1352
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            (Name, Address and Telephone Number of Person Authorized
                     to Receive Notices and Communications)


                                February 11, 2004
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             (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 that is the subject of this Schedule 13D, and is filing this
schedule because of Sections 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), 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.

*The remainder of this cover page should 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
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 ("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).


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CUSIP NO.  144577 10 3

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1   NAME OF REPORTING PERSON
    S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

    S.P. Johnson IV
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2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
    (a) [ ]

    (b) [X]
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3   SEC USE ONLY


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4   SOURCE OF FUNDS*

    00
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5   CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d)
    OR 2(e) [ ]

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6   CITIZENSHIP OR PLACE OF ORGANIZATION

    United States of America
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                7   SOLE VOTING POWER
  NUMBER OF         703,890 shares (171,667 of which are issuable upon the
   SHARES           exercise of certain options)
BENEFICIALLY   -----------------------------------------------------------------
  OWNED BY      8   SHARED VOTING POWER
   EACH
 REPORTING          0 shares
  PERSON       -----------------------------------------------------------------
   WITH         9   SOLE DISPOSITIVE POWER
                    703,890 shares (171,667 of which are issuable upon the
                    exercise of certain options)
               -----------------------------------------------------------------
               10   SHARED DISPOSITIVE POWER

                    0 shares
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11   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     703,890 shares
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12   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*  [X]

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13   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11

     3.79%
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14   TYPE OF REPORTING PERSON*

     IN
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INTRODUCTORY NOTE.

         This Amendment No. 5 to Schedule 13D is being filed on behalf S. P.
Johnson IV ("Mr. Johnson") to supplement certain information set forth in the
Schedule 13D relating to securities of Carrizo Oil & Gas, Inc., a Texas
corporation (the "Company"), originally filed by Mr. Johnson on August 21, 1997
and amended by Amendment No. 1 filed on October 16, 1997, Amendment No. 2 filed
on January 13, 1998, Amendment No. 3 filed on January 6, 2000, and Amendment No.
4 filed on April 4, 2002 (as so amended, the "Original Statement"), with respect
to the Common Stock, par value $.01 per share (the "Common Stock"), of the
Company. Unless otherwise indicated, each capitalized term used but not defined
herein shall have the meaning assigned to such term in the Original Statement.

ITEM 4. PURPOSE OF TRANSACTION

         On December 29, 2003, Mr. Johnson made a charitable gift of 10,000
shares of Common Stock.

         On February 11, 2004, Mr. Johnson sold 75,000 shares of Common Stock
pursuant to the Underwriting Agreement dated February 5, 2004 (the "Underwriting
Agreement") by and among the Company, CIBC World Markets Corp., First Albany
Capital, Inc., Hibernia Southcoast Capital, Inc., and Johnson Rice & Company
L.L.C., as representative of the several underwriters named in Schedule I to the
Underwriting Agreement (the "Underwriters"), and the selling shareholders listed
on Schedule II to the Underwriting Agreement, including Mr. Johnson, (the
"Selling Shareholders"). Mr. Johnson sold an additional 68,860 shares of Common
Stock to the Underwriters pursuant to an over-allotment option in the
Underwriting Agreement on March 5, 2004. The price paid by the Underwriters for
shares sold pursuant to the Underwriting Agreement was $6.58 per share, net of
an underwriting discount of $.42 per share.

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

         Mr. Johnson beneficially owns an aggregate of 703,890 shares of Common
Stock (approximately 3.79% of the 18,572,720 shares deemed to be outstanding as
of March 5, 2004 (consisting of 18,401,053 shares of Common Stock currently
outstanding and 171,667 shares of Common Stock that can be acquired through the
exercise of options within 60 days of March 1, 2004)). Such ownership does not
include any beneficial ownership that may be attributed to Mr. Johnson as a
result of his being a party to certain shareholders agreements described in the
Original Statement. As a result of the transactions described under Item 4, Mr.
Johnson ceased to be the beneficial owner of more than five percent of the
outstanding shares of Common Stock on February 11, 2004, except to the extent
the beneficial ownership of other shareholders of the Common Stock is attributed
to him pursuant to those shareholder agreements.

ITEM 6. CONTRACTS, ARRANGEMENTS, UNDERSTANDINGS OR RELATIONSHIPS WITH RESPECT TO
        SECURITIES OF THE ISSUER.

         The Underwriting Agreement includes customary terms and conditions
regarding the sale of securities in a firm commitment underwritten offering,
including an over-allotment option pursuant to which the Underwriters could
purchase up to an additional 75,000 shares of Common Stock from Mr. Johnson on
or before March 5, 2004. The over-allotment option was exercised, and Mr.
Johnson sold an additional 68,860 shares on March 5, 2004. In addition, pursuant
to the terms of the Underwriting Agreement, Mr. Johnson and the other Selling
Shareholders agreed not to make any offer, sale, assignment, transfer,
encumbrance, contract to sell, grant of an option to purchase or other
disposition, directly or indirectly, of any Common Stock of the Issuer
beneficially owned on the date of the Underwriting Agreement or thereafter
acquired for a period of 90 days subsequent to the date of the Underwriting
Agreement, subject to certain exceptions, without the prior written consent of
CIBC World Markets Corp. The foregoing description of the Underwriting Agreement
is qualified in its entirety by reference to the text of such agreement, which
is filed as an exhibit to this Schedule 13D and is incorporated by reference
herein. See also Item 4. The shares sold by Mr. Johnson in this offering were
registered pursuant to an amended and restated registration rights agreement
dated December 15, 1999 (included as Exhibit 16 to the Original Filing).


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ITEM 7. MATERIAL TO BE FILED AS EXHIBITS.

         Exhibit 31     Lock-up Agreement, dated February 4, 2004, by and
                        between S.P. Johnson IV and CIBC World Markets, as
                        representative of the several underwriters listed in the
                        Underwriting Agreement dated February 5, 2004.

         Exhibit 32     Underwriting Agreement, dated February 5, 2004, by and
                        among Carrizo Oil & Gas, Inc., and CIBC World Markets
                        Corp., First Albany Capital, Inc., Hibernia Southcoast
                        Capital, Inc., and Johnson Rice & Company, L.L.C., as
                        representatives of the several underwriters named in
                        Schedule I to the Underwriting Agreement, and the
                        selling shareholders listed on Schedule II to the
                        Underwriting Agreement (incorporated by reference to the
                        Annual Report on Form 10-K for the year ended December
                        31, 2003).


         After reasonable inquiry and to the best of his knowledge and belief,
the undersigned certifies that the information set forth in this statement is
true, complete and correct.

Date:  March 24, 2004.


                                              /s/ S.P. Johnson IV
                                              ----------------------------------
                                              S.P. Johnson IV


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