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                                                                     EXHIBIT 4.3

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, AND MAY BE REOFFERED AND SOLD ONLY IF SO REGISTERED OR IF AN EXEMPTION
FROM REGISTRATION IS AVAILABLE.

                              PLAINS RESOURCES INC.
                                                                       Warrant 2

               Warrant for the Purchase of Shares of Common Stock

                                                                  150,000 shares

     FOR VALUE RECEIVED, PLAINS RESOURCES INC., a Delaware corporation (the
"Company"), hereby certifies that Highbridge International LLC, or its permitted
assigns (the "Holder"), is entitled to purchase from the Company, at any time or
from time to time commencing on the date hereof and prior to 5:00 P.M., Houston
time then current, on November 12, 2002, 150,000 fully paid and non-assessable
shares of the common stock, $.10 par value per share, of the Company for a
purchase price per share of $25.00 (the "Per Share Warrant Price").
(Hereinafter, (i) said common stock, together with any other equity securities
which may be issued by the Company with respect thereto or in substitution
therefor, is referred to as the "Common Stock," (ii) the shares of the Common
Stock purchasable hereunder are referred to as the "Warrant Shares," (iii) the
aggregate purchase price payable hereunder for the Warrant Shares is referred to
as the "Aggregate Warrant Price," and (iv) this Warrant and all warrants
hereafter issued in exchange or substitution for this Warrant are referred to as
the "Warrant".) The Aggregate Warrant Price is not subject to adjustment. The
number of Warrant Shares and the Per Share Warrant Price is subject to
adjustment as hereinafter provided. This Warrant has been issued as a result of
the transfer on May 20, 2002 by Shell Land & Energy Company to The Convertible
Fund LLC of that certain Company Warrant #1 for the Purchase of Shares of Common
Stock dated November 12, 1997 (the "Original Warrant") and the subsequent
transfer of the Original Warrant by The Convertible Fund LLC on July 17, 2002 to
Highbridge International LLC.

     1. Exercise of Warrant. This Warrant may be exercised, in whole at any time
or in part from time to time, commencing on the date hereof, and prior to 5:00
P.M., Houston time then current, on November 12, 2002, by the Holder by the
surrender of this Warrant (with the subscription form at the end hereof duly
executed) at the Company's offices in Houston, Texas, together with proper
payment of the Aggregate Warrant Price, or the proportionate part thereof if
this Warrant is exercised in part. Payment for Warrant Shares shall be made by
certified or cashier's bank check payable to the order of the Company. If this
Warrant is exercised in part, this Warrant must be exercised for a number of
whole shares of the Common Stock, and the Holder is entitled to receive a new
Warrant covering the Warrant Shares which have not been exercised. Upon such
surrender of this Warrant, the Company will (a) issue a certificate or
certificates in the name of the Holder for the largest number of whole shares of
the Common Stock to which the Holder shall be entitled (no fractional shares
being issuable upon exercise of this Warrant), and deliver the other securities
and properties receivable upon the exercise of this Warrant, or the
proportionate part thereof if this Warrant is exercised in part, pursuant to the
provisions of this Warrant. The Company shall pay all taxes and other expenses
payable in connection with the preparation, execution and delivery of stock
certificates pursuant to

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this Section 1. Unless and until the Warrant Shares are registered under the
Securities Act of 1933, as amended (the "Act") as provided for in Exhibit A-3 to
the Exchange Agreement pursuant to which the Original Warrant was issued,
certificates evidencing the Warrant Shares issued upon exercise of this Warrant
shall bear a restrictive legend regarding limitations on transferability of such
shares.

     2. Reservation of Warrant Shares; Listing. The Company agrees that, prior
to the expiration of this Warrant, the Company will at all times (a) have
authorized and in reserve, and will keep available, solely for issuance or
delivery upon the exercise of this Warrant, the shares of the Common Stock and
other securities and properties as from time to time shall be receivable upon
the exercise of this Warrant, and (b) keep the shares of the Common Stock
receivable upon the exercise of this Warrant listed upon notice of issuance on
the American Stock Exchange or such other national securities exchange as the
Common Stock of the Company may be listed from time to time.

     3. Protection Against Dilution.

     (a) In case the Company shall hereafter (i) pay a dividend or make a
distribution on its capital stock in shares of Common Stock, (ii) subdivide its
outstanding shares of Common Stock into a greater number of shares, (iii)
combine its outstanding shares of Common Stock into a smaller number of shares
or (iv) issue by reclassification of its Common Stock other securities of the
Company, the kind and amount of Common Stock and other securities shall be
adjusted so that the Holder of this Warrant upon the exercise hereof shall be
entitled to receive the number of shares of Common Stock or other securities of
the Company which he would have owned immediately following such action had this
Warrant been exercised immediately prior thereto. An adjustment made pursuant to
this Subsection 3(a) shall become effective immediately after the record date in
the case of a stock dividend or distribution and shall become effective
immediately after the effective date in the case of a subdivision, combination
or reclassification. If, as a result of an adjustment made pursuant to this
Subsection 3(a), the Holder of this Warrant thereafter surrendered for exercise
shall become entitled to receive shares of two or more classes of capital stock
or shares of Common Stock and other securities of the Company, the Board of
Directors (whose determination shall be made in its reasonable judgment) shall
determine the allocation of the adjusted Per Share Warrant Price between or
among shares of such classes or capital stock or shares of Common Stock and
other securities.

     (b) In case of any capital reorganization or reclassification, or any
consolidation or merger to which the Company is a party other than a merger or
consolidation in which the Company is a continuing corporation, or in case of
any sale or conveyance to another entity of the property of the Company as an
entirety or substantially as an entirety, or in the case of any statutory
exchange of securities with another corporation (including any exchange effected
in connection with a merger of a third corporation into the Company), the Holder
of this Warrant shall have the right thereafter to convert this Warrant into the
kind and amount of securities, cash or other property which he would have owned
or have been entitled to receive immediately after such reorganization,
reclassification, consolidation, merger, statutory exchange, sale or conveyance
had this Warrant been converted immediately prior to the effective date of such
reorganization, reclassification, consolidation, merger, statutory exchange,
sale or conveyance and in any such case, if necessary, appropriate adjustment
shall be made in the application of the provisions set forth in this Section 3
with respect to the rights and interests thereafter of the Holder of this
Warrant to the end that the provisions set forth in this

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Section 3 shall thereafter correspondingly be made applicable, as nearly as may
reasonably be, in relation to any shares of stock or other securities or
property thereafter deliverable on the exercise of this Warrant. The above
provisions of this Subsection 3(b) shall similarly apply to successive
reorganizations, reclassifications, consolidations, mergers, statutory
exchanges, sales or conveyances. In the event of a statutory merger, the issuer
of any shares of stock or other securities or property thereafter deliverable on
the exercise of this Warrant shall be responsible for all of the agreements and
obligations of the Company hereunder. Notice of any such reorganization,
reclassification, consolidation, merger, statutory exchange, sale or conveyance
and of said provisions so proposed to be made, shall be mailed to the Holder of
this Warrant not less than 20 days prior to such event.

     (c) Whenever the number of Warrant Shares purchasable upon the exercise of
this Warrant is adjusted, as herein provided, the Per Share Warrant Price shall
be adjusted by multiplying such Per Share Warrant Price immediately prior to
such adjustment by a fraction, of which the numerator shall be the number of
Warrant Shares purchasable upon exercise of this Warrant immediately prior to
such adjustment, and of which the denominator shall be the number of Warrant
Shares so purchasable immediately thereafter.

     (d) Whenever the number of Warrant Shares purchasable upon the exercise of
this Warrant or the Per Share Warrant Price is adjusted, as herein provided, the
Company shall promptly mail by first class mail, postage prepaid to the Holder
notice of such adjustment setting forth a brief statement of the facts requiring
such adjustment and the computation by which such adjustment was made.

     (e) In the event that the Company issues securities, makes a distribution
to its stockholders or undertakes some other capital change or transaction that
the Company's Board of Directors in its reasonable judgment determines is an
issuance, distribution, change or transaction that warrants an adjustment
similar to those provided in this Section 3 based upon the intent hereof but
with respect to which the provisions hereof are not specifically applicable,
adjustments to the number of shares or other securities purchasable and the
price of shares or other securities comparable to those provided in this Section
3 shall be made as a result of such issuance, distribution, change or
transaction.

     4. Fully Paid Stock. The Company agrees that the shares of the Common Stock
represented by each and every certificate for Warrant Shares delivered on the
exercise of this Warrant shall, at the time of such delivery, be validly issued
and outstanding, fully paid and non-assessable, and not subject to preemptive
rights.

     5. Limited Transferability. This Warrant is transferable or assignable by
the Holder and is so transferable only upon the books of the Company which it
shall cause to be maintained for the purpose. The Company may treat the
registered Holder of this Warrant as he or it appears on the Company's books at
any time as the Holder for all purposes. Any Warrant issued upon the transfer or
assignment of this Warrant will be dated the same date as this Warrant.
Provided, however, this Warrant may not be transferred unless it is registered
under the Act, or an exemption from such registration is available.

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     6. Loss, etc., of Warrant. Upon receipt of evidence satisfactory to the
Company of the loss, theft, destruction or mutilation of this Warrant, and of
indemnity reasonably satisfactory to the Company, if lost, stolen or destroyed,
and upon surrender and cancellation of this Warrant, if mutilated, the Company
shall execute and deliver to the Holder a new Warrant of like date, tenor and
denomination.

     7. Warrant Holder Not Shareholder. Except as otherwise provided herein,
this Warrant does not confer upon the Holder any right to vote or to consent to
or receive notice as a shareholder of the Company, as such, in respect of any
matters whatsoever, or any other rights or liabilities as a shareholder, prior
to the exercise hereof.

     8. Headings. The headings of this Warrant have been inserted as a matter of
convenience and shall not affect the construction hereof.

     9. Applicable Law. This Warrant shall be governed by and construed in
accordance with the law of the State of Delaware without giving effect to the
principles of conflicts of law thereof.

     IN WITNESS WHEREOF, PLAINS RESOURCES INC. has caused this Warrant to be
signed by its President or Vice President on July __, 2002 to be effective as of
the 12th day of November, 1997.

                               PLAINS RESOURCES INC.


                               By:    /s/ Timothy T. Stephens
                                      ------------------------------------------
                               Name:  Timothy T. Stephens
                               Title: Executive Vice President & General Counsel

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                                  SUBSCRIPTION

     The undersigned, ___________________, pursuant to the provisions of the
foregoing Warrant, hereby agrees to subscribe for and purchase _______________
shares of the Common Stock of PLAINS RESOURCES INC. covered by said Warrant, and
makes payment therefore in full at the price per share provided by said Warrant.

Dated:
       --------------


                                    Signature:
                                               ---------------------------------

                                    Address:

                                    --------------------------------------------

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                                   ASSIGNMENT

     FOR VALUE RECEIVED ____________________ hereby sells, assigns and transfers
unto _____________________ the foregoing Warrant and all rights evidenced
thereby, and does irrevocably constitute and appoint _________________,
attorney, to transfer said Warrant on the books of PLAINS

RESOURCES INC.

Dated:
       --------------


                                    Signature:
                                               ---------------------------------
                                    Address:

                                    --------------------------------------------

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                               PARTIAL ASSIGNMENT

     FOR VALUE RECEIVED _________________________ hereby assigns and transfers
unto ________________________ the right to purchase _________ shares of the
Common Stock of PLAINS RESOURCES INC. by the foregoing Warrant, and a
proportionate part of said Warrant and the rights evidenced hereby, and does
irrevocably constitute and appoint ____________________, attorney, to transfer
that part of said Warrant on the books of PLAINS RESOURCES INC.

Dated:
       --------------


                                    Signature:
                                               ---------------------------------
                                    Address:

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