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                                                                    EXHIBIT 3(d)

                             PLAINS RESOURCES INC.



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       Certificate of Designation, Preferences and Rights of a Series of
       Preferred Stock by Resolution of the Board of Directors Providing
       for an Issue of 68,000 Shares of Preferred Stock Designated
       "Series F Cumulative Convertible Preferred Stock"
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     Plains Resources Inc., a Delaware corporation (hereinafter called the
"Company"), pursuant to the provisions of Section 151 of the General Corporation
Law of the State of Delaware does hereby state and certify that pursuant to the
authority expressly vested in the Board of Directors of the Company by the
Second Restated Certificate of Incorporation, as amended, the Board of
Directors, at a meeting thereof duly called and held on December 1, 1999, at
which meeting a quorum was present and acting throughout, duly adopted the
following resolutions providing for the issue of shares of Preferred Stock
hereinafter referred to, and further providing with respect to such issue of
shares of Preferred Stock for such powers, designations, preferences and
relative, participating, optional and other special rights, and the
qualifications, limitations or restrictions thereof, as are hereinafter set
forth, in addition to those set forth in said Second Restated Certificate of
Incorporation;

     Resolved, that pursuant to Article FOURTH of the Certificate of
Incorporation (which authorizes 2,000,000 shares of Preferred Stock, $1.00 par
value), the Board of Directors hereby provides for the issue of a series of
68,000 shares of Preferred Stock designated "Series F Cumulative Convertible
Preferred Stock"; and

     Resolved, that the powers, designations, preferences and relative,
participating, optional and other special rights, and the qualifications,
limitations or restrictions thereof, of the shares of the Series F Cumulative
Convertible Preferred Stock shall be as follows:

     Section 1.  Designation and Rank.  The designation of the series of
Preferred Stock created by this resolution shall be "Series F Cumulative
Convertible Preferred Stock" (hereinafter called this "Series"), and the number
of shares constituting this Series shall be 68,000.  Shares of this Series shall
have a stated value of $1,000 per share.  The number of authorized shares of
this Series may be reduced by further resolution duly adopted by the Board and
by the filing of a certificate pursuant to the provisions of the General
Corporation Law of the State of Delaware stating that such reduction has been so
authorized, but the number of authorized shares of this Series shall not be
increased, except as provided in Section 2 hereof.  The shares of this Series
shall rank prior to the Junior Stock (as defined in Section 10) as to
distribution of assets and payment of dividends.  The shares of this Series
shall be of equal rank as to distribution of assets and payment of dividends
with all other series of Preferred Stock except as provided in a certificate of
designation with regard to such other series of Preferred Stock filed pursuant
to Section 151 of the General Corporation Law of the State of Delaware with the
Secretary of State of the State of Delaware.
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     Section 2.  Dividends.

     (a)  Shares of this Series shall be entitled to receive, when and as
declared by the Board of Directors, dividends as provided in this Section 2 on
the stated value per share of this Series, and no more.  Such dividends shall be
cumulative, shall accrue (whether or not declared and whether or not there shall
be funds legally available for the payment of dividends) from the date of
original issue of such shares and shall be payable in arrears, out of assets
legally available therefor, when and as declared by the Board of Directors of
the Company, on April 1 and October 1 of each year, commencing April 1, 2000
(except that if any such date is a Saturday, Sunday or a legal holiday then such
dividend shall be payable without interest on the next day that is not a
Saturday, Sunday or legal holiday) (each six-month period (or such period from
the date of original issue until April 1, 2000) expiring on a dividend payment
date being referred to herein as a "Dividend Period").  Each of such dividends
shall be paid to the holders of record of shares of this Series as they appear
on the stock register of the Company on such record dates, not exceeding 30 days
preceding the payment dates thereof, as shall be fixed by the Board.  Dividends
on account of arrears for any past Dividend Periods may be declared and paid at
any time, without reference to any regular dividend payment date, to holders of
record on such date, not exceeding 45 days preceding the payment date thereof,
as may be fixed by the Board.

     (b)  With respect to each dividend declared and timely paid on shares of
this Series, the Company may pay a cash dividend at the Dividend Rate (as
defined in Section 10), or, at its option, and in lieu of payment in cash, the
Company may pay such dividend for any six Dividend Periods by issuing additional
fully paid and nonassessable shares, or fractions thereof, of this Series having
an aggregate stated value equal to the cash dividend otherwise payable.  Each
dividend that accrues during each Dividend Period shall be deemed to be timely
paid only if it is paid on the dividend payment date on which such Dividend
Period expires.  Any dividend not declared and timely paid on shares of this
Series may thereafter be paid only by (i) issuing additional fully paid and
nonassessable shares of this Series, or fractions thereof ("Arrearage Shares"),
having an aggregate stated value equal to the cash that would have been paid had
such dividend been timely paid in cash and (ii) paying an amount in cash equal
to the aggregate amount of cash dividends, if any, that would have accrued on
such Arrearage Shares had such Arrearage Shares been issued on the dividend
payment date for such dividend, or, at the Company's option, and in lieu of such
cash payment, issuing additional fully paid and nonassessable shares, or
fractions thereof, of this Series having an aggregate stated value equal to the
cash payment otherwise to be made.  Each fractional share of this Series
outstanding shall be entitled to a ratably proportionate amount of all dividends
accruing with respect to each outstanding share of this Series pursuant to
Section 2 hereof, and all such dividends with respect to such outstanding
fractional shares shall be fully cumulative and shall accrue (whether or not
declared) and shall be payable in the same manner and at such times as provided
for in Section 2 hereof with respect to dividends on each outstanding share of
this Series. The Board of Directors shall authorize additional shares of this
Series to be available for issuance as dividends if the number of authorized
shares of this Series is insufficient to continue accruing or paying dividends
in shares of this Series.

     (c)  No full dividends shall be declared or paid or set apart for payment
on Parity Stock (as defined in Section 10) or Junior Stock for any period unless
full cumulative dividends have been or

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contemporaneously are declared and paid or declared and a sum sufficient for the
payment thereof set apart for such payment on this Series for all Dividend
Periods terminating on or prior to the date of payment of such full cumulative
dividends. When dividends are not paid in full, as aforesaid, upon the shares of
this Series and of any other series of Parity Stock, all dividends declared upon
shares of this Series and of any other series of Parity Stock shall be declared
pro rata so that the amount of dividends declared per share on this Series and
such other series of Parity Stock shall in all cases bear to each other the same
ratio that accrued dividends per share on the shares of this Series and such
other series of Parity Stock bear to each other. Holders of shares of this
Series shall not be entitled to any dividend, whether payable in cash, property
or stock, in excess of full cumulative dividends, as herein provided, on this
Series. Except as set forth in Section 2(b) above, no interest, or sum of money
in lieu of interest, shall be payable in respect of any dividend payment or
payments on this Series that may be in arrears.

     (d)  So long as any shares of this Series are outstanding, no dividend
(other than a dividend in Junior Stock or other than as provided in Section 2)
shall be declared or paid or set aside for payment or other distribution
declared or made upon the Junior Stock, nor shall any Junior Stock be redeemed,
purchased or otherwise acquired for any consideration (or any moneys be paid to
or made available for a sinking fund for the redemption of any shares of Junior
Stock) by the Company (except by conversion into or in exchange for Junior
Stock) unless, in each case, the full cumulative dividends on all outstanding
shares of this Series then payable shall have been paid.

     (e)  Dividends payable on this Series for any period less than a full
Dividend Period shall be computed on the basis of the ratio of the number of
days in such partial period to the actual number of days in such full Dividend
Period.

     Section 3.  Redemption.

     (a)  On December 15, 2007, the Company shall redeem, to the extent it has
legally available funds therefor, all shares of this Series then outstanding at
a redemption price per share equal to the sum of 100% of the stated value of
such shares plus the Deemed Arrearage Value (as defined in Section 10) per
share.  At any time when the Company shall not have redeemed the full number of
shares of this Series required to be redeemed pursuant to this Section 3, no
dividends (other than in Junior Stock or other than as provided in Section 2)
shall be declared or paid or set aside for payment, or other distribution
declared or made, upon the Junior Stock, nor shall any Junior Stock be redeemed,
purchased or otherwise acquired for any consideration (or any moneys be paid to
or made available for a sinking fund for the redemption of any shares of any
such stock) by the Company (except by conversion into or in exchange for Junior
Stock), nor shall any Parity Stock be redeemed, purchased or otherwise acquired
for any consideration (or any moneys be paid to or made available for a sinking
fund for the redemption of any shares of any Parity Stock) by the Company
(except by conversion into or in exchange for Junior Stock), unless, in the case
of the mandatory redemption of, repurchase of, or fulfillment of a sinking fund
obligation in respect of, any other series of Parity Stock, payments made in
respect of the mandatory redemption of, repurchase of, or fulfillment of a
sinking fund obligation in respect of, this Series and all other series of
Parity Stock then issued and outstanding and entitled to such mandatory payments
are made pro rata, as nearly as practicable, so that the amounts of such
payments made on this Series and such other series of

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Parity Stock shall in all cases bear to each other the same ratio, as nearly as
practicable, that such mandatory payments required to be made on this Series and
such other series of Parity Stock bear to each other.

     (b)  From and after December 15, 2003, the Company, at its option, may
redeem shares of this Series, as a whole or in part, at any time or from time to
time, at the following redemption prices per share, in each case together with
the Deemed Arrearage Value per share:


REDEMPTION PRICE                       IF REDEEMED DURING THE PERIOD:

110% of stated value ................. through December 15, 2004.

108% of stated value ................. from December 15, 2004
                                       through December 15, 2005.

106% of stated value ................. from December 15, 2005
                                       through December 15, 2006.

104% of stated value ................. from December 15, 2006
                                       through December 15, 2007.

     (c)  In the event that fewer than all of the outstanding shares of this
Series are to be redeemed, the number of shares to be redeemed shall be
determined by the Board and the shares to be redeemed shall be determined in a
pro rata manner.

     (d)  At such time as the Company shall redeem shares of this Series, notice
of such redemption shall be given by first class mail, postage prepaid, mailed
not less than 30 nor more than 60 days prior to the redemption date, to each
holder of record of the shares to be redeemed, at such holder's address as the
same appears on the stock register of the Company.  Each such notice shall
state:  (i) the redemption date; (ii) the number of shares of this Series to be
redeemed and, if fewer than all the shares held by such holder are to be
redeemed, the number of such shares to be redeemed from such holder; (iii) the
redemption price; (iv) the place or places where certificates for such shares
are to be surrendered for payment of the redemption price; and (v) that
dividends on the shares to be redeemed will cease to accrue on such redemption
date.

     (e)  Notice having been mailed as aforesaid, from and after the redemption
date (unless default shall be made by the Company in providing money for the
payment of the redemption price) dividends on the shares of this Series so
called for redemption shall cease to accrue, and said shares shall no longer be
deemed to be outstanding, and all rights of the holders thereof as stockholders
of the Company (except the right to receive from the Company the redemption
price plus the Deemed Arrearage Value to the redemption date) shall cease.  Upon
surrender in accordance with said notice of the certificates for any shares so
redeemed (properly endorsed or assigned for transfer, if the Board shall so
require and the notice shall so state), such shares shall be redeemed by the
Company at the redemption price aforesaid.  In case fewer than all the shares
represented by any such

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certificate are redeemed, a new certificate shall be issued representing the
unredeemed shares without cost to the holder thereof.

     (f)  Any shares of this Series that shall at any time have been redeemed or
purchased by the Company, or exchanged for shares of Common Stock pursuant to
Section 7, shall, after such redemption, have the status of authorized but
unissued shares of Preferred Stock, without designation as to series until such
shares are once more designated as part of a particular series by the Board.

     (g)  Notwithstanding the foregoing provisions of this Section 3, if any
dividends on this Series are in arrears, no shares of this Series shall be
redeemed pursuant to Section 3 unless all outstanding shares of this Series are
simultaneously redeemed, and the Company shall not purchase or otherwise acquire
any shares of this Series; provided, however, that the foregoing shall not
prevent the purchase or acquisition of shares of this Series pursuant to a
purchase or exchange offer made on the same terms to holders of all outstanding
shares of this Series.

     Section 4.  Voting.  Except as provided in this Section 4 and except as
otherwise required by law, the holders of shares of this Series shall not have
any right or power to vote on any question or in any proceeding or to be
represented at or to receive notice of any meeting of holders of capital stock
of the Company.  On any matters on which the holders of shares of this Series
shall be entitled to vote, they shall be entitled to one vote for each share
held.  So long as any shares of this Series remain outstanding, the affirmative
vote or consent of the holders of a majority of the shares of this Series
outstanding at the time, given in person or by proxy, either in writing or at a
meeting, shall be necessary to permit, effect or validate (i) the authorization,
creation or issuance, or any increase in the authorized or issued amount, of any
class or series of Senior Stock (as defined in Section 10), (ii) the amendment,
alteration or repeal of any of the provisions of the Second Restated Certificate
of Incorporation, as amended, which would materially and adversely affect any
right, preference, privilege or voting power of shares of this Series or of the
holders thereof in a manner disproportionate to the effect thereof on the
holders of any other shares of the Company's capital stock and (iii) any merger,
consolidation or sale of all or substantially all of the assets of the Company
or any other similar transaction.

     Section 5.  Liquidation.  In the event of any complete liquidation,
dissolution or winding-up of the Company, whether voluntary or involuntary, the
holders of shares of this Series shall each be entitled to receive out of the
assets of the Company, whether such assets are capital or surplus, for each
share of this Series a sum equal to the Deemed Arrearage Value of such share
plus the stated value of each such share before any distribution shall be made
to the holders of Junior Stock of the Company, and if the assets of the Company
shall be insufficient to pay in full such amounts, then such assets shall be
distributed among such holders and the holders of any Parity Stock ratably in
accordance with the respective amounts that would be payable on such shares if
all amounts payable thereon were paid in full.  In the event of any complete
liquidation, dissolution or winding-up of the Company, whether voluntary or
involuntary, the holders of shares of this Series shall not be entitled to
receive the liquidation price of such shares held by them until the liquidation
price of all Senior Stock shall have been paid in full.

     Section 6.  Conversion.

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     (a)  Each share of this Series shall be convertible at the option of the
record holder thereof at any time prior to the third Trading Day before the
redemption date for such share, by presentation of the certificate representing
such share by the record holder in person or by registered mail, return receipt
requested with postage prepaid thereon, at the principal office of the Company,
and at such other offices, if any, as the Board of Directors may determine, into
the number of shares of fully paid and nonassessable shares of Common Stock
determined by dividing the sum of the stated value of each such share plus the
Deemed Arrearage Value by the Conversion Price in effect at the time of
conversion.

     (b)  The Company covenants that it will at all times reserve and keep
available, out of its authorized and unissued Common Stock solely for the
purpose of issuance upon conversion of this Series as herein provided, free from
preemptive rights or any other actual or contingent purchase rights of Persons
other than the holders of shares of this Series, such number of shares of Common
Stock as shall then be issuable upon the conversion of all outstanding shares of
this Series.  The Company covenants that all shares of Common Stock that shall
be so issuable shall upon issue be duly and validly issued and fully paid and
nonassessable.

     Section 7.  Exchange.

     (a) If, at any time after December 15, 2001, the Per Share Market Value of
the Common Stock is at least, and not less than, $21.60 (the "Threshold Price")
for any 60 consecutive Trading Days, then each outstanding share of this Series
shall be exchanged for the number of shares of fully paid and nonassessable
shares of Common Stock determined pursuant to subsection 7.

     (b)  If the conditions set forth in subsection 7(a) have been met, then the
number of shares of Common Stock for which each outstanding share of this Series
shall be exchanged pursuant to Section 7 shall be determined by dividing the sum
of the stated value of each such share plus the Deemed Arrearage Value of such
share by the Conversion Price in effect at the time of such exchange.

     (c)  Notwithstanding any other provision of this Section 7, in the event
that (i) no registration statement with respect to the shares of Common Stock to
be issued upon exchange of shares of this Series has been declared effective,
(ii) such registration statement has been declared effective but ceases to be
effective, (iii) the prospectus which is a part thereof cannot be used at the
time of the exchange, (iv) necessary consents and filings with any Governmental
Authority relating to the issuance of Common Stock and the exchange have not
been obtained, accomplished or waived or (v) the shares of Common Stock to be
issued upon exchange in accordance with Section 7(a) have not been approved for
listing on the principal securities exchange on which the Common Stock is then
listed, such exchange shall be delayed until such time as none of the foregoing
is continuing, provided that such exchange will occur on the Trading Day
following the first day that none of the foregoing is continuing and the Per
Share Market Value has equaled or exceeded the Threshold Price for 30
consecutive Trading Days.

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<PAGE>

     (d) The Company shall give notice of an exchange under this Section 7 by
first class mail, postage prepaid, mailed (i) not more than 10 business days
after the conditions required under Section 7(a) (and provided that none of the
conditions in Section 7(c) exist) have been met and (ii) not less than 30 nor
more than 60 days prior to the exchange date, to each holder of record of the
shares of this Series to be exchanged, at such holder's address as the same
appears on the stock register of the Company.  Each such notice shall state:
(i) that the Board of Directors of the Company has determined in good faith that
the conditions set forth in subsection 7(a) have been met and that none of the
conditions in Section 7(c) exist; (ii) the exchange date; (iii) the number of
shares of Common Stock to be exchanged for each share of this Series; (iv) the
place or places where certificates for such shares are to be surrendered in
exchange for shares of Common Stock; and (v) that dividends on the shares of
this Series to be exchanged will cease to accrue on such exchange date.

     (e)  Notice having been mailed as aforesaid, from and after the exchange
date, dividends on the shares of this Series so called for exchange shall cease
to accrue, and said shares shall no longer be deemed to be outstanding, and all
rights of the holders as holders of shares of this Series (except the right to
receive from the Company the number of shares of Common Stock issuable pursuant
to this Section 7) shall cease.  Upon surrender in accordance with said notice
of the certificates for shares of this Series so exchanged (properly endorsed or
assigned for transfer, if the Board shall so require and the notice shall so
state), such certificates shall be exchanged for certificates representing the
number of shares of Common Stock for which shares of this Series have been
exchanged.  Until so surrendered, certificates for shares of this Series shall
represent, after the exchange date, the number of shares of Common Stock for
which shares of this Series have been exchanged.  Share certificates
representing shares of this Series that are so surrendered shall be canceled.

     (f)  Notwithstanding the foregoing provisions of this Section 7, if any
dividends on this Series are in arrears, no shares of this Series shall be
exchanged pursuant to Section 7 unless all outstanding shares of this Series are
simultaneously exchanged, and the Company shall not purchase or otherwise
acquire any shares of this Series; provided, however, that the foregoing shall
not prevent the purchase or acquisition of shares of this Series pursuant to a
purchase or exchange offer made on the same terms to holders of all outstanding
shares of this Series.

     Section 8.  Adjustment of Conversion Price.

     (a)  The Conversion Price initially shall be $12.25 (the "Conversion
Price").  The Conversion Price shall be subject to adjustment from time to time
as follows:

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          (i)  If the Company, at any time while any shares of this Series are
     outstanding, shall (A) pay a stock dividend or stock dividends or otherwise
     make a distribution or distributions on shares of its capital stock payable
     in shares of Common Stock (or in securities convertible into shares of
     Common Stock), (B) except as set forth in clause (A) above, pay a stock
     dividend or make a distribution on shares of its capital stock payable in
     shares of its capital stock of any class other than Common Stock or a class
     convertible into Common Stock, (C) subdivide outstanding shares of Common
     Stock into a larger number of shares, (D) combine outstanding shares of
     Common Stock into a smaller number of shares, or (E) issue by
     reclassification of shares of Common Stock any shares of capital stock of
     the Company of any class or classes, then the Conversion Price in effect
     immediately prior to such action shall be adjusted so that the holder of
     any shares of this Series thereafter surrendered for conversion or
     exchanged shall be entitled to receive the number and class or classes of
     shares of the capital stock of the Company that he would have owned or have
     been entitled to receive immediately after the happening of any of the
     events described above, had such shares of this Series been converted or
     exchanged on or immediately prior to the record date for such dividend or
     distribution or the effective date of such subdivision, combination or
     reclassification, as the case may be.  Notwithstanding the foregoing, no
     adjustment in the Conversion Price shall be made by reason of the payment
     of dividends on shares of Preferred Stock in additional shares of Preferred
     Stock.  An adjustment made pursuant to this subsection 8 shall become
     effective immediately after the record date in the case of a dividend or
     distribution and shall become effective immediately after the effective
     date in the case of a subdivision, combination or reclassification.

          (ii) If the Company, at any time while any shares of this Series are
     outstanding, shall issue rights or warrants to all holders of Common Stock
     entitling them (for a period expiring within 45 days after the record date
     mentioned below) to subscribe for or purchase shares of Common Stock at a
     price per share less than the Conversion Price in effect on the record date
     mentioned below, then the Conversion Price shall be reduced by multiplying
     the Conversion Price in effect prior to such record date by a fraction, of
     which the denominator shall be the number of shares of Common Stock
     (excluding treasury shares, if any) outstanding on the date of issuance of
     such rights or warrants plus the number of additional shares of Common
     Stock offered for subscription or purchase, and of which the numerator
     shall be the number of shares of Common Stock (excluding treasury shares,
     if any) outstanding on the date of issuance of such rights or warrants plus
     the number of shares which the aggregate offering price of the total number
     of shares so offered would purchase at the Conversion Price.  Such
     adjustment shall be made whenever such rights or warrants are issued, and
     shall become effective immediately after the record date for the
     determination of stockholders entitled to receive such rights or warrants.
     However, upon the expiration of any right or warrant to purchase Common
     Stock the issuance of which resulted in an adjustment in the Conversion
     Price pursuant to this subsection 8, if any such right or warrant shall
     expire and shall not have been exercised, then the Conversion Price shall
     immediately upon such expiration, be recomputed and effective immediately
     upon such expiration be increased to the prices which they would have been
     (but reflecting any other adjustments in the Conversion Price made pursuant
     to the provisions of this Section 8 after the issuance of such rights or
     warrants) had the adjustment of the Conversion Price made upon the issuance
     of such rights



                                       8
<PAGE>

     or warrants been made on the basis of offering for subscription or purchase
     only that number of shares of Common Stock actually purchased upon the
     exercise of such rights or warrants actually exercised.

          (iii) If the Company, at any time while shares of this Series are
     outstanding, shall distribute to all holders of Common Stock evidences of
     its indebtedness or assets (excluding cash dividends or cash distributions
     paid out of earned surplus) or rights or warrants to subscribe for or
     purchase any security (excluding those referred to in subsection 8 above),
     then in each such case the Conversion Price shall be determined by
     multiplying the Conversion Price in effect prior to the record date fixed
     for determination of stockholders entitled to receive such distribution by
     a fraction, of which the denominator shall be the Conversion Price of
     Common Stock determined as of the record date mentioned above, and of which
     the numerator shall be the Conversion Price of the Common Stock, less the
     then fair market value (as determined by the Board of Directors of the
     Company in good faith, whose determination shall be conclusive if made in
     good faith; provided, however that in the event of a distribution or series
     of related distributions exceeding 10% of the net assets of the Company,
     then such fair market value shall be determined by a nationally recognized
     or major regional investment banking firm or firm of independent certified
     public accountants of recognized standing (which may be the firm that
     regularly examines the financial statements of the Company) selected in
     good faith by the Board of Directors of the Company, and in either case
     shall be described in a statement provided to all registered holders of
     this Series) of the portion of assets or evidences of indebtedness so
     distributed or such subscription rights applicable to one share of Common
     Stock.  Such adjustment shall be made whenever any such distribution is
     made and shall become effective immediately after the record date mentioned
     above.

          (iv) If the Company, at any time while any shares of this Series are
     outstanding, shall issue or sell shares of Common Stock (excluding stock
     issuances referred to in other provisions of this Section 8(a)) for a
     consideration per share that is less than the Conversion Price in effect on
     the date of such issuance or sale, then the Conversion Price shall be
     reduced by multiplying the Conversion Price in effect immediately prior to
     the date of such issuance or sale by a fraction, of which the denominator
     shall be the number of shares of Common Stock (excluding treasury shares,
     if any) outstanding on the date of such issuance or sale plus the number of
     additional shares of Common Stock issued or sold, and of which the
     numerator shall be the number of shares of Common Stock (excluding treasury
     shares, if any) outstanding on the date of such issuance or sale plus the
     number of shares that the aggregate consideration received or receivable by
     the Company for the total number of shares so issued or sold would purchase
     at the then Conversion Price. Such adjustment shall be made whenever such
     shares are issued, and shall become effective immediately after such
     issuance. If the consideration received or receivable by the Company for
     such issuance or sale of shares of Common Stock is not cash, the fair
     market value of such consideration shall be determined by the Board, an
     investment banking firm, or certified public accountants in the manner
     specified in subsection 8(b).

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<PAGE>

          (v)  If the Company, at any time while any shares of this Series are
     outstanding, shall issue rights, options, or warrants (excluding those
     referred to in other provisions of this Section 8(a)) which entitle the
     holders thereof to purchase shares of Common Stock (such rights, options,
     or warrants collectively referred to as "Purchase Rights") at a price per
     share less than the then Conversion Price on the date of the issuance of
     such Purchase Rights, then the Conversion Price shall be reduced by
     multiplying the Conversion Price in effect immediately prior to the date of
     issuance of such Purchase Rights by a fraction, of which the denominator
     shall be the number of shares of Common Stock (excluding treasury shares,
     if any) outstanding on the date of issuance of such Purchase Rights plus
     the number of additional shares of Common Stock offered for purchase, and
     of which the numerator shall be the number of shares of Common Stock
     (excluding treasury shares, if any) outstanding on the date of issuance of
     such Purchase Rights plus the number of shares of Common Stock that the
     aggregate consideration received or receivable by the Company in connection
     with the grant as well as the exercise of such Purchase Rights would
     purchase at such Conversion Price. Such adjustment shall be made whenever
     such Purchase Rights are issued, and shall become effective immediately
     after the issuance of such Purchase Rights. However, upon the expiration of
     any such Purchase Right the issuance of which resulted in an adjustment in
     the Conversion Price pursuant to this subsection 8(a)(v), if such Purchase
     Right shall not have been fully exercised, then the Conversion Price shall
     immediately upon such expiration be recomputed and effective immediately
     upon such expiration be increased to the prices which they would have been
     (but reflecting any other adjustments in the Conversion Price made pursuant
     to the provisions of this Section 8 after the issuance of such Purchase
     Rights) had the adjustment of the Conversion Price made upon the issuance
     of such Purchase Right been made on the basis of offering for purchase only
     that number of shares of Common Stock actually purchased upon the exercise
     of such Purchase Rights which were actually exercised. If the consideration
     for the Purchase Rights received or receivable by the Company for the grant
     or exercise of such Purchase Rights is not cash, the fair market value of
     such consideration shall be determined by the Board, an investment banking
     firm, or certified public accountants in the manner specified in subsection
     8(b).

          (vi)  No notification to the holders of any adjustment in the
     Conversion Price otherwise required by this Section 8 shall be required
     unless such adjustment would require an increase or decrease of at least 1%
     in such price; provided, however, that any adjustment which by reason of
     this subsection 8(a)(vi) is not required to be made shall be carried
     forward and taken into account in any subsequent adjustments, and that upon
     presentment of shares of this Series for conversion, all adjustments shall
     be made calculating the conversion rights of such holder.  All calculations
     under this Section 8 shall be made to the nearest cent or the nearest
     1/100th of a share, as the case may be.

          (vii)  Whenever the Conversion Price is adjusted, as herein provided,
     the Company shall promptly mail to each registered holder of shares of this
     Series a notice setting forth the Conversion Price after such adjustment
     and setting forth a brief statement of the facts requiring such adjustment.
     Such notice prepared in good faith shall be conclusive evidence of the
     correctness of such adjustment absent manifest error.

                                       10
<PAGE>

          (viii)  In case of any reclassification of the Common Stock, any
     consolidation or merger of the Company with or into another person, sale or
     transfer of all or substantially all of the assets of the Company or any
     compulsory share exchange pursuant to which share exchange the Common Stock
     is converted into other securities, cash or property, then the holders of
     the shares of this Series then outstanding shall have the right thereafter
     to convert such shares only into the kind and amount of shares of stock and
     other securities and property receivable upon or deemed to be held
     following such reclassification, consolidation, merger, sale, transfer or
     share exchange by a holder of a number of shares of the Common Stock of the
     Company into which such shares of this Series could have been converted
     immediately prior to such reclassification, consolidation, merger, sale,
     transfer or share exchange.

     This provision shall similarly apply to successive reclassifications,
     consolidations, mergers, sales, transfers or share exchanges.

          (ix) If:

               (A)  the Company shall declare a dividend (or any other
          distribution) on the Common Stock payable otherwise than in cash out
          of its earned surplus; or

               (B)  the Company shall declare a special nonrecurring cash
          dividend on or a redemption of its Common Stock; or

               (C)  the Company shall authorize the granting to the holders of
          the Common Stock of rights or warrants to subscribe for or purchase
          any shares of capital stock of any class or of any other rights; or

               (D)  the approval of any stockholders of the Company shall be
          required in connection with any reclassification of the Common Stock
          of the Company (other than a subdivision or combination of the
          outstanding shares of Common Stock), any consolidation or merger to
          which the Company is a party, any sale or transfer of all or
          substantially all of the assets of the Company, or any compulsory
          share exchange whereby the Common Stock is converted into other
          securities, cash or property; or

               (E) there shall be any voluntary or involuntary dissolution,
          liquidation or winding up of the affairs of the Company;

     then the Company shall cause to be filed at each office or agency
     maintained for the purpose of conversion of the shares of this Series, and
     shall cause to be mailed to the holders of record of the shares of this
     Series at their last addresses as they shall appear upon the stock books of
     the Company, at least 10 days prior to the applicable record date
     hereinafter specified, a notice stating (x) the date on which a record is
     to be taken for the purpose of such dividend, distribution, redemption,
     rights or warrants, or, if a record is not to be taken, the date as of
     which the holders of Common Stock of record to be entitled to such
     dividend, distribution, redemption, rights or warrants are to be
     determined, or (y) the date on which such reclassification, consolidation,
     merger, sale, transfer, share exchange, dissolution,

                                       11
<PAGE>

     liquidation or winding up is expected to become effective, and the date as
     of which it is expected that holders of Common Stock of record shall be
     entitled to exchange their shares of Common Stock for securities or other
     property deliverable upon such reclassification, consolidation, merger,
     sale, transfer, share exchange, dissolution, liquidation or winding up (but
     no failure to mail such notice or any defect therein or in the mailing
     thereof shall affect the validity of the corporate action required to be
     specified in such notice).

     (b) If at any time conditions shall arise by reason of action taken by the
Company, which, in the opinion of the Board of Directors of the Company, are not
adequately covered by the other provisions hereof and which might materially and
adversely affect the rights of the holders of shares of this Series, or in case
at any time any such conditions are expected to arise by reason of any action
contemplated by the Company, then the Board of Directors of the Company shall
appoint a nationally recognized or major regional investment banking firm or a
firm of independent certified public accountants of recognized standing (which
may be the firm that regularly examines the financial statements of the
Company), who shall give their opinion as to the adjustment, if any (not
inconsistent with the standards established in this Section 8), of the
Conversion Price (including, if necessary, any adjustment as to the securities
into which shares of this Series may thereafter be convertible or exchangeable)
which is or would be required to preserve without dilution the rights of the
holders of shares of this Series.  The Board of Directors of the Company shall
make the adjustment recommended forthwith upon the receipt of such opinion or
the taking of any such action contemplated, as the case may be; provided,
however, that no such adjustment of the Conversion Price shall be made which in
the opinion of the investment banking firm or firm of accountants giving the
aforesaid opinion would result in an increase of the Conversion Price to more
than the Conversion Price then in effect.

     (c)  Upon any adjustment of the Conversion Price pursuant to this Section
8, then the Threshold Price shall be adjusted, as of the date of such adjustment
of the Conversion Price, to that price determined by multiplying the Threshold
Price in effect immediately prior to such adjustment of the Conversion Price by
a fraction (i) the numerator of which shall be the Conversion Price in effect
immediately after such adjustment of the Conversion Price, and (ii) the
denominator of which shall be the Conversion Price in effect immediately prior
to such adjustment.

     Section 9.  Fractional Shares; Transfer Taxes; HSR Act.

     (a)  The Company shall not be required to issue stock certificates
representing fractions of shares of Common Stock, but may, if otherwise
permitted, make a cash payment in respect of any final fraction of a share based
on the Per Share Market Value at such time.  If the Company elects not, or is
unable, to make such a cash payment, the holder of a share of this Series shall
be entitled to receive, in lieu of the final fraction of a share, one whole
share of Common Stock.

     (b)  The issuance of certificates for shares of Common Stock on conversion
of this Series shall be made without charge to the holders thereof for any
documentary stamp or similar taxes that may be payable in respect of the issue
or delivery of such certificate, provided, that the Company shall not be
required to pay any tax that may be payable in respect of any transfer involved
in the issuance and delivery of any such certificate in a name other than that
of the holder of the shares of

                                       12
<PAGE>

this Series converted and the Company shall not be required to issue or deliver
such certificates unless or until the person or persons requesting the issuance
thereof shall have paid to the Company the amount of such tax or shall have
established to the satisfaction of the Company that such tax has been paid.

     (c)  The exercise by a holder of shares of this Series of the conversion
rights granted in Section 6 and the exercise by the Company of the exchange
rights as set forth in Section 7 are subject in all respects to and conditioned
upon compliance by the parties with the Hart-Scott-Rodino Antitrust Improvements
Act of 1976, as amended (the "HSR Act"), and rules and regulations promulgated
pursuant thereto, to the extent that said act, rules and regulations are
applicable to such exercise.  The Company and such holder agree to make such
filings with and provide such information to the Federal Trade Commission and
the Department of Justice with respect to such exercise as are required in
connection with the HSR Act in a timely manner and to join each others request
for early termination.  The Company and such holder will use such reasonable
efforts to obtain all governmental approval required to permit such exercise and
to cause early termination of the waiting period under the HSR Act.

     Section 10.  Definitions.  For the purposes hereof, the following terms
shall have the following respective meanings:

          "Arrearage Shares" has the meaning given such term in Section 2(b).

          "Common Stock" means shares now or hereafter authorized of the class
     of Common Stock, $.10 par value, of the Company presently authorized and
     stock of any other class into which such shares may hereafter have been
     reclassified or changed.

          "Conversion Price" has the meaning given such term in Section 8.

          "Deemed Arrearage Value" of a share of this Series means (i) the cash
     dividend accrued at the Dividend Rate on such share during the partial
     Dividend Period ending on the date of conversion, the date fixed for
     redemption, the exchange date or the date of payment upon liquidation, as
     the case may be, and (ii) if one or more dividends has accrued and has not
     been timely paid on such share, an amount in cash equal to $1,000
     multiplied by the number of whole and fractional shares of this Series that
     would have been issued as dividends on such share had all such accrued and
     unpaid dividends been timely paid in shares of this Series, together with
     the aggregate amount of cash dividends that would have accrued on such
     dividend shares to the date of conversion, the date fixed for redemption,
     the exchange date or the date of payment upon liquidation, as the case may
     be.

          "Dividend Rate" means 10% per annum.

          "Governmental Authority" means (i) the United States of America or any
     state within the United States of America and (ii) any court or any
     governmental department, commission, board, bureau, agency or other
     instrumentality of the United States of America or of any state within the
     United States of America.

                                       13
<PAGE>

          "Junior Stock" means the Common Stock of the Company and any other
     stock of the Company over which shares of this Series has a preference as
     to distribution of assets.

          "Parity Stock" means any stock of the Company ranking as to
     distribution of assets on a parity with this Series.

          "Per Share Market Value" means on any particular date (a) the last
     sale price per share of the Common Stock on such date on the principal
     stock exchange on which the Common Stock has been listed or, if there is no
     such price on such date, then the last price on such exchange on the date
     nearest preceding such date, or (b) if the Common Stock is not listed on
     any stock exchange, then the final bid price for a share of Common Stock in
     the over-the-counter market, as reported by the Nasdaq National Market at
     the close of business on such date, or the last sales price if such price
     is reported and final bid prices are not available, or (c) if the Common
     Stock is not quoted on the Nasdaq National Market, then the final bid price
     for a share of Common Stock in the over-the-counter market as reported by
     the National Quotation Bureau Incorporated (or any similar organization or
     agency succeeding to its functions of reporting prices), or (d) if the
     Common Stock is no longer publicly traded, then as determined by a
     nationally recognized or major regional investment banking firm or firm of
     independent certified public accountants of recognized standing (which may
     be the firm that regularly examines the financial statements of the
     Company) selected in good faith by the Board of Directors of the Company,
     provided, that none of the transactions related to the foregoing shall
     include purchases by any "affiliate" (as such term is defined in the
     General Rules and Regulations under the Securities Act of 1933) of the
     Company.

          "Person" means a corporation, an association, a partnership, an
     organization, a business, an individual, a government or political
     subdivision thereof or a governmental agency.

          "Preferred Stock" means the Company's Preferred Stock, $1.00 par
     value.

          "Senior Stock" means any shares or class of the Company that are by
     their terms expressly given priority over this Series as to distribution of
     assets on any liquidation of the Company.

          "Threshold Price " has the meaning given such term in Section 7(a).

          "Trading Day" means (a) a day on which the Common Stock is traded on
     the principal stock exchange on which the Common Stock has been listed, or
     (b) if the Common Stock is not listed on any stock exchange, then a day on
     which the Common Stock is quoted in the over-the-counter market, as
     reported by the Nasdaq Stock Market, or (c) if the Common Stock is not
     quoted on the Nasdaq Stock Market, then a day on which the Common Stock is
     quoted in the over-the-counter market as reported by the National Quotation
     Bureau Incorporated (or any similar organization or agency succeeding to
     its functions of reporting prices).

                                       14
<PAGE>

     IN WITNESS WHEREOF, said Plains Resources Inc. has caused this Certificate
to be signed by a duly authorized officer, this 14th day of December, 1999.



                                        PLAINS RESOURCES INC.



                                        By:  /s/ Phillip D. Kramer
                                             ----------------------------------
                                        Name:   Phillip D. Kramer
                                        Title:  Executive Vice President &
                                        Chief Financial Officer

ATTEST:



By: /s/ Michael R. Patterson
   -----------------------------------
Name:   Michael R. Patterson
Title:  Secretary


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