EXHIBIT 4.48
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                              OFFICER'S CERTIFICATE

         I, Una M. Power, Treasurer of Nexen Inc. (the "ISSUER"), pursuant to
authority granted to the undersigned by the Board of Directors of the Issuer
(and the Pricing Committee thereof), hereby establish the terms of the Issuer's
7.35% Subordinated Notes due 2043 (the "NOTES"), and pursuant to Section 3.01 of
the Indenture, dated as of November 4, 2003, between the Issuer and Deutsche
Bank Trust Company Americas, as Trustee (the "TRUSTEE") (as supplemented hereby,
the "INDENTURE") hereby certify as follows with respect to the Notes (unless
otherwise defined herein, capitalized terms shall have the meanings set forth in
the Indenture):

         Section 1.        The title of the Notes shall be "7.35% Subordinated
Notes due 2043". The Notes constitute a series of Securities as defined in the
Indenture. The Notes shall be issuable in fully registered form only in
denominations of $25 or any integral multiple thereof.

         Section 2.        The maximum aggregate principal amount of Notes that
may be authenticated and delivered under this Series Supplement shall be
$460,000,000, which amount includes the exercise of the over-allotment option
(the "OVER-ALLOTMENT OPTION") as set forth in the Underwriting Agreement, dated
as of October 28, 2003, by and among the Issuer and Citigroup Global Markets
Inc. and Merrill Lynch, Pierce, Fenner & Smith, Incorporated, as representatives
of the several underwriters named therein.

         Section 3.        The maturity date of the Notes is November 1, 2043.

         Section 4.        Global Form.

                  Section 4.1.      The Notes will be issued in global form (a
"GLOBAL NOTE") and shall represent such of the Notes as shall be specified
therein and shall represent the aggregate amount of Outstanding Notes from time
to time endorsed thereon and the aggregate amount of Outstanding Notes
represented thereby may from time to time be increased or decreased to reflect
exchanges. Such Global Note shall bear a legend substantially to the effect set
forth in the Form of Note attached hereto as Exhibit A. Any endorsement on a
Global Note to reflect the amount, or any increase or decrease in the amount, of
Outstanding Notes represented thereby shall be made by the Trustee in such
manner and upon instructions given in the Issuer Order to be delivered to the
Trustee pursuant to Section 3.03 or 3.04 of the Indenture. Subject to the
provisions of Section 3.03 of the Indenture and, if applicable, Section 3.04 of
the Indenture, the Trustee shall deliver and redeliver any Global Note in the
manner and upon instructions given by the Person or Persons specified therein or
in the applicable Issuer Order. If an Issuer Order pursuant to Section 3.03 or
Section 3.04 of the Indenture has been, or simultaneously is, delivered, any
instructions by the Issuer with respect to endorsement or delivery or redelivery
of a Global Note shall be in writing but need not comply with Section 1.02 of
the Indenture and need not be accompanied by an Opinion of Counsel.

         Notwithstanding the provisions of Sections 3.07 and 3.08 of the
Indenture, payment of principal of and interest on any Global Note shall be made
to the Holder or the Person or Persons specified from time to time by the Holder
by prior notice in writing to the Issuer and the Trustee.

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         Notwithstanding the provisions of Section 3.08 of the Indenture and
except as provided in the preceding paragraph, the Issuer, the Trustee and any
agent of the Issuer and the Trustee shall, and shall be entitled to, treat the
Holder of a Global Note as the Holder for all purposes.

                  Section 4.2.      Global Note.

                  (a)      A Global Note may only be issued to DTC or a nominee
of DTC and may be transferred, in whole but not in part, only to another nominee
of DTC, or to a successor depository selected or approved by the Issuer or to a
nominee of such successor depository.

                  (b)      If at any time (i) DTC or a successor depository, as
applicable, notifies the Issuer that it is unwilling or unable to continue as a
depository for such Global Note or (ii) if at any time DTC or a successor
depository, as applicable, shall no longer be a clearing agency registered or in
good standing under the Exchange Act or other applicable statute or regulation,
at which time DTC or a successor depository, as applicable, is required to be so
registered under the Exchange Act or other applicable statute or regulation and
in either clause (i) or (ii) above a successor depository is not appointed by
the Issuer within 90 days or (iii) the Issuer, in its sole discretion,
determines that such Global Note shall be exchangeable as described below, or
(iv) there shall have occurred and shall be continuing an Event of Default with
respect to the Notes and the Trustee has received through DTC or such successor
depository a request from an owner of beneficial interests in any Global Note to
deliver the Notes in certificated non-book entry, definitive registered form
without coupons, the Issuer will execute, and, subject to Article 3 of the
Indenture, the Trustee, upon written notice from the Issuer, will authenticate
and deliver the Notes in certificated non-book entry, definitive registered form
without coupons, in authorized denominations, and in an aggregate principal
amount equal to the principal amount of the Global Note in exchange for such
Global Note. In addition, the Issuer may at any time determine that the Notes
shall no longer be represented by a Global Note. In such event the Issuer will
execute, and subject to Section 3.03 of the Indenture, the Trustee, upon receipt
of an Officer's Certificate evidencing such determination by the Issuer, will
authenticate and deliver the Notes in certificated non-book entry, definitive
registered form without coupons, in authorized denominations, and in an
aggregate principal amount equal to the principal amount of the Global Note in
exchange for such Global Note. Upon the exchange of the Global Note for such
Notes in certificated non-book entry, definitive registered form without
coupons, in authorized denominations, and in an aggregate principal amount equal
to the principal amount of the Global Note, the Global Note shall be surrendered
to and cancelled by the Trustee. Such Notes in certificated non-book entry,
definitive registered form issued in exchange for the Global Note shall be
registered in such names and in such authorized denominations as DTC, or
successor depository, as the case may be, pursuant to instructions from the
direct or indirect participants or otherwise, shall instruct the Trustee. The
Trustee shall deliver such Notes to DTC for delivery to the Persons in whose
names such Notes are so registered.

         Section 5.        Interest.

                  (a)      The Notes will bear interest, payable in U.S.
Dollars, at the rate of 7.35% of the principal amount thereof per annum,
accruing from the date specified on the face of the Note until the principal
thereof becomes due and payable, and on any overdue principal and (to the extent
that payment of such interest is enforceable under applicable law) on any
overdue


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installment of interest at the interest rate stated above, compounded annually,
payable quarterly in arrears on February 1, May 1, August 1 and November 1 of
each year commencing on February 1, 2004, to the Person in whose name such Note
is registered, at the close of business on the Regular Record Date for such
interest installment, which shall be the preceding January 15, April 15, July 15
and October 15, respectively.

                  (b)      In the event that any date on which interest is
payable on the Notes is not a Business Day, then payment of the interest
otherwise due on such date will be made on the next succeeding day that is a
Business Day (and without any interest or other payment in respect of any such
delay), except that, if such Business Day is in the next succeeding calendar
year, then such payment shall be made on the immediately preceding Business Day,
in each case with the same force and effect as if made on such date. Interest
payments will be made in an amount equal to the interest accrued from and
including the immediately preceding Interest Payment Date in respect of which
interest has been paid or duly made available for payment (or, from and
including the date of issuance of the Notes, if no interest has been paid or
duly made available for payment) to but excluding the applicable Interest
Payment Date or Maturity Date, as the case may be.

         Section 6.        Common Shares Payment Election.

                  (a)      The Issuer may make a Common Shares Payment Election
on the Notes with respect to its obligation to pay the Redemption Price or
Maturity Amount on such Notes. In connection with the Common Shares Payment
Election, the Trustee shall: (i) accept delivery of Common Shares from the
Issuer and process the Common Shares in accordance with the Common Shares
Election Notice, (ii) accept bids with respect to, and consummate sales of, such
Common Shares, each as the Issuer shall direct in writing in its absolute
discretion, (iii) invest the proceeds of such sales in short-term U.S.
Government Obligations which mature prior to the applicable Payment Date and use
the proceeds received from such U.S. Governmental Obligations, together with any
proceeds from the sale of Common Shares not invested as aforesaid, to pay the
Redemption Price or the Maturity Amount at Maturity, as the case may be, and
(iv) perform any other action necessarily incidental thereto.

                  (b)      The Issuer may make a Common Shares Payment Election
by delivering a Common Shares Election Notice to the Trustee no later than the
earlier of (i) the date required by applicable law or the rules of any stock
exchange on which the Notes are then listed or (ii) 15 days prior to the Payment
Date to which the Common Shares Payment Election relates. The Trustee shall, in
accordance with the Common Shares Election Notice, deliver Common Shares Bid
Requests to investment banks, brokers or dealers specified in writing by the
Issuer in the Common Shares Election Notice. The Common Shares Election Notice
shall direct the Trustee to solicit and accept only such bids, and the Common
Shares Bid Request shall make the acceptance of any bid conditional on the
acceptance of such bids, that together shall provide for the delivery and sale
of Common Shares against payment of the Common Shares Election Amount (less any
amount attributable to any fractional Common Shares) on the Common Shares
Delivery Date.

                  The Common Shares Election Notice shall provide for, and all
such bids shall be subject to, the right of the Issuer, by delivering written
notice to the Trustee at any time


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prior to the consummation of the delivery and sale of the Common Shares on the
Common Shares Delivery Date, to withdraw the Common Shares Payment Election
(which shall have the effect of withdrawing the Common Shares Bid Request),
whereupon the Issuer shall be obligated to pay in cash the Common Shares Payment
Amount on such Payment Date. Any sale of Common Shares pursuant to this Section
6 may be made to one or more Persons whose bids are solicited, but all such
sales with respect to a particular Common Shares Payment Election shall take
place concurrently on the Common Shares Delivery Date.

                  (c)      The Trustee shall inform the Issuer promptly
following receipt of any bid or bids for Common Shares. The Trustee shall accept
such bid or bids as the Issuer (in its absolute discretion) shall direct in
writing, PROVIDED that the aggregate proceeds of all such sales, on the Common
Shares Delivery Date, must equal the Common Shares Election Amount (less any
amount attributable to any fractional Common Shares). In connection with any
bids so accepted, the Issuer, the Trustee and the applicable bidders shall, not
later than the Common Shares Delivery Date, enter into a Common Shares Purchase
Agreement reasonably satisfactory to the Issuer, the Trustee and the applicable
bidders and shall comply with all applicable laws, including the securities laws
of the U.S. and Canada, and any other applicable state, provincial or
territorial securities laws in the U.S. or Canada, the laws, rules and
regulations of any stock exchange on which the Common Shares are then listed and
the rules and regulations of any jurisdiction in which the Common Shares may be
offered for sale. The Trustee shall not be required to incur any obligation or
liability under the Common Shares Purchase Agreement other than those
obligations or liabilities that are expressly set forth in this Section 6; in
addition, the Trustee shall be provided upon request and may conclusively rely
upon an Opinion of Counsel with respect to compliance with applicable laws
(including the securities laws of the U.S. and Canada), as more particularly
described in the preceding sentence of this Section 6(c). The Issuer shall pay
all reasonable fees and expenses incurred by the Trustee in connection with the
Common Shares Purchase Agreements.

                  (d)      Provided that (i) all conditions specified in each
Common Shares Purchase Agreement to the closing of all sales thereunder have
been satisfied, other than the delivery of the Common Shares to be sold
thereunder against payment of the Common Shares Election Amount, and (ii) the
purchasers under the Common Shares Purchase Agreements shall be ready, willing
and able to perform thereunder, in each case on the Common Shares Delivery Date,
the Issuer shall, on the Common Shares Delivery Date, deliver to the Trustee the
Common Shares to be sold on such date, cash in an amount equal to the value of
any fractional shares and the accrued and unpaid interest in respect of the
Notes; and an Officer's Certificate to the effect that all conditions precedent
to such sales, including those set forth in this Indenture and in each Common
Shares Purchase Agreement, have been satisfied. Upon such deliveries, the
Trustee shall consummate such sales on such Common Shares Delivery Date by the
delivery of the Common Shares to such purchasers against payment to the Trustee
in immediately available funds of the purchase price therefor in an aggregate
amount equal to the Common Shares Election Amount (less any amount attributable
to any fractional Common Shares), whereupon the sole right of a Holder to
receive the Common Shares Payment Amount will be to receive same from the
Trustee out of the proceeds of such sale of Common Shares (plus any amount
received by the Trustee from the Issuer attributable to any fractional Common
Shares or the accrued and unpaid interest in respect of the Notes) in full
satisfaction of the Issuer's obligation to pay the Common Shares Payment Amount
and the Holder will have no further recourse to the


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Issuer in respect of such Common Shares Payment Amount, nor in respect of any
accrued and unpaid interest.

                  (e)      On the Common Shares Delivery Date, the Trustee shall
(i) use the sale proceeds of the Common Shares (together with any cash received
from the Issuer in respect of any fractional Common Shares and any cash received
from the Issuer to pay the accrued and unpaid interest in respect of the Notes)
to purchase to the extent the Trustee is able to do so short-term U.S.
Government Obligations which mature prior to Payment Date, and which the Trustee
is required to hold until Maturity (the "COMMON SHARES PROCEEDS INVESTMENT"),
and (ii) deposit the balance, if any, of such sale proceeds and cash, if any,
received in respect of fractional Common Shares and accrued and unpaid interest
in the Property Account. The Trustee shall hold the Common Shares Proceeds
Investment and all amounts from time to time deposited in the Property Account
under its exclusive control and shall hold the same (other than income earned on
any Common Shares Proceeds Investment) in an irrevocable trust for the benefit
of the Holders. To the extent that the Trustee shall receive any proceeds of the
Common Shares Proceeds Investment earlier than the Business Day immediately
preceding the applicable Payment Date, the Trustee shall deposit such proceeds
in the Property Account and, no later than one Business Day prior to the
applicable Payment Date, the Trustee shall deposit amounts from the proceeds of
the Common Shares Proceeds Investment in the Property Account to bring the
balance of the Property Account to the Common Shares Election Amount. On such
Payment Date, the Trustee shall apply the funds held in the Property Account to
payment of the Common Shares Payment Amount, plus accrued and unpaid interest on
the Notes, to the Holders as of the applicable Record Date and shall remit to
the Issuer, amounts, if any, in respect of income earned on the Common Shares
Proceeds Investments or otherwise in excess of the Common Share Election Amount.

                  (f)      The Issuer shall indemnify and hold harmless the
Trustee, its officers, directors, employees, representatives and agents, and (on
an after-tax basis) the Holders and any Person who controls any Holder within
the meaning of any applicable securities laws, from and against any and all
losses, claims, damages and liabilities (including, without limitation, any
legal or other expenses reasonably incurred by any such Person in connection
with defending or investigating any such action or claim) caused by or arising
in connection with any Common Shares Payment Election or any withdrawal thereof,
except in each case for any such losses, claims, damages or liabilities caused
by any such Person's gross negligence or willful misconduct. If the
indemnification provided for in this paragraph shall be unavailable to an
indemnified person or insufficient in respect of any losses, claims, damages or
liabilities referred to herein, then the Issuer shall contribute to the amount
paid or payable by such indemnified Person as a result of such losses, claims,
damages or liabilities in such proportion as is appropriate to reflect the
relative fault of the Issuer and such indemnified Person and any other equitable
considerations.

                  (g)      Notwithstanding the foregoing, the Issuer shall not
be permitted to satisfy its obligations to pay the Redemption Price or the
Maturity Amount by making a Common Shares Payment Election pursuant to this
Section 6 if, on the Common Shares Delivery Date, the Common Shares are not then
listed on a significant stock exchange in Canada or the U.S.


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                  (h)      Neither the Issuer's making of a Common Shares
Payment Election nor the consummation of sales of Common Shares on the Common
Shares Delivery Date will (i) result in the Holders not being entitled to
receive on the applicable Payment Date cash in an aggregate amount equal to the
Redemption Price or Maturity Amount payable plus, in each case, accrued and
unpaid interest and other amounts, if any, on the Notes on such Payment Date, as
the case may be, or (ii) entitle or oblige such Holders to receive any Common
Shares in satisfaction of the Issuer's obligation to pay such Redemption Price
or Maturity Amount of the Notes.

                  (i)      Pursuant to and in accordance with Section 6.03(g) of
the Indenture, the Issuer acknowledges and agrees that the Trustee shall be
entitled to perform its duties under this Section 6 either directly or by or
through agents, attorneys, custodians or nominees.

         Section 7.        Redemption. The Issuer may redeem, in accordance with
this Section 7, the Notes at its option, in whole or in part, at any time and
from time to time, on or after November 4, 2008 at a Redemption Price equal to
100% of the principal amount thereof plus accrued and unpaid interest thereon to
the Redemption Date.

         Section 8.        Sinking Fund. The Notes are not subject to a sinking
fund or other analogous fund requirement.

         Section 9.        Definitions.

                  Section 9.1.      The following terms shall have the meanings
indicated:

                  "COMMON SHARES" means common shares without nominal or par
value in the capital of the Issuer.

                  "COMMON SHARES BID REQUEST" means a request for bids made in
accordance with the Common Shares Election Notice and which makes the acceptance
of any bid conditional on the acceptance of sufficient bids to allow for the
payment of the Common Shares Election Amount on the Common Shares Delivery Date.

                  "COMMON SHARES DELIVERY DATE" means a date, no more than 90
days and no less than one Business Day prior to the Payment Date, upon which
Common Shares are delivered by the Issuer for purchase pursuant to a Common
Shares Election Notice.

                  "COMMON SHARES ELECTION AMOUNT" means the aggregate amount of
the proceeds, based on the bids obtained pursuant to the Common Shares Bid
Request, of the sale of Common Shares on a Common Shares Delivery Date equal to
and not exceeding the Common Shares Payment Amount.

                  "COMMON SHARES ELECTION NOTICE" means a written notice made by
the Issuer to the Trustee specifying:

                           (i)      that the election relates to an obligation
                                    to pay one of the Redemption Price or the
                                    Maturity Amount;


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                           (ii)     the payment to which the election relates
                                    and the Payment Date;

                           (iii)    the amount of the payment the Issuer
                                    proposes to satisfy by the delivery of
                                    Common Shares which amount shall be
                                    designated by the Issuer in such notice as
                                    the Common Shares Payment Amount;

                           (iv)     the Persons from whom the Trustee shall seek
                                    bids to purchase the Common Shares and the
                                    parameters of such bids, which may include
                                    minimum number of Common Shares, minimum
                                    price per Common Share, timing for closing
                                    for bids and such other matters as the
                                    Issuer may specify; and

                           (v)      the Trustee shall solicit and accept only
                                    those bids which comply with such notice.

                  "COMMON SHARES PAYMENT AMOUNT" means the amount due to Holders
on the Payment Date designated by the Issuer as the "Common Shares Payment
Amount" in a Common Shares Election Notice.

                  "COMMON SHARES PAYMENT ELECTION" means an election to pay the
Redemption Price or Maturity Amount on the Payment Date by the delivery of
Common Shares.

                  "COMMON SHARES PURCHASE AGREEMENT" means an agreement in
customary form among the Issuer, the Trustee and the Persons making acceptable
bids pursuant to a Common Shares Bid Request which complies with all applicable
laws, including the Securities Act, the Exchange Act, the applicable securities
laws of Canada and any other applicable state, provincial or territorial
securities laws in the U.S. or Canada, the rules and regulations of any stock
exchange on which the Common Shares are then listed and the laws, rules and
regulations of any jurisdiction in which the Common Shares may be offered for
sale.

                  "DTC" means The Depository Trust Company, New York, New York,
its successors or any other depository appointed in its stead in accordance with
Section 4.2 of this Officer's Certificate.

                  "MATURITY AMOUNT" means the principal of and premium, if any,
on the Notes at Maturity.

                  "MOODY'S" means Moody's Investors Service, Inc., or any
successor thereto.

                  "PAYMENT DATE" means the date on which a payment of the
Redemption Price or Maturity Amount is due.

                  "PREFERRED SECURITIES DUE 2047" means the Issuer's 9.75%
Junior Subordinated Debentures due October 30, 2047 issued pursuant to an
indenture dated as of October 30, 1998 between the Issuer and IBJ Schroder Bank
& Trust Company, as trustee.


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<PAGE>

                  "PREFERRED SECURITIES DUE 2048" means the Issuer's 9.375%
Junior Subordinated Debentures due March 31, 2048 issued pursuant to an
indenture dated as of February 9, 1999 between the Issuer and IBJ Whitehall Bank
& Trust Company, as trustee.

                  "PROPERTY ACCOUNT" means a segregated non-interest bearing
trust account, established and maintained by, in the name of and under the
exclusive control of the Trustee as custodian for and on behalf of the Holders,
which account shall be maintained with the Trustee or a banking institution
whose long-term unsecured indebtedness has a rating of at least "A" with
Standard & Poor's, or at least "A" with Moody's or an equivalent rating assigned
by a "nationally recognized statistical rating organization", as that term is
defined for the purposes of Rule 436(g) under the Securities Act. Funds
deposited in the Property Account shall be held uninvested until disbursed in
accordance with this Indenture.

                  "SECURITIES ACT" means the Securities Act of 1933, as amended
from time to time, and the rules and regulations promulgated thereunder.

                  "STANDARD & POOR'S" means Standard & Poor's Rating Services, a
division of The McGraw-Hill Companies, Inc., or any successor thereto.

                  Section 9.2.      The definition of "SENIOR INDEBTEDNESS" is
hereby amended to include in the list of exceptions to what constitutes Senior
Indebtedness following clause (vi) of the definition: "and (3) the Preferred
Securities due 2047 outstanding on the date hereof and the Preferred Securities
due 2048 outstanding on the date hereof (it being understood that the Notes rank
senior in right of payment to the Preferred Securities due 2047 and the
Preferred Securities due 2048)."

         Section 10.       The Notes will be represented by one or more global
Notes as described under the caption "Description of the Subordinated Notes --
The Depositary, Book-Entry and Settlement" in the Issuer's Prospectus Supplement
dated October 28, 2003 with respect to the offering of the Notes. There will be
no bearer Notes.

         Section 11.       Limitation on Transactions. If there shall have
occurred and be continuing any Event of Default, then (a) the Issuer shall not
declare or pay dividends on, or make a distribution with respect to, or redeem,
purchase or acquire, or make a liquidation payment with respect to, any of the
Issuer's capital stock (other than (i) as a result of an exchange or conversion
of any class or series of the Issuer's capital stock or rights to acquire such
capital stock for any other class or series of the Issuer's capital stock or
rights to acquire such capital stock, (ii) the purchase of fractional interests
in shares of the Issuer's capital stock pursuant to the conversion or exchange
provisions of such capital stock or the security being converted or exchanged,
(iii) dividends paid or distributions made on the Issuer's capital stock or
rights to acquire such capital stock with the Issuer's capital stock or rights
to acquire such capital stock, (iv) purchases of capital stock in connection
with the satisfaction by the Issuer of its obligations under, and in accordance
with the terms of, any of its benefit plans for its directors, officers,
employees or other persons within the definition of "employee" under any such
employee benefit plan, or (v) the repurchase or redemption of rights issued
under any shareholder rights plan) and (b) the Issuer shall not make any payment
of interest, principal or premium, if any, on or repay, repurchase or redeem any
debt securities or indebtedness for borrowed money (excluding, for the


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<PAGE>

avoidance of doubt, Senior Indebtedness, in respect of which such payments,
repayments, repurchases and redemptions may be made at any time and from time to
time) issued or incurred by the Issuer that rank PARI PASSU with or junior to
the Notes.

         Section 12.       Redemption for Changes in Canadian Tax Law. The
relevant date for purposes of Section 11.08(l)(a) and (1)(b) of the Indenture
shall be the date specified on the reverse of the Note.

         Section 13.       Savings Clause. In case of any conflict or
inconsistency between (x) the terms of this Officer's Certificate or the form of
Note set forth in Exhibit A hereto and (y) the terms of the Indenture, the terms
of this Officer's Certificate and the form of Note set forth in Exhibit A hereto
shall control and be binding.

         Section 14.       This Certificate is delivered pursuant to the
provisions of Section 3.03 of the Indenture. The undersigned hereby certifies as
follows:

         (a)      I have read each of the Sections of the Indenture referred to
above, and the definitions of the Indenture relating thereto;

         (b)      I have examined the Indenture, the form of Notes set forth in
Exhibit A hereto, and such other documents, records and instruments as I have
deemed necessary for purposes of giving this Certificate;

         (c)      in my opinion, I have made such examination and investigation
as is necessary to enable me to express an informed opinion as to whether the
conditions precedent to the issuance of the Notes have been complied with; and

         (d)      in my opinion, the conditions precedent to the issuance of the
Notes have been complied with.


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<PAGE>

         IN WITNESS WHEREOF, I have hereunto signed my name, this 4 day of
November, 2004.

                                    By: /s/ Una M. Power
                                        ---------------------------------------
                                        Name:   Una M. Power
                                        Title:  Treasurer

<PAGE>

                                                                       EXHIBIT A
                                                                       ---------

                             (FORM OF FACE OF NOTE)

         UNLESS THIS SECURITY IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (55 WATER STREET, NEW YORK,
NEW YORK) ("DTC") TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER,
EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF
CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF
DTC AND ANY PAYMENT HEREON IS MADE TO CEDE & CO. (OR AS REQUESTED BY AN
AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR
VALUE OR OTHERWISE BY A PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF,
CEDE & CO., HAS AN INTEREST HEREIN.

         THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF DTC OR A NOMINEE OF
DTC. THIS SECURITY IS EXCHANGEABLE FOR SECURITIES REGISTERED IN THE NAME OF A
PERSON OTHER THAN DTC OR ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED
IN THE INDENTURE, AND NO TRANSFER OF THIS SECURITY (OTHER THAN A TRANSFER OF
THIS SECURITY AS A WHOLE BY DTC TO A NOMINEE OF DTC OR BY A NOMINEE OF DTC TO
DTC OR ANOTHER NOMINEE OF DTC) MAY BE REGISTERED EXCEPT IN LIMITED
CIRCUMSTANCES.

NO. 001                                                        U.S. $460,000,000
                                                              CUSIP: 65334H 50 8

                                   NEXEN INC.

                  7.35% SUBORDINATED NOTES DUE NOVEMBER 1, 2043

         NEXEN INC., a corporation duly organized and subsisting under the laws
of Canada (the "Issuer", which term includes any successor corporation under the
Indenture dated as of November 4, 2003, between the Issuer and Deutsche Bank
Trust Company Americas, as Trustee (the "Trustee") (as supplemented by an
Officer's Certificate dated as of November 4, 2003 (the "Officer's
Certificate"), executed pursuant to a Board Resolution of the Issuer, the
"Indenture")), for value received, hereby promises to pay to Cede & Co., as
nominee for DTC, or its registered assigns, the principal sum of FOUR HUNDRED
SIXTY MILLION DOLLARS (U.S. $460,000,000) on November 1, 2043, and to pay
interest on said principal sum from November 4, 2003, or from the most recent
interest payment date (each such date, an "Interest Payment Date") to which
interest has been paid or duly provided for quarterly in arrears on February 1,
May 1, August 1 and November 1 of each year, commencing February 1, 2004, at the
rate of 7.35% per annum until the principal hereof shall have become due and
payable, and on any

<PAGE>

overdue principal and (to the extent that payment of such interest is
enforceable under applicable law) on any overdue installment of interest at the
same rate per annum. The amount of interest payable on any Interest Payment Date
shall be computed on the basis of a 360-day year of twelve 30-day months. For
the purpose of disclosure under the INTEREST ACT (Canada) only, each rate of
interest which is calculated with reference to a period (the "deemed interest
period") that is less than the actual number of days in the calendar year of
calculation is equivalent to a rate based on a calendar year calculated by
multiplying such rate of interest by the actual number of days in the calendar
year of calculation and dividing by the number of days in the deemed interest
period. In the event that any date on which interest is otherwise due on this
Note is not a Business Day, then payment of interest payable on such date will
be made on the next succeeding day that is a Business Day (and without any
interest or other payment in respect of any such delay), except that, if such
Business Day is in the next succeeding calendar year, such payment shall be made
on the immediately preceding Business Day, in each case with the same force and
effect as if made on such date. The interest installment so payable, and
punctually paid or duly provided for, on any Interest Payment Date, as provided
in the Indenture, will be paid to the Person in whose name this Note (or one or
more predecessor Notes) is registered at the close of business on the Record
Date for such interest installment, which shall be the January 15, April 15,
July 15 or October 15, as the case may be, immediately preceding such Interest
Payment Date. Any such interest installment not punctually paid or duly provided
for shall forthwith cease to be payable to the registered Holders on such Record
Date and may be paid to the Person in whose name this Note (or one or more
predecessor Notes) is registered at the close of business on a Special Record
Date to be fixed by the Trustee for the payment of such defaulted interest,
notice whereof shall be given to the registered Holders of this Note not less
than 10 days prior to such Special Record Date, or may be paid at any time in
any other lawful manner not inconsistent with the requirements of any securities
exchange on which the Notes may be listed, and upon such notice as may be
required by such exchange, all as more fully provided in the Indenture. The
principal of and the interest on this Note shall be payable at the office or
agency of the Trustee maintained for that purpose in U.S. Dollars; PROVIDED,
HOWEVER, that payment of interest may be made at the option of the Issuer by
mailing a check payable to the Holder at such address as it appears on the
Security Register or wire transfer to an account maintained by the payee located
in the U.S. Notwithstanding the foregoing, a Holder of U.S.$5.0 million or more
in aggregate principal amount of Notes will be entitled to receive interest
payments, if any, on any Interest Payment Date other than the Maturity by wire
transfer of immediately available funds if appropriate wire transfer
instructions have been received in writing by the Trustee not less than 15 days
prior to such Interest Payment Date. Any such wire transfer instructions
received by the Trustee shall remain in effect until revoked by such Holder.

         The Issuer may pay the Redemption Price or the Maturity Amount of the
Notes at Maturity by making a Common Shares Payment Election in accordance with
Section 6 of the Officer's Certificate, in which event the Holder of this Note
shall be entitled to receive payments in cash equal to such Redemption Price or
Maturity Amount from funds resulting from the sale of the requisite number of
Common Shares and any U.S. Government Obligations purchased with such funds, as
set forth in the Indenture.

         The indebtedness evidenced by this Note is, to the extent provided in
the Indenture, subordinate and junior in right of payment to all Senior
Indebtedness and this Note is issued subject to the provisions of the Indenture
with respect thereto. Each Holder of this Note, by


                                        2
<PAGE>

accepting the same, (a) agrees to and shall be bound by all the provisions of
the Indenture, (b) authorizes and directs the Trustee on his or her or its
behalf to take such action as may be necessary or appropriate to acknowledge or
effectuate the subordination so provided and (c) irrevocably appoints the
Trustee his or her or its attorney-in-fact for any and all such purposes. Each
Holder hereof, by his or her or its acceptance hereof, hereby waives all notice
of the acceptance of the subordination provisions contained herein and in the
Indenture by each holder of Senior Indebtedness, whether now outstanding or
hereafter incurred, and waives reliance by each such Holder upon said
provisions.

         This Note shall not be entitled to any benefit under the Indenture, be
valid or become obligatory for any purpose until this Note has been
authenticated by the Trustee in accordance with Section 2.02 of the Indenture.

         The provisions of this Note are continued on the reverse side hereof
and such continued provisions shall for all purposes have the same effect as
though fully set forth at this place.


                                        3
<PAGE>

         IN WITNESS WHEREOF, the Issuer has caused this instrument to be
executed.


Dated as of November 4, 2003.       NEXEN INC.

                                    By: _______________________________________
                                        Name:
                                        Title:


                                    By: _______________________________________
                                        Name:
                                        Title:


         This is one of the Securities referred to in the within-mentioned
Indenture.

                                    DEUTSCHE BANK TRUST COMPANY
                                    AMERICAS, as Trustee


                                    By: _______________________________________
                                        Authorized Signatory

<PAGE>

                          (FORM OF REVERSE OF SECURITY)

         This Security is one of a duly authorized issue of securities of the
Issuer designated as its 7.35% Subordinated Notes due 2043 (hereinafter the
"Notes"), limited to the aggregate principal amount of U.S.$460,000,000, which
amount includes the exercise of the Over-Allotment Option issued under and
pursuant to the Indenture, to which the Indenture and all indentures
supplemental thereto reference is hereby made for a description of the rights,
limitations of rights, obligations, duties and immunities thereunder of the
Trustee, the Issuer and the Holders. The terms of the Notes include those stated
in the Indenture and those made part of the Indenture by reference to the Trust
Indenture Act. The Notes are subject to all such terms, and Holders are referred
to the Indenture and the Trust Indenture Act for a statement of such terms.

         The Issuer shall have the right, from time to time, without the consent
of the Holders of the Notes, to issue additional Securities under the Indenture.

         The Issuer shall have the right to redeem this Note at its option, in
whole or in part, at any time on or after November 4, 2008 at a Redemption Price
equal to 100% of the principal amount thereof plus accrued and unpaid interest
thereon to the Redemption Date.

         If the Notes are only partially redeemed by the Issuer, the Notes will
be redeemed PRO RATA or by lot or by any other method utilized by the Trustee;
PROVIDED that if, at the time of redemption, the Notes are registered as a
Global Note, DTC shall determine the principal amount of such Notes owned by
each beneficial owner to be redeemed in accordance with its procedures.

         In the event of redemption of this Note in part only, a new Note or
Notes for the unredeemed portion hereof will be issued in the name of the Holder
hereof upon the surrender and cancellation hereof.

         The Issuer shall have the right to redeem, at any time, the Securities
of a series, in whole but not in part, at a redemption price equal to the
principal amount thereof together with accrued and unpaid interest to the date
fixed for redemption, upon the giving of a notice as described below, if (1) the
Issuer determines that (a) as a result of any change in or amendment to the laws
(or any regulations or rulings promulgated thereunder) of Canada or the
Applicable Jurisdiction or of any political subdivision or taxing authority
thereof or therein affecting taxation, or any change in the official position
regarding the application or interpretation of such laws, regulations or rulings
(including a holding by a court of competent jurisdiction), which change or
amendment is announced or becomes effective on or after October 28, 2003, in the
case of Additional Amounts or, in the case of Reorganization Additional Amounts,
on or after the date on which the Issuer becomes subject to the laws of the
Applicable Jurisdiction, the Issuer has or will become obligated to pay, on the
next succeeding date on which interest is due, Additional Amounts pursuant to
Section 10.05 of the Indenture or Reorganization Additional Amounts pursuant to
Section 8.03 of the Indenture or there is more than an insubstantial risk that
the Issuer could be denied the deduction of interest paid or payable in respect
of the Securities in computing the Issuer's income for the purposes of the
INCOME TAX ACT (Canada) or a Canadian provincial or territorial income tax
statute, or (b) on or after October 28, 2003, in the case of Additional Amounts
or, in the case of Reorganization Additional Amounts, on or after the date on
which the Issuer becomes subject to the laws of the Applicable Jurisdiction, any
action has

<PAGE>

been taken by any taxing authority of, or any decision has been rendered by a
court of competent jurisdiction in, Canada or the Applicable Jurisdiction or any
political subdivision or taxing authority thereof or therein, including any of
those actions specified in (a) above, whether or not such action was taken or
decision was rendered with respect to the Issuer, or any change, amendment,
application or interpretation shall be officially proposed, which, in any such
case, in the Opinion of Counsel to the Issuer, will result in the Issuer
becoming obligated to pay, on the next succeeding date on which interest is due,
Additional Amounts or Reorganization Additional Amounts with respect to any Note
of such series or there is more than an insubstantial risk that the Issuer could
be denied the deduction of interest paid or payable in respect of the Securities
in computing the Issuer's income for the purposes of the INCOME TAX ACT (Canada)
or a Canadian provincial or territorial income tax statute, and (2) in any such
case, the Issuer in its business judgment determines that any such obligation
under paragraph (1) above cannot be avoided by the use of reasonable measures
available to the Issuer; PROVIDED, however, that (i) no such notice of
redemption may be given earlier than 60 nor later than 30 days prior to the
earliest date on which the Issuer would be obligated to pay such Additional
Amounts or Reorganization Additional Amounts were a payment in respect of the
Securities then due or on which the Issuer would be denied the deduction of
interest paid or payable in respect of the Securities, and (ii) at the time such
notice of redemption is given, such obligation to pay such Additional Amounts or
Reorganization Additional Amounts or such denial of the deductibility of
interest remains in effect. The Redemption Price is payable in cash or, at the
option of the Issuer, by delivery of Common Shares to the Trustee pursuant to
Section 6 of the Officer's Certificate. The Redemption Price shall be paid prior
to 12:00 noon, New York City time, on the date of such redemption or at such
earlier time as the Issuer determines; PROVIDED that the Issuer shall deposit
with the Trustee an amount in cash or Common Shares in accordance with Section 6
of the Officer's Certificate sufficient to pay the Redemption Price on the date
such Redemption Price is to be paid.

         In case an Event of Default, as defined in the Indenture, shall have
occurred and be continuing, the principal of all of the Notes may be declared,
and upon such declaration shall become, due and payable in the manner, with the
effect and subject to the conditions provided in the Indenture.

         The Indenture contains provisions permitting the Issuer and the
Trustee, with the consent of the Holders of not less than a majority in
principal amount of the Outstanding Notes, to execute supplemental indentures
for the purpose of adding any provisions to or changing in any manner or
eliminating any of the provisions of the Indenture or of any supplemental
indenture or of modifying in any manner the rights of the Holders; PROVIDED,
HOWEVER, that no such supplemental indenture shall, without the consent of the
Holder of each Outstanding Note, (i) change the Stated Maturity of the principal
of, or premium, other amounts, if any, or any installment of principal of or
premium, other amounts, if any, or interest on, any Note, or reduce the
principal amount (or accreted value, as the case may be) thereof or the rate of
interest thereon or accretions or any premium or other amounts payable upon the
redemption, repurchase or repayment thereof, or change the manner in which the
amount of any of the foregoing is determined, or reduce the amount of the
principal (or accreted value, as the case may be) that would be due and payable
upon a declaration of acceleration of the Maturity thereof pursuant to Section
5.02 of the Indenture, or change any Place of Payment where, or the Applicable
Currency for, or impair the right to receive, payment of the principal of or
premium, interest or


                                        2
<PAGE>

other amounts, if any, on any Holder's Notes on or after their respective due
dates or to institute suit for the enforcement of any such payment; (ii) reduce
the percentage in principal amount of the Outstanding Notes, the consent of
whose Holders is required for any such supplemental indenture, or the consent of
whose Holders is required for any waiver of compliance with certain provisions
of the Indenture or Defaults or Events of Default thereunder and their
consequences provided for in the Indenture; (iii) modify any of the provisions
of Section 9.02, Section 5.07, Section 5.13 or Section 10.06 of the Indenture,
except to increase any such percentage or to provide that certain other
provisions of the Indenture cannot be modified or waived without the consent of
the Holder of each Outstanding Note affected thereby; PROVIDED, HOWEVER, that
this clause shall not be deemed to require the consent of any Holder with
respect to changes in the references to "the Trustee" and concomitant changes in
Sections 9.02 and 10.06 of the Indenture, or the deletion of the proviso in
Section 9.02(3), in accordance with the requirements of Sections 6.11(b) and
9.01(8) of the Indenture; (iv) modify any conversion ratio or otherwise impair
conversion rights with respect to the Outstanding Notes; (v) modify the
redemption provisions applicable to the Outstanding Notes; (vi) directly or
indirectly release any of the collateral or security interest in respect of the
Outstanding Notes; (vii) modify the subordination provisions applicable to the
Notes or the definition of "Senior Indebtedness" in a manner adverse to the
Holders of the Notes; or (viii) change any obligations to pay additional amounts
provided in the terms of the Outstanding Notes. The Indenture also contains
provisions permitting the Holders of a majority in principal amount of the
Outstanding Notes, on behalf of the Holders of all the Notes, to waive any past
default described in Section 5.01 of the Indenture, and its consequences, except
(i) a default in respect of the payment of the principal of or premium, other
amounts, if any, or interest on the Notes or (ii) a default in respect of a
covenant of the Issuer or a provision of the Indenture that under the Indenture
may not be modified or amended without the consent of the Holder of each
Outstanding Note. Any such consent or waiver by the registered Holder of this
Note (unless revoked as provided in the Indenture) shall be conclusive and
binding upon such Holder and upon all future Holders and owners of this Note and
of any Note issued in exchange therefor or in place hereof (whether by
registration of transfer or otherwise), irrespective of whether or not any
notation of such consent or waiver is made upon this Note.

         No reference herein to the Indenture and no provision of this Note or
of the Indenture shall alter or impair the obligation of the Issuer, which is
absolute and unconditional, to pay the principal of and interest on this Note at
the time and place and at the rate and in the money herein prescribed.

         The Issuer may pay the Maturity Amount or the Redemption Price at
Maturity by making a Common Shares Payment Election and delivering Common Shares
to the Trustee for sale, the proceeds of which shall be deposited in the
Property Account and/or invested in U.S. Government Obligations for the payment
of the Maturity Amount or the Redemption Price at Maturity, all in accordance
with Section 6 of the Officer's Certificate. The Trustee shall, from funds
received from such U.S. Government Obligations, together with funds in the
Property Account, pay the Maturity Amount at Stated Maturity or the Redemption
Price at the Redemption Date to the Holders entitled thereto.

         As provided in the Indenture and subject to certain limitations therein
set forth, this Note is transferable by the registered Holder hereof on the
Security Register of the Issuer, upon surrender of this Note for registration of
transfer at the office or agency of the Trustee in the


                                        3
<PAGE>

Borough of Manhattan in the City and State of New York accompanied by a written
instrument or instruments of transfer in form satisfactory to the Issuer and the
Trustee duly executed by the registered Holder hereof or its attorney duly
authorized in writing, and thereupon one or more new Notes of authorized
denominations and for the same aggregate principal amount will be issued to the
designated transferee or transferees. No service charge will be made for any
such transfer, but the Issuer may require payment of a sum sufficient to cover
any tax or other governmental charge payable in relation thereto.

         Prior to due presentment for registration of transfer of this Note, the
Issuer, the Trustee, any Paying Agent and the Security Registrar may deem and
treat the registered Holder hereof as the absolute owner hereof (whether or not
this Note shall be overdue and notwithstanding any notice of ownership or
writing hereon made by anyone other than the Security Registrar) for the purpose
of receiving payment of or on account of the principal hereof and interest due
hereon and for all other purposes, and neither the Issuer nor the Trustee nor
any Paying Agent nor any Security Registrar shall be affected by any notice to
the contrary.

         No recourse shall be had for the payment of the principal or the
interest on this Note, or for any claim based hereon, or otherwise in respect
hereof, or based on or in respect of the Indenture, against any incorporator,
stockholder, officer or director, past, present or future, as such, of the
Issuer or of any predecessor or successor corporation, whether by virtue of any
constitution, statute or rule of law, or by the enforcement of any assessment or
penalty or otherwise, all such liability being, by the acceptance hereof and as
part of the consideration for the issuance hereof, expressly waived and
released.

         The Notes are issuable only in registered form without coupons in
denominations of U.S.$25 and any integral multiple thereof. This Global Note is
exchangeable for Notes in definitive form only under certain limited
circumstances set forth in the Indenture. As provided in the Indenture and
subject to certain limitations herein and therein set forth, Notes so issued are
exchangeable for a like aggregate principal amount of Notes of a different
authorized denomination, as requested by the Holder surrendering the same.

         The Indenture and this Note shall be governed by and construed in
accordance with the laws of the State of New York.

         All terms used in this Note that are defined in the Indenture shall
have the meanings assigned to them in the Indenture, unless otherwise defined
herein.


                                        4