UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549



                                  FORM 8-A12B/A

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934



                               ENCANA CORPORATION
             (Exact name of registrant as specified in its charter)

              CANADA                                            98-0355077
(State or other jurisdiction of                              (I.R.S. Employer
 incorporation or organization)                              Identification No.)


1800 - 855 2ND STREET, S.W., P.O. BOX 2850, CALGARY, ALBERTA      T2P 2S5
(Address of principal executive offices)                         (Zip Code)

If this form relates to the registration of a class of securities pursuant to
Section 12(b) of the Exchange Act and is effective pursuant to General
Instruction A.(c), check the following box. [X]

If this form relates to the registration of a class of securities pursuant to
Section 12(g) of the Exchange Act and is effective pursuant to General
Instruction A.(d), check the following box. [_]

Securities Act registration file number to which this form relates
(if applicable):

Securities to be registered pursuant to Section 12(g) of the Act:  None


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                 INFORMATION REQUIRED IN REGISTRATION STATEMENT


EXPLANATORY NOTE

PanCanadian Energy Corporation (as EnCana Corporation ("EnCana") was then named)
adopted a shareholder rights plan effective July 30, 2001, as amended and
restated as of September 13, 2001 (the "Rights Plan"). The Rights Plan was
approved by the shareholders of PanCanadian Energy Corporation at a special
meeting of shareholders held on September 26, 2001, as required by the Toronto
Stock Exchange.

On April 28, 2004, holders of common shares of EnCana approved an ordinary
resolution to amend and reconfirm the Rights Plan. The matter was put to a vote
by ballot, which includes votes cast in person and by proxy, with 94.5% of the
votes cast in favor.

EnCana therefore amends Items 1 and 2 of its Registration Statement on Form 8-A,
as filed with the Securities and Exchange Commission on August 16, 2001, and
amended on October 17, 2001.

ITEM 1.  DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED.

PURPOSE OF RIGHTS PLAN

The primary objective of a rights plan is to provide the board of directors of
EnCana (the "Board") with sufficient time to explore and develop all options for
maximizing shareholder value if a take-over bid is made for EnCana and to
provide every shareholder with an equal opportunity to participate in such a
bid. The Rights Plan encourages a potential acquiror to proceed either by way of
a Permitted Bid (as defined therein), which requires the take-over bid to
satisfy certain minimum standards designed to promote fairness, or with the
concurrence of the Board.

SUMMARY OF RIGHTS PLAN

The terms of the Rights Plan as amended conform to the terms of plans now in
place in many other Canadian public companies and reflect recommendations
received from professional commentators on shareholder rights plans.

         TERM

The term of the Rights Plan expires 10 years from July 30, 2001, subject to the
shareholders reconfirming such plan by a majority vote at every third annual
meeting of EnCana after its annual meeting in 2001. On this basis, the Rights
Plan was presented at this year's annual meeting and will be considered again at
the EnCana annual meetings in 2007 and 2010 for reconfirmation. If any such
approval is not obtained, the Rights Plan will then cease to have effect.

         ISSUE OF RIGHTS

On the effective date of the Rights Plan, one right ("Right") was issued and
attached to each common share and will attach to each common share subsequently
issued.


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         RIGHTS EXERCISE PRIVILEGE

The Rights will separate from the common shares and will be exercisable 10
trading days (the "Separation Time") after a person has acquired, or commenced a
take-over bid to acquire, 20 percent or more of the common shares, other than by
an acquisition pursuant to a take-over bid permitted by the Rights Plan (a
"Permitted Bid"). The acquisition by any person (an "Acquiring Person") of 20
percent or more of the common shares, other than by way of a Permitted Bid is
referred to as a "Flip-in Event". Any Rights held by an Acquiring Person will
become void upon the occurrence of a Flip-in Event. Ten trading days after the
occurrence of the Flip-in Event, each Right (other than those held by an
Acquiring Person), will permit the purchase by holders of Rights (other than an
Acquiring Person) of common shares at a 50 percent discount to their market
price. The issue of the Rights is not initially dilutive. Upon a Flip-in Event
occurring and the Rights separating from the common shares, reported earnings
per share of EnCana on a diluted or non-diluted basis may be affected. Holders
of Rights not exercising their Rights upon the occurrence of a Flip-in Event may
suffer substantial dilution.

         LOCK-UP AGREEMENTS

A bidder may enter into lock-up agreements with shareholders whereby such
shareholders agree to tender their common shares to the take-over bid (the
"Subject Bid") without a Flip-in Event (as referred to above) occurring. Any
such agreement must permit the shareholder to withdraw the common shares to
tender to another take-over bid or to support another transaction that exceeds
the value of the Subject Bid by as much or more than a specified amount, which
specified amount may not be greater than 7 percent. As discussed below, the
definition of "Lock-Up Agreement" was amended to provide that no "break up" fees
or other penalties exceeding the thresholds described below be payable under
such agreements.

         CERTIFICATES AND TRANSFERABILITY

Prior to the Separation Time, the Rights are evidenced by a legend imprinted on
certificates for the common shares and are not to be transferable separately
from the common shares. From and after the Separation Time, the Rights will be
evidenced by Rights certificates, which will be transferable and traded
separately from the common shares.

         PERMITTED BID REQUIREMENTS

The requirements for a Permitted Bid include the following:

         o  the take-over bid must be made by way of a take-over bid circular;

         o  the take-over bid must be made to all holders of common shares;

         o  the take-over bid must be outstanding for a minimum period of 60
            days and common shares tendered pursuant to the take-over bid may
            not be taken up prior to the expiry of the 60 day period and only if
            at such time more than 50 percent of the common shares held by
            Independent Shareholders have been tendered to the take-over bid and
            not withdrawn; and

         o  if more than 50 percent of the common shares held by Independent
            Shareholders are tendered to the take-over bid within the 60 day
            period, the bidder must make a public announcement of that fact and
            the take-over bid must remain open for deposits of



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            common shares for not less than 10 business days from the date of
            such public announcement.

The Rights Plan allows for a competing Permitted Bid (a "Competing Permitted
Bid") to be made while a Permitted Bid is in existence. A Competing Permitted
Bid must satisfy all the requirements of a Permitted Bid except that it may
expire on the same date as the Permitted Bid, subject to the requirement that it
be outstanding for a minimum period of 35 days.

         WAIVER

The Board, acting in good faith, may, prior to the occurrence of a Flip-in
Event, waive the application of the Rights Plan to a particular Flip-in Event
(an "Exempt Acquisition") where the take-over bid is made by a take-over bid
circular to all holders of common shares. Where the Board exercises the waiver
power for one take-over bid, the waiver will also apply to any other take-over
bid for the Corporation made by a take-over bid circular to all holders of
common shares prior to the expiry of any other bid for which the Rights Plan has
been waived.

         REDEMPTION

The Board with the approval of a majority of votes cast by the Independent
Shareholders (or the holders of Rights if the Separation Time has occurred)
voting in person or by proxy at a meeting duly called for that purpose may
redeem the Rights at $0.000001 per common Share. Rights will be deemed to have
been redeemed by the Board following completion of a Permitted Bid, Competing
Permitted Bid or Exempt Acquisition.

         AMENDMENT

The Board may amend the Rights Plan with the approval of a majority of the votes
cast by Independent Shareholders (or the holders of Rights if the Separation
Time has occurred) voting in person or by proxy at a meeting duly called for
that purpose. The Board without such approval may correct clerical or
typographical errors and, subject to approval as noted above at the next meeting
of the holders of common shares (or the holders of Rights, as the case may be),
may make amendments to the Rights Plan to maintain its validity due to changes
in applicable legislation.

         BOARD

The Rights Plan will not detract from or lessen the duty of the Board to act
honestly and in good faith with a view to the best interests of EnCana. The
EnCana Board, when a Permitted Bid is made, will continue to have the duty and
power to take such actions and make such recommendations to shareholders as are
considered appropriate.

         EXEMPTION FOR INVESTMENT MANAGERS

Investment managers (for client accounts), trust companies (acting in their
capacities as trustees and administrators), statutory bodies whose business
includes the management of funds and administrators of registered pension plans
acquiring greater than 20 percent of the common shares are exempted from
triggering a Flip-in Event, provided that they are not making, or are not part
of a group making, a take-over bid.


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TECHNICAL AMENDMENTS TO RIGHTS PLAN

On April 28, 2004, EnCana shareholders voted to approve the following technical
amendments to the Rights Plan in order to update and restate the Rights Plan and
conform the terms of the Rights Plan to plans now in place in many other
Canadian public companies. Certain changes also reflect recommendations received
from professional commentators on shareholder rights plans. The amendments to
the Rights Plan were effective as of April 28, 2004 and include:

         o  amending the definition of "Lock-Up Agreement" referred to above to
            provide that no "break up" fees or other penalties that exceed in
            the aggregate the greater of 2.5 percent of the price or value of
            the consideration payable under the Subject Bid (as referred to
            above) and 50 percent of the increase in the consideration resulting
            from another take-over bid or transaction shall be payable by the
            shareholder if the shareholder fails to tender its common shares to
            the Subject Bid; and

         o  adding a requirement that the Rights Plan can only be amended with
            the approval of the holders of common shares or Rights, if the Board
            determines that, in the case of a stock dividend or the issuance of
            common shares or other securities of the Corporation in exchange for
            existing common shares in transactions not otherwise addressed by
            the anti-dilution provisions of the Rights Plan, other adjustments
            would be required to the exercise price, number of Rights and/or
            securities purchasable upon exercise of Rights in order to
            appropriately protect the interests of the holders of the Rights in
            such cases.



ITEM 2.  EXHIBITS.

         EXHIBIT NUMBER                     DESCRIPTION OF EXHIBIT
--------------------------------------------------------------------------------
              4.1                 Amendment to the Amended and Restated
                                  Shareholder Rights Plan Agreement dated as of
                                  April 28, 2004 between EnCana Corporation and
                                  CIBC Mellon Trust Company, as Rights Agent,
                                  which includes the Form of Rights Certificate
                                  as ATTACHMENT 1



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                                    SIGNATURE


         Pursuant to the requirements of Section 12 of the Securities Exchange
Act of 1934, the Registrant has duly caused this registration statement to be
signed on its behalf by the undersigned, thereto duly authorized.

Dated:  June 30, 2004

                                            ENCANA CORPORATION


                                            By: /s/ Kerry D. Dyte
                                                ---------------------
                                                Name:  Kerry D. Dyte
                                                Title: General Counsel &
                                                       Corporate Secretary



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                                INDEX TO EXHIBITS


         EXHIBIT NUMBER                     DESCRIPTION OF EXHIBIT
--------------------------------------------------------------------------------
              4.1                 Amendment to the Amended and Restated
                                  Shareholder Rights Plan Agreement dated as of
                                  April 28, 2004 between EnCana Corporation and
                                  CIBC Mellon Trust Company, as Rights Agent,
                                  which includes the Form of Rights Certificate
                                  as ATTACHMENT 1