EXHIBIT 99.1

THE INFORMATION IN THIS PROSPECTUS SUPPLEMENT IS NOT COMPLETE AND MAY BE
CHANGED. THIS PROSPECTUS SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS ARE NOT AN
OFFER TO SELL THESE SECURITIES AND THEY ARE NOT SOLICITING AN OFFER TO BUY THESE
SECURITIES IN ANY JURISDICTION WHERE THE OFFER OR SALE IS NOT PERMITTED.


PROSPECTUS SUPPLEMENT (Subject to Completion) Issued January 13, 2003

(To Prospectus dated March 30, 2000)

                                6,200,000 Shares

                           [Apache Corporation LOGO]

                                  COMMON STOCK

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

APACHE CORPORATION IS OFFERING 6,200,000 SHARES OF ITS COMMON STOCK.

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

OUR COMMON STOCK IS LISTED ON THE NEW YORK STOCK EXCHANGE AND THE CHICAGO STOCK
EXCHANGE UNDER THE SYMBOL "APA." ON JANUARY 10, 2003, THE LAST REPORTED SALE
PRICE OF OUR COMMON STOCK ON THE NEW YORK STOCK EXCHANGE WAS $56.60 PER SHARE.

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

INVESTING IN OUR COMMON STOCK INVOLVES RISKS. SEE "RISK FACTORS" BEGINNING ON
PAGE S-7 OF THIS PROSPECTUS SUPPLEMENT.

                            ------------------------
                              PRICE $      A SHARE
                            ------------------------

<Table>
<Caption>
                                                                  UNDERWRITING
                                                       PRICE TO   DISCOUNTS AND   PROCEEDS TO
                                                        PUBLIC     COMMISSIONS      APACHE
                                                       --------   -------------   -----------
                                                                         
Per Share............................................     $            $              $
Total................................................  $            $              $
</Table>

Apache Corporation has granted the underwriters the right to purchase up to an
additional 930,000 shares to cover over-allotments.

The Securities and Exchange Commission and state securities regulators have not
approved or disapproved of these securities, or determined if this prospectus
supplement or the accompanying prospectus is truthful or complete. Any
representation to the contrary is a criminal offense.

The underwriters expect to deliver the shares to purchasers on January   , 2003.

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

MORGAN STANLEY
                    SALOMON SMITH BARNEY
                                             RBC CAPITAL MARKETS

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

ROBERT W. BAIRD & CO.
                  A.G. EDWARDS & SONS, INC.
                                     PETRIE PARKMAN & CO.
                                                   RAYMOND JAMES
January   , 2003


                          [APACHE CORPORATION CHARTS]


     These charts reflect our estimated production before and after the pending
BP transactions by core areas. Percentages are calculated by using Apache's
January 2003 estimated daily production rate and our estimate of the daily
production rate from the BP assets for 2003, which we used to value the assets
that we have agreed to acquire. The estimated production attributable to the
pending BP transactions is based solely on our internal estimates and has not
been reviewed by our independent reserve engineers. There is no assurance that
the pending BP transactions will be completed or that our estimate of production
will prove correct.

                               OIL AND GAS TERMS

<Table>
                                                
When describing natural gas:........   Mcf            = thousand cubic feet
                                       MMbtu          = million British thermal units
                                       MMcf           = million cubic feet
                                       Bcf            = billion cubic feet
When describing oil:................   Bbl            = barrel
                                       Mbbls          = thousand barrels
                                       MMbbls         = million barrels
When comparing natural gas to
  oil:..............................   6 Mcf of gas   = 1 bbl of oil equivalent
                                       Boe            = barrel of oil equivalent
                                       Mboe           = thousand barrels of oil equivalent
                                       MMboe          = million barrels of oil equivalent
</Table>

                                        i


                               TABLE OF CONTENTS

<Table>
<Caption>
                                        PAGE
                                        ----
                                     
           PROSPECTUS SUPPLEMENT
Oil and Gas Terms.....................     i
About this Prospectus Supplement......    ii
Prospectus Supplement Summary.........   S-1
Risk Factors..........................   S-7
Special Note Regarding Forward-Looking
  Statements..........................  S-12
Use of Proceeds.......................  S-13
Capitalization........................  S-14
Price Range of Common Stock...........  S-15
Dividend Policy.......................  S-15
Material U.S. Federal Tax Consequences
  to Non-U.S. Holders of Common
  Stock...............................  S-16
Underwriting..........................  S-19
Legal Matters.........................  S-21
Experts...............................  S-21
Where You Can Find More Information
  About the Company...................  S-22
</Table>

<Table>
<Caption>
                                        PAGE
                                        ----
                                     
                 PROSPECTUS
About This Prospectus.................     1
Where You Can Find More Information...     1
Cautionary Statements Regarding
  Forward-Looking Statements..........     3
Apache Corporation....................     3
Apache Trusts.........................     3
Ratios of Earnings to Fixed Charges
  and to Combined Fixed Charges and
  Preferred Stock Dividends...........     4
Use of Proceeds.......................     5
The Securities Apache and the Apache
  Trusts May Offer....................     5
Description of Capital Stock..........     7
Description of Depositary Shares......    15
Description of Debt Securities........    18
Description of Trust Preferred
  Securities..........................    32
Description of Trust Preferred
  Securities Guarantees...............    38
Description of Common Stock Purchase
  Contracts and Units.................    41
Book-Entry Securities.................    41
Plan of Distribution..................    43
Legal Matters.........................    44
Experts...............................    44
</Table>

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

                        ABOUT THIS PROSPECTUS SUPPLEMENT

     This document is in two parts. The first part is this prospectus
supplement, which describes the terms of the offering of common stock. The
second part is the accompanying prospectus, which contains a description of the
common stock and gives more general information, some of which may not apply to
the common stock.

     You should rely only on the information contained in or incorporated by
reference in this prospectus supplement and the accompanying prospectus. If the
information in this prospectus supplement varies from the information contained
or incorporated by reference in the accompanying prospectus, you should rely on
the information in this prospectus supplement. No person is authorized to
provide you with different information or to offer the common stock in any
jurisdiction where the offer is not permitted. You should not assume that the
information provided by this prospectus supplement, the accompanying prospectus
or in any document incorporated by reference is accurate as of any date other
than the date of the document that contains the information.

                                        ii


                         PROSPECTUS SUPPLEMENT SUMMARY

     This summary highlights selected information about us and this offering.
This summary is not complete and does not contain all of the information that is
important to you. You should carefully read this prospectus supplement, the
accompanying prospectus and the other documents we refer to and incorporate by
reference for a more complete understanding of us and this offering. In
particular, we incorporate important business and financial information in this
prospectus supplement and the accompanying prospectus by reference. Unless
otherwise indicated, all information in this prospectus supplement assumes that
the underwriters do not exercise their over-allotment option. Unless otherwise
stated, the dollar amounts and financial data contained in this prospectus
supplement and the accompanying prospectus are presented in U.S. dollars.

     Unless this prospectus supplement otherwise indicates or the context
otherwise requires, the terms "we," "our," "us" or "Apache" as used in this
prospectus supplement refer to Apache Corporation.

                               APACHE CORPORATION

     Apache Corporation is an independent energy company that, directly and
through subsidiaries, explores for, acquires and develops oil and gas reserves
and produces natural gas, crude oil, condensate and natural gas liquids. In
North America, our exploration and production interests are focused on the Gulf
of Mexico, the Anadarko Basin, the Permian Basin, the Gulf Coast and the Western
Sedimentary Basin of Canada. Outside North America, we currently have
exploration and production interests offshore Western Australia, Argentina and
in Egypt and exploration interests in Poland and offshore The People's Republic
of China.

     Through September 30, 2002, our average daily production was:

      --   162 Mbbls of crude oil, condensate and natural gas liquids; and

      --   1,082 MMcf of natural gas.

     As of December 31, 2001, our worldwide proved reserves totaled 1,267 MMboe,
including:

      --   599 MMbbls of crude oil, condensate and natural gas liquids; and

      --   4,005 Bcf of natural gas.

STRATEGY

     Our strategy is to increase our oil and gas reserves, production, cash flow
and earnings through a balanced growth program that involves:

      --   exploiting our existing asset base;

      --   acquiring properties to which we can add incremental value; and

      --   investing in high-potential exploration prospects.

     Exploiting Our Existing Asset Base.  We seek to maximize the value of our
existing asset base by increasing production and reserves while controlling per
unit operating costs. In order to achieve these objectives, we rigorously
examine our operations to reduce costs, identify production enhancement
initiatives such as workovers and recompletions employing new technology, and
divest marginal and non-strategic properties.

     Acquiring Properties To Which We Can Add Incremental Value.  Generally, we
seek to purchase reserves at appropriate prices by avoiding auction processes
where we are competing with other buyers and timing our acquisitions to avoid
the peak of the price cycle. Our aim is to follow each acquisition with a cycle
of reserve enhancement, property consolidation and cash flow acceleration,
thereby facilitating asset growth and debt reduction. During the past decade, we
have consistently succeeded in adding value to acquired properties through this
strategy. We made acquisitions totaling $1.4 billion, $1.2 billion and
approximately $355 million, and acquired proved reserves of 253.8 MMboe, 212.6
MMboe and approximately 50 MMboe, in 2000, 2001 and 2002, respectively. We
believe that the current environment is favorable for possible additional
acquisitions. We continue to evaluate attractive opportunities. Any future
acquisitions would be subject to a

                                       S-1


number of conditions, including conditions beyond our control, and there can be
no assurance that we will enter into or actually consummate any such
transactions.

     Investing In High-Potential Exploration Prospects.  Our international
investments and exploration activities are a significant component of our
long-term growth strategy. They complement our North American operations, which
are more development oriented. We seek to concentrate our exploratory
investments in a select number of international areas and to become a dominant
operator in those regions. We believe that these investments, although
higher-risk, offer the potential for significant reserve additions.

     A critical component in implementing our three-pronged growth strategy is
maintenance of significant financial flexibility. We are committed to preserving
a strong balance sheet and credit position to give us the foundation required to
pursue our growth initiatives.

RECENT DEVELOPMENTS

     Pending Transactions with BP p.l.c.  On January 11, 2003, we signed two
purchase and sales agreements with subsidiaries of BP p.l.c., which we refer to
collectively as "BP," to purchase their interests in 61 producing fields,
including 113 blocks in the Gulf of Mexico and two producing fields in the North
Sea. We will operate 36 of the producing fields in the Gulf of Mexico and both
of the producing fields in the North Sea.

     Each of the purchase agreements is effective as of January 1, 2003. We
anticipate the purchase of the Gulf of Mexico properties will close late in the
first quarter of 2003, and the purchase of the North Sea properties will close
late in the second quarter of 2003. The total purchase price for all of the
assets being acquired is $1.3 billion, with $670 million allocated to the
purchase of the Gulf of Mexico assets and $630 million allocated to the North
Sea assets. The actual price payable upon the closing of each purchase will be
reduced by the net cash flow attributable to the acquired fields, and increased
by interest on the purchase price, from January 1, 2003, until the date of
closing. The purchase price will also be subject to customary closing
adjustments. Owners of working interests in certain Gulf of Mexico properties
have preferential purchase rights which, if exercised, would reduce the
interests we purchase in those properties and the purchase price we would pay.
Neither acquisition is conditional upon the consummation of the other
acquisition.

     The properties we are acquiring from BP in the Gulf of Mexico complement
our extensive existing reserves and production in the Gulf, while the North Sea
properties establish a new core area for us. Of the Gulf of Mexico properties we
will acquire, most of the working interests exceed 50 percent, 19 of the fields
are owned 100 percent and approximately 70 percent of the production will be
operated by us. We are acquiring a 96 percent working interest in, and will be
the operator of, the North Sea properties.

     We estimate that the properties we will acquire in the BP transactions had
proved reserves as of January 1, 2003 of:

      --   186.5 MMbbls of crude oil and natural gas liquids; and

      --   279.9 Bcf of natural gas.

     Using the conventional equivalence of one barrel of oil to six Mcf of gas,
these estimated proved reserves totaled 233.2 MMboe and were approximately 80
percent oil and 20 percent gas. Approximately 93 percent of these estimated
proved reserves are developed reserves. We also estimate that 21 percent of the
total oil reserves and 100 percent of the reserves of natural gas are in the
Gulf of Mexico properties.

     The 2003 production estimates used to value the acquisition were:

      --   65.5 Mbbls per day of crude oil and natural gas liquids; and

      --   197.6 MMcf per day of natural gas.

                                       S-2


     The estimates mentioned in the preceding three paragraphs are based on our
analysis of historical production data, assumptions regarding capital
expenditures and anticipated production declines. The reserves and average daily
production attributable to the BP transactions are based solely on our internal
estimates and have not been reviewed by our independent reserve engineers. There
is no assurance that the BP transactions will be completed or, if completed,
that our estimates of reserves and average daily production will prove correct.

     In order to preserve our strong financial position in a period of
cyclically high gas and oil prices, we hedged 40.8 MMbbls of oil at an average
price of $24.78 per Bbl and 70 Bcf of natural gas at an average price of $4.55
per MMbtu through 2004. We have agreed to sell all of the North Sea production
from those properties over the next two years to BP at a combination of fixed
and market sensitive prices pursuant to a contract entered into in connection
with the North Sea purchase agreement. The fixed price portion of our contract
with BP is included in the 40.8 MMbbl oil hedge.

     The BP transactions have received all necessary corporate approvals, and
are not conditioned upon financing, but are subject to customary closing
conditions, regulatory approvals under the U.S. Hart-Scott-Rodino Act and, in
the case of the North Sea properties, U.K. regulatory and other approvals.

     Completed Acquisitions.  A significant part of our growth strategy is to
increase oil and gas reserves, production and cash flow through an active
acquisition program. Apache has consummated several acquisitions since January
1, 2002.

     In December 2002, Apache completed the acquisition of certain South
Louisiana properties comprising 234,000 net acres (366 square miles) with
estimated net proved reserves of 30 MMboe, 88 percent of which is estimated to
be natural gas, for approximately $260 million, subject to normal post-closing
adjustments. The acquisition also includes 135 producing wells and access to 849
square miles of 3-D seismic data covering the relatively contiguous acreage
position. Based on our analysis of historical production rates, assumptions
regarding capital expenditures and anticipated production declines, we
anticipate 2003 net daily production to approximate 55 MMcf of natural gas and
2,100 barrels of oil. We also entered into a separate exploration joint venture
with the seller whereby the seller will actively generate prospects on certain
South Louisiana acreage for a total cost of $25 million over a two year period.

     We have also completed several smaller acquisitions since January 1, 2002,
for an aggregate of approximately $95 million. Together, these acquisitions
include proved reserves of approximately 20 MMboe.

     2002 Drilling Results.  During 2002, we completed 1,018 gross wells as
producers out of a total of 1,089 gross wells drilled. In the fourth quarter of
2002, we announced our fourth deep water discovery on our West Mediterranean
concession offshore Egypt, and a new discovery in our Ras El Hekma concession in
Egypt. These wells were, respectively, the 10th and 11th discoveries for us in
Egypt and our 15th and 16th discoveries worldwide for the year.

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

     Our executive offices are located at 2000 Post Oak Boulevard, Suite 100,
Houston, Texas 77056, and our telephone number is (713) 296-6000.

                                       S-3


                                  THE OFFERING

Common stock offered..........   6,200,000 shares

Common stock to be outstanding
after this offering...........   150,250,678 shares

Use of proceeds...............   We expect that our net proceeds from the
                                 offering will be approximately $337.5 million,
                                 assuming an offering price of $56.60 per share
                                 and after deducting underwriting discounts and
                                 commissions and estimated expenses of the
                                 offering payable by us. We intend to use the
                                 net proceeds from the offering, together with
                                 cash on hand, net cash generated from
                                 operations and short-term and long-term
                                 borrowings, to fund the cash requirements of
                                 the pending BP transactions. Pending such use,
                                 we will use the net proceeds to repay
                                 indebtedness under our commercial paper
                                 facilities and our money market lines of credit
                                 in the ordinary course of business or to make
                                 short-term investments. We will use any net
                                 proceeds not used to finance the BP
                                 transactions for general corporate purposes.

Dividends.....................   On December 18, 2002, we announced that our
                                 board of directors had declared a special 5
                                 percent dividend, payable in shares of our
                                 common stock, which will be paid on April 2,
                                 2003, to shareholders of record on March 12,
                                 2003. The board also declared the regular cash
                                 dividend on our common stock of $.10 per share.
                                 The cash dividend will be paid on February 21,
                                 2003, to shareholders of record on January 22,
                                 2003. Purchasers of our common stock in this
                                 offering who own their shares at the close of
                                 business on the applicable record date will be
                                 entitled to receive the common stock and cash
                                 dividends.

Risk factors..................   See "Risk Factors" and other information
                                 included in this prospectus supplement for a
                                 discussion of factors you should carefully
                                 consider before deciding to invest in shares of
                                 the common stock.

New York and Chicago Stock
Exchange symbol...............   APA

     The number of shares of our common stock to be outstanding after the
offering is based on 144,050,678 shares outstanding as of December 31, 2002, and
excludes:

      --   4,010,789 shares of treasury stock, of which 1,597,272 shares are
           reserved for issuance under one of our stock option plans (of which
           options to purchase 1,392,705 shares at an average exercise price of
           $52.43 per share are outstanding), 450,000 shares are reserved for
           certain restricted stock grants and 345,269 shares are reserved for
           issuance under our deferred delivery plan;

      --   4,305,652 shares of common stock reserved for issuance under our
           stock option plans, of which options to purchase 4,001,778 shares at
           an average exercise price of $37.02 per share are outstanding;

      --   3,927,065 shares reserved for issuance under our deferred delivery
           plan and for certain additional stock grants; and

      --   the shares issuable as a result of the 5 percent common stock
           dividend declared on December 18, 2002.

                                       S-4


                      SUMMARY HISTORICAL FINANCIAL AND OPERATING DATA

     We have provided in the tables below our selected financial and operating
data. The financial information for each of the years in the three-year period
ended December 31, 2001, and at December 31, 1999, 2000 and 2001, has been
derived from our audited financial statements. The financial information for the
nine-month periods ended September 30, 2001 and 2002, and at September 30, 2001
and 2002, has been derived from our unaudited financial statements. In our
management's opinion, these unaudited financial statements have been prepared on
the same basis as our audited financial statements except as noted below. You
should read the following financial information in conjunction with our
consolidated financial statements and related notes that we have incorporated by
reference in the accompanying prospectus.

<Table>
<Caption>
                                                                            NINE MONTHS ENDED
                                      YEAR ENDED DECEMBER 31,                 SEPTEMBER 30,
                              ---------------------------------------   -------------------------
                                1999(1)       2000(2)       2001(3)        2001          2002
                              -----------   -----------   -----------   -----------   -----------
                                                                               (UNAUDITED)
                                      (IN THOUSANDS, EXCEPT SHARE AND PER SHARE AMOUNTS)
                                                                       
INCOME STATEMENT DATA:
Total revenues(4)...........  $ 1,146,553   $ 2,283,904   $ 2,777,126   $ 2,272,113   $ 1,829,500
Net income..................      200,855       713,056       723,399       644,779       373,510
Income attributable to
  common stock..............      186,406       693,068       703,798       630,086       364,115
Net income per common share:
  Basic(5)..................         1.57          5.34          5.13          4.59          2.59
  Diluted(6)................         1.56          5.16          4.97          4.43          2.55
Cash dividends declared per
  common share(7)...........          .25           .19           .35           .25           .30
Net cash provided by
  operating activities......      638,174     1,529,386     1,934,727     1,527,964     1,009,269
BALANCE SHEET DATA (AT END
  OF PERIOD):
Working capital.............  $     6,290   $    76,673   $   175,291   $    88,214   $   369,208
Total assets................    5,502,543     7,481,950     8,933,656     9,066,735     9,248,709
Long-term debt..............    1,879,650     2,193,258     2,244,357     2,311,512     2,163,182
Shareholders' equity........    2,669,427     3,754,640     4,418,483     4,398,202     4,761,160
Common shares
  outstanding(8)............  125,396,110   135,998,223   137,103,179   137,090,273   143,966,713
</Table>

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

(1) Includes the results of the acquisitions of certain oil and gas properties
    from Petsec Energy Inc., Shell Offshore Inc. and affiliated Shell entities,
    British-Borneo Oil & Gas Plc and Shell Canada Limited after February 1,
    1999, May 18, 1999, June 18, 1999 and November 30, 1999, respectively.

(2) Includes the results of the acquisitions of certain oil and gas properties
    from Repsol, Collins & Ware, Occidental and Phillips after January 24, 2000,
    June 30, 2000, August 17, 2000, and December 29, 2000, respectively.

(3) Includes the results of the acquisitions of certain oil and gas properties
    from Repsol YPF and Fletcher Challenge Energy after March 22, 2001, and
    March 27, 2001, respectively.

(4) As a result of the consensus on Emerging Issues Task Force Issue 00-10,
    "Accounting for Shipping and Handling Fees and Costs," for the nine months
    ended September 30, 2002, third party gathering and transportation costs in
    the amount of $27.5 million have been reported as an operating expense
    instead of a reduction to revenues as previously reported. A
    reclassification has been made to reflect this change for the nine months
    ended September 30, 2001, resulting in an increase in reported revenue and
    operating expense for that period of $24.1 million. The change has no impact
    on income attributable to common stock. The income statement data for each
    of the years in the three-year period ended December 31, 2001, do not
    reflect the reclassification and report third party gathering and
    transportation costs as a reduction of revenues. For 1999, 2000 and 2001,
    the reclassification would result in an increase in reported revenue and
    operating expense of $15.1 million, $18.1 million and $32.3 million,
    respectively, with no impact on income attributable to common stock.

                                       S-5


(5) Does not take into account the 5 percent common stock dividend declared in
    December 2002. If the effects of the dividend had been taken into account,
    Net income per common share -- Basic would have been $1.50, $5.09 and $4.89
    for the years ended December 31, 1999, 2000 and 2001, respectively, and
    $4.37 and $2.47 for the nine month periods ended September 30, 2001 and
    2002, respectively.

(6) Does not take into account the 5 percent stock common dividend declared in
    December 2002. If the effects of the dividend had been taken into account,
    Net income per common share -- Diluted would have been $1.49, $4.91 and
    $4.73 for the years ended December 31, 1999, 2000 and 2001, respectively,
    and $4.22 and $2.43 for the nine month periods ended September 30, 2001 and
    2002, respectively.

(7) Does not take into account the 5 percent common stock dividend declared in
    December 2002. If the effects of the dividend had been taken into account,
    Cash dividends per common share would have been $.24, $.18 and $.33 for the
    years ended December 31, 1999, 2000 and 2001, respectively, and $.24 and
    $.29 for the nine month periods ended September 30, 2001 and 2002,
    respectively.

(8) Does not take into account the 5 percent common stock dividend declared in
    December 2002. If the effects of the dividend had been taken into account,
    common shares outstanding would have been 131,665,916 shares, 142,798,134
    shares and 143,958,338 shares for the years ended December 31, 1999, 2000
    and 2001, respectively, and 143,944,787 shares and 151,165,049 shares for
    the nine month periods ended September 30, 2001 and 2002, respectively.

<Table>
<Caption>
                                                                            NINE MONTHS ENDED
                                         YEAR ENDED DECEMBER 31,              SEPTEMBER 30,
                                    ----------------------------------   -----------------------
                                      1999        2000         2001         2001         2002
                                    --------   ----------   ----------   ----------   ----------
                                                                       
OPERATING DATA:
Proved reserves:
  Oil (Mbbls)(1)..................   415,242      522,473      599,388
  Natural gas (Bcf)...............     2,352        3,384        4,005
     Total proved reserves
       (Mboe)(2)..................   807,172    1,086,418    1,266,943
  Reserves outside North America
     (% of total).................        27%          20%          25%
  Reserve replacement ratio(3)....       360%         393%         244%
  Reserve life index (years)(4)...      10.8         11.4         10.1
  Finding and development costs
     per Boe(2)(5)................  $   5.79   $     5.65   $     5.64
Average daily production:
  Oil (Mbbls/day)(1)..............        95          122          156          152          162
  Natural gas (MMcf/day)..........       656          831        1,127        1,115        1,082
     Total production
       (Mboe/day)(2)..............       204          261          344          338          343
Average lease operating costs per
  Boe(2)..........................  $   2.56   $     2.68   $     3.24   $     3.20   $     3.67
</Table>

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

(1) Includes crude oil, condensate and natural gas liquids.

(2) 6 Mcf of natural gas = 1 Boe.

(3) Total reserve additions for the period, including revisions and net of
    property sales, divided by annual production.

(4) Total proved reserves at period end divided by annual production.

(5) Total capitalized costs incurred for the period, excluding capitalized
    interest and property sales, divided by total reserve additions for the
    period, including revisions.

                                       S-6


                                  RISK FACTORS

     Before making an investment in shares of our common stock, you should
carefully consider the risks described below, as well as the information
included or incorporated by reference in this prospectus supplement and the
accompanying prospectus. In addition, please read "Special Note Regarding
Forward-Looking Statements" in this prospectus supplement, where we describe
additional uncertainties associated with our business and the forward-looking
statements included or incorporated by reference in this prospectus supplement
and the accompanying prospectus.

REPERCUSSIONS FROM THE TERRORIST ACTS COMMITTED IN THE UNITED STATES COULD HARM
OUR BUSINESS OPERATIONS AND ADVERSELY IMPACT OUR ABILITY TO MEET OUR
EXPECTATIONS AND TO FULFILL OTHER FORWARD-LOOKING STATEMENTS CONTAINED IN THIS
PROSPECTUS SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS.

     The terrorist attacks on September 11, 2001, have caused instability in the
world's markets. There can be no assurance that the current armed hostilities
will not escalate or that these terrorist attacks, or the United States'
responses to them, will not lead to further acts of terrorism and civil
disturbances in the United States or elsewhere, which may further contribute to
the economic instability in the United States and the other regions in which we
operate. Armed conflict, civil unrest, additional terrorist activities and the
attendant political instability and societal disruption may reduce demand for
our products or disrupt our ability to conduct our exploration, production,
development and marketing activities, which could harm our business.

OIL AND NATURAL GAS PRICES ARE VOLATILE. VOLATILITY IN OIL AND NATURAL GAS
PRICES CAN ADVERSELY AFFECT OUR RESULTS AND THE PRICE OF OUR COMMON STOCK. THIS
VOLATILITY ALSO MAKES VALUATION OF OIL AND GAS PRODUCING PROPERTIES DIFFICULT
AND CAN DISRUPT MARKETS.

     Oil and natural gas prices have historically been, and are likely to
continue to be, volatile. The prices for oil and natural gas are subject to wide
fluctuation in response to relatively minor changes in the supply of and demand
for oil and natural gas, market uncertainty, worldwide economic conditions,
weather conditions, import prices, political conditions in major oil producing
regions, especially the Middle East, and actions taken by OPEC. The prices for
oil and natural gas could be significantly affected by the prospect and outcome
of war in Iraq, for example.

     Our quarterly results of operations may fluctuate significantly as a result
of variations in oil and natural gas prices and production performance. In
recent years, oil and natural gas price volatility has become increasingly
severe. You can expect the market price of our common stock to decline when our
quarterly results decline or at any time when events actually or potentially
adverse to us or the industry occur. Our common stock price may decline to a
price below the price you paid to purchase your shares of common stock in this
offering.

     This volatility makes it difficult to estimate with precision the value of
producing properties in acquisitions and to budget and project the return on
exploration and development projects involving our oil and gas properties. In
addition, unusually volatile prices often disrupt the market for oil and gas
properties, as buyers and sellers have more difficulty agreeing on the purchase
price of properties.

A SUBSTANTIAL OR EXTENDED DECLINE IN OIL AND GAS PRICES WOULD HAVE A MATERIAL
ADVERSE EFFECT ON US.

     A substantial or extended decline in oil and gas prices would have a
material adverse effect on our financial position, results of operations,
quantities of oil and gas that may be economically produced, and access to
capital. A significant decrease in price levels for an extended period would
negatively affect us in several ways:

      --   our cash flow would be reduced, decreasing funds available for
           capital expenditures employed to replace reserves or increase
           production;

      --   certain reserves would no longer be economic to produce, leading to
           both lower proved reserves and cash flow; and

                                       S-7


      --   access to other sources of capital, such as equity or long-term debt
           markets, could be severely limited or unavailable.

Consequently, our revenues and profitability would suffer.

OUR ABILITY TO SELL OUR OIL AND GAS PRODUCTION COULD BE MATERIALLY HARMED IF WE
FAIL TO OBTAIN ADEQUATE SERVICES SUCH AS TRANSPORTATION AND PROCESSING.

     The sale of our oil and gas production, particularly outside of North
America, depends on a number of factors beyond our control, including the
availability and capacity of transportation and processing facilities. Our
failure to obtain such services on acceptable terms could materially harm our
business.

WE HAVE RECORDED WRITE-DOWNS BECAUSE OF FULL COST ACCOUNTING RULES AND MAY BE
REQUIRED TO DO SO AGAIN IN THE FUTURE.

     Under the full cost accounting rules of the U.S. Securities and Exchange
Commission ("SEC"), we review the carrying value of our proved oil and gas
properties each quarter on a country-by-country basis. Under these rules,
capitalized costs of proved oil and gas properties--net of accumulated
depreciation, depletion and amortization, and deferred income taxes--may not
exceed the present value of estimated future net cash flows from proved oil and
gas reserves, discounted at 10 percent, plus the lower of cost or fair value of
unproved properties included in the costs being amortized, net of related tax
effects.

     These rules generally require pricing future oil and gas production at the
unescalated oil and gas prices in effect at the end of each fiscal quarter. They
also require a write-down if the "ceiling" is exceeded, even if prices declined
for only a short period of time.

     If oil and gas prices fall significantly, a write-down may occur.
Write-downs required by these rules do not impact cash flow from operating
activities.

THE OIL AND GAS RESERVES DATA WE REPORT ARE ONLY ESTIMATES AND MAY PROVE TO BE
INACCURATE.

     There are numerous uncertainties inherent in estimating quantities of oil
and natural gas reserves of any category and in projecting future rates of
production and timing of development expenditures, which underlie the reserve
estimates, including many factors beyond our control. Reserve data represent
only estimates. In addition, the estimates of future net cash flows from our
proved reserves and their present value are based upon various assumptions about
future production levels, prices and costs that may prove to be incorrect over
time. Any significant variance from the assumptions could result in the actual
quantity of our reserves and future net cash flows from them being materially
different from the estimates. In addition, our estimated reserves may be subject
to downward or upward revision based upon production history, results of future
exploration and development, prevailing oil and gas prices, operating and
development costs and other factors.

     At December 31, 2001, approximately 24 percent of our estimated proved
reserves were undeveloped. Recovery of undeveloped reserves generally requires
significant capital expenditures and successful drilling operations. The reserve
data assumes that we can and will make these expenditures and conduct these
operations successfully, which may not occur.

IF WE FAIL TO ACQUIRE OR FIND ADDITIONAL RESERVES, OUR RESERVES AND PRODUCTION
WILL DECLINE MATERIALLY FROM THEIR CURRENT LEVELS.

     The rate of production from oil and gas properties generally declines as
reserves are depleted. Except to the extent that we acquire additional
properties containing proved reserves, conduct successful exploration and
development activities, successfully apply new technologies or, through
engineering studies, identify additional behind-pipe zones or secondary recovery
reserves, our proved reserves will decline materially as reserves are produced.
Future oil and gas production is, therefore, highly dependent upon our level of
success in acquiring or finding additional reserves.

                                       S-8


WE INCUR SUBSTANTIAL COSTS TO COMPLY WITH GOVERNMENT REGULATIONS, ESPECIALLY
REGULATIONS RELATING TO ENVIRONMENTAL PROTECTION, AND COULD INCUR EVEN GREATER
COSTS IN THE FUTURE.

     Our exploration, production, development and marketing operations are
regulated extensively at the federal, state and local levels, as well as by
other countries in which we do business. We have made and will continue to make
large expenditures in our efforts to comply with the requirements of
environmental and other regulations. Further, the oil and gas regulatory
environment could change in ways that might substantially increase these costs.

     Hydrocarbon-producing states regulate conservation practices and the
protection of correlative rights. These regulations affect our operations and
limit the quantity of hydrocarbons we may produce and sell. In addition, at the
U.S. federal level, the Federal Energy Regulatory Commission regulates
interstate transportation of natural gas under the Natural Gas Act. Other
regulated matters include marketing, pricing, transportation and valuation of
royalty payments.

     As an owner or lessee and operator of oil and gas properties, we are
subject to various federal, state, local and foreign regulations relating to
discharge of materials into, and protection of, the environment. These
regulations may, among other things, impose liability on us for the cost of
pollution clean-up resulting from operations, subject us to liability for
pollution damages, and require suspension or cessation of operations in affected
areas. Changes in or additions to regulations regarding the protection of the
environment could hurt our business.

     One of the responsibilities of owning and operating oil and gas properties
is paying for the cost of abandonment. Upon closing of our acquisition of the
North Sea properties, we have agreed to assume BP's abandonment obligation for
those properties, the cost of which we took into consideration in determining
the purchase price. Effective January 1, 2003, exploration and production
companies are required to reflect abandonment costs as a liability on their
balance sheets.

     Our purchase of the North Sea properties does not relieve BP of its
liabilities if we do not satisfy our abandonment obligation. To ensure our
payment of those costs, we have agreed to deliver a letter of credit to BP if
the rating of our senior unsecured debt is lowered by both Moody's and Standard
& Poor's. Any such letter of credit would be in an amount equal to the net
present value of future abandonment costs of the North Sea properties as of the
date of any such ratings change. If we are obligated to provide a letter of
credit, it will expire if either rating agency restores its rating to the
present level.

OUR BUSINESS COULD BE HARMED BY COMPETITION WITH OTHER COMPANIES.

     The oil and gas industry is highly competitive, and our business could be
harmed by competition with other companies. Because oil and gas are fungible
commodities, our principal form of competition is price competition. We strive
to maintain the lowest finding and production costs possible to maximize
profits. In addition, as an independent oil and gas company, we frequently
compete for reserve acquisitions, exploration leases, licenses, concessions and
marketing agreements against companies with financial and other resources
substantially larger than we possess. Many of our competitors have established
strategic long-term positions and maintain strong governmental relationships in
countries in which we may seek new entry.

WE DO NOT INSURE AGAINST ALL POTENTIAL LOSSES AND COULD BE SERIOUSLY HARMED BY
UNEXPECTED LIABILITIES.

     Exploration for and production of oil and natural gas can be hazardous,
involving natural disasters and other unforeseen occurrences such as blowouts,
cratering, fires and loss of well control, which can damage or destroy wells or
production facilities, injure or kill people, and damage property and the
environment. We maintain insurance against many potential losses or liabilities
arising from our operations in accordance with customary industry practices and
in amounts that we believe to be prudent. However, our insurance does not
protect us against all operational risks.

                                       S-9


OUR HEDGING ACTIVITIES MAY PREVENT US FROM BENEFITING FROM PRICE INCREASES AND
MAY EXPOSE US TO OTHER RISKS.

     To the extent that we engage in hedging activities, we may be prevented
from realizing the benefits of price increases above the levels of the hedges.
In addition, we are subject to risks associated with differences in prices at
different locations, particularly where transportation constraints restrict our
ability to deliver oil and gas volumes to the delivery point to which the
hedging transaction is indexed.

THE PENDING BP TRANSACTIONS MIGHT NOT BE CONSUMMATED AS EXPECTED.

     The BP transactions have received all necessary corporate approvals and are
not conditioned upon financing, but are subject to customary closing conditions,
regulatory approvals under the U.S. Hart-Scott-Rodino Act and, in the case of
the North Sea properties, U.K. regulatory and other approvals. We expect to
satisfy those remaining conditions. Owners of other working interests in certain
of the Gulf of Mexico properties have preferential rights to purchase portions
of the interests we expect to acquire from BP that, if exercised, would reduce
the interests we purchase in those fields and the purchase price we would pay.

     While we expect that the BP transactions will be closed and funded, we
cannot be sure that the transactions will be completed.

WHEN WE ACQUIRE OIL AND GAS PROPERTIES, SUCH AS THOSE FROM BP, OUR FAILURE TO
FULLY IDENTIFY AND CORRECTLY EVALUATE POTENTIAL PROBLEMS, TO PROPERLY ESTIMATE
RESERVES OR PRODUCTION RATES OR COSTS, OR TO EFFECTIVELY INTEGRATE THE ACQUIRED
OPERATIONS COULD SERIOUSLY HARM US.

     We are actively engaged in acquiring oil and gas properties. When we
acquire properties, such as those from BP, our failure to fully identify
potential problems, to properly estimate reserves or production rates or costs,
or to effectively integrate the acquired operations could seriously harm us.

     Although we perform reviews of acquired properties and applicable records
and contracts that we believe are consistent with industry practices, we do not
review in depth every individual property involved in each acquisition.
Ordinarily we focus on higher-value properties and sample the remainder.
However, even a detailed review of properties and applicable records and
contracts may not necessarily reveal existing or potential problems, nor will it
permit us to become sufficiently familiar with the properties to assess fully
their deficiencies and potential. Inspections may not always be performed on
every well, and environmental problems, such as ground water contamination, are
not necessarily observable even when an inspection is undertaken. Our review may
not sufficiently identify or evaluate applicable contracts under which third
parties may assert preferential rights to purchase some of the properties that
we believe we have acquired, rights to change or contest the operatorship of
acquired properties, or rights with respect to acquired properties under
agreements providing for areas of mutual interest. Even when we identify such
third party rights, we may not correctly evaluate their applicability or
potential consequences because of uncertain legal standards and for other
reasons.

     Even when problems are identified, we often assume environmental and other
risks and liabilities in connection with acquired properties. There are numerous
uncertainties inherent in estimating quantities of proved oil and gas reserves
and actual future production rates and associated costs with respect to acquired
properties. Actual results may vary substantially from those assumed in the
estimates. In addition, acquisitions may have adverse effects on our operating
results, particularly during the periods in which the operations of acquired
businesses are being integrated into our ongoing operations.

OUR NON-U.S. OPERATIONS, ESPECIALLY IN DEVELOPING COUNTRIES, ARE SUBJECT TO
INCREASED RISKS AND UNCERTAINTIES.

     Our non-U.S. oil and natural gas exploration, development and production
activities are subject to:

      --   political and economic uncertainties, including, among others,
           changes, sometimes frequent or marked, in governmental energy
           policies or the personnel administering them;

      --   expropriation of property;

                                       S-10


      --   cancellation or modification of contract rights;

      --   foreign exchange restrictions;

      --   currency fluctuations;

      --   risks of loss due to civil strife, acts of war, guerrilla activities
           and insurrection;

      --   royalty and tax increases; and

      --   other risks arising out of foreign governmental sovereignty over the
           areas in which our operations are conducted.

These risks may be higher in the developing countries in which we conduct these
activities. Consequently, our non-U.S. exploration, development and production
activities may be substantially affected by factors beyond our control, any of
which could materially adversely affect our financial position or results of
operations. Furthermore, in the event of a dispute arising from our non-U.S.
operations, we may be subject to the exclusive jurisdiction of courts outside
the United States or may not be successful in subjecting non-U.S. persons to the
jurisdiction of the courts in the United States, which could adversely affect
the outcome of the dispute.

A DECLINE IN THE CONDITION OF THE CAPITAL MARKETS OR A SUBSTANTIAL RISE IN
INTEREST RATES COULD HARM US.

     If the condition of the capital markets utilized by us to finance our
operations materially declines, we might not be able to finance our operations
on terms we consider acceptable. In addition, a substantial rise in interest
rates would decrease our net cash flows.

ADVERSE CHANGES IN THE EXCHANGE RATES WITH SOME FOREIGN CURRENCIES COULD HARM
US.

     Our cash flow stream relating to certain international operations is based
on the U.S. dollar equivalent of cash flows measured in foreign currencies.
Australian gas production is sold under fixed-price Australian dollar contracts
and over half the costs incurred are paid in Australian dollars. Revenue and
disbursement transactions denominated in Australian dollars are converted to
U.S. dollar equivalents based on the exchange rate on the transaction date.
Reported cash flow relating to Canadian operations is based on cash flows
measured in Canadian dollars converted to the U.S. dollar equivalent based on
the average of the Canadian and U.S. dollar exchange rates for the period
reported. Substantially all of our international transactions, outside of Canada
and Australia, are denominated in U.S. dollars.

     A decrease in value of 10 percent in the Canadian dollar, the Australian
dollar and Polish zloty relative to the U.S. dollar from the September 30, 2002
exchange rates would result in a foreign currency loss of approximately $16.0
million, based on September 30, 2002 amounts.

     The U.S. and Canadian energy markets continue to evolve into a single
energy market. In light of this continuing transformation, we adopted the U.S.
dollar as our functional currency in Canada, effective October 1, 2002. The U.S.
dollar is now the functional currency for all our foreign operations.

SUBSTANTIAL SALES OF OUR COMMON STOCK COULD CAUSE OUR STOCK PRICE TO DECLINE.

     If our existing stockholders sell a large number of shares of our common
stock or the public market perceives that existing stockholders might sell
shares of common stock, the market price of our common stock could significantly
decline. All of the shares offered by this prospectus supplement and the
accompanying prospectus will be freely tradable without restriction or further
registration under the federal securities laws unless purchased by an
"affiliate," as that term is defined in Rule 144 under the Securities Act of
1933. The outstanding shares subject to lock-up agreements between certain of
our directors and executive officers and the underwriters may be sold 90 days
after the effective date of this offering, except as noted in "Underwriting."

                                       S-11


OUR STOCKHOLDER RIGHTS PLAN, CHARTER, BYLAWS, DELAWARE LAW AND OUR DEBT
SECURITIES DISCOURAGE UNSOLICITED TAKEOVER PROPOSALS AND COULD PREVENT YOU FROM
REALIZING A PREMIUM FOR YOUR COMMON STOCK.

     We have a stockholder rights plan that may have the effect of discouraging
unsolicited takeover proposals. The rights issued under the stockholder rights
plan would cause substantial dilution to a person or group that attempts to
acquire us on terms not approved in advance by our board of directors. In
addition, our charter, bylaws, Delaware law and our debt securities contain
provisions that may discourage unsolicited takeover proposals that stockholders
may consider to be in their best interests. The stockholder rights plan and
these provisions are described in "Description of Capital Stock--Stockholder
Rights Plan" beginning on page 11 of the accompanying prospectus, and in
"--Anti-Takeover Effect of Provisions of Apache's Charter and Bylaws and
Delaware Law" beginning on page 13 of the accompanying prospectus. Our
obligation to purchase our debt securities upon a change in control is described
in "Description of Debt Securities--We Are Obligated to Purchase Debt Securities
Upon a Change in Control" beginning on page 27 of the accompanying prospectus.

     Together these provisions and the stockholder rights plan may discourage
transactions that otherwise could involve payment of a premium over prevailing
market prices for your common stock.

INVESTORS IN OUR SECURITIES MAY ENCOUNTER DIFFICULTIES IN OBTAINING, OR MAY BE
UNABLE TO OBTAIN, RECOVERIES FROM ARTHUR ANDERSEN WITH RESPECT TO ITS AUDITS OF
OUR FINANCIAL STATEMENTS.

     On March 14, 2002, our previous independent public accountant, Arthur
Andersen LLP, was indicted on federal obstruction of justice charges arising
from the federal government's investigation of Enron Corp. On June 15, 2002, a
jury returned with a guilty verdict against Arthur Andersen following a trial.
As a public company, we are required to file with the SEC periodic financial
statements audited or reviewed by an independent public accountant. On March 29,
2002, we decided not to engage Arthur Andersen as our independent auditors, and
engaged Ernst & Young LLP to serve as our new independent auditors for 2002.
However, we are incorporating in this prospectus supplement and the accompanying
prospectus financial statements for 2001, 2000 and 1999 that were audited by
Arthur Andersen. Investors in our securities may encounter difficulties in
obtaining, or be unable to obtain, from Arthur Andersen with respect to its
audits of our financial statements relief that may be available to investors
under the federal securities laws against auditing firms.

               SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

     This prospectus supplement, the accompanying prospectus, and the documents
incorporated herein and therein by reference contain statements that constitute
"forward looking statements" within the meaning of Section 27A of the Securities
Act of 1933 and Section 21E of the Securities Exchange Act of 1934. All
statements other than statements of historical facts, including, without
limitation, those relating to our future financial position, business strategy,
budgets, reserve information, projected levels of production, projected costs
and plans and objectives of management for future operations, are
forward-looking statements.

     Words such as "expect," "anticipate," "estimate," "intend," "plan,"
"believe" and similar expressions are intended to identify forward-looking
statements.

     Although we believe our expectations reflected in forward-looking
statements are based on reasonable assumptions, no assurance can be given that
these expectations will prove to have been correct. Important factors that could
cause actual results to differ materially from the expectations reflected in the
forward-looking statements include, among others:

      --   the market prices of oil and gas;

      --   uncertainty of drilling results, reserve estimates and reserve
           replacement;

      --   operating uncertainties and hazards;

      --   economic and competitive conditions;

                                       S-12


      --   natural disasters and other changes in business conditions;

      --   inflation rates;

      --   legislative and regulatory changes;

      --   financial market conditions;

      --   accuracy, completeness and veracity of information received from BP;

      --   wars and acts of terrorism or sabotage;

      --   political and economic uncertainties of foreign governments; and

      --   future business decisions.

Additional factors are discussed under "Risk Factors" beginning on page S-7 of
this prospectus supplement.

     In light of these risks, uncertainties and assumptions, the events
anticipated by our forward-looking statements might not occur. We undertake no
obligation to update or revise our forward-looking statements, whether as a
result of new information, future events or otherwise.

                                USE OF PROCEEDS

     We estimate the net proceeds from the offering of common stock to be
approximately $337.5 million, or $388.2 million if the underwriters'
over-allotment option is exercised in full, assuming an offering price of $56.60
per share and after deducting underwriting discounts and commissions and
estimated expenses of the offering payable by us.

     We intend to use the net proceeds from the offering, together with cash on
hand, net cash generated from operations and short-term and long-term
borrowings, to fund the cash requirements of the pending BP transactions.
Pending such use, we will use the net proceeds of the offering to repay
indebtedness under our commercial paper facilities and our money market lines of
credit in the ordinary course of our business or to make short-term investments.
The amount of repayment of indebtedness will depend, in part, on the closing of
the BP transactions. We will use any net proceeds not used to finance the BP
transactions for general corporate purposes. As of December 31, 2002, we had
$271.4 million face amount of commercial paper discounted at an average weighted
rate of 1.35 percent per annum and $8.9 million principal amount outstanding
under our money market lines of credit bearing interest at a variable rate of
LIBOR plus 15 basis points.

                                       S-13


                                 CAPITALIZATION

     The following table sets forth, as of September 30, 2002, our cash and cash
equivalents and capitalization on:

      --   an actual basis; and

      --   an as adjusted basis giving effect to our receipt of the estimated
           net proceeds from the sale of the shares we are selling in the
           offering and the application of the net proceeds pending the closing
           of the BP transactions.

     The as adjusted cash and cash equivalents and capitalization amounts assume
that the over-allotment option is not exercised. The as adjusted amounts do not
reflect the effects of our acquisitions in the fourth quarter of 2002, which are
not material to our capitalization, or the financing of the pending BP
transactions. The as adjusted amounts are based on a common stock per share
price of $56.60, which was the last reported sale price of our common stock on
the New York Stock Exchange on January 10, 2003. The table should be read in
conjunction with our consolidated financial statements and related notes
incorporated by reference in this prospectus supplement and the accompanying
prospectus.

<Table>
<Caption>
                                                             AS OF SEPTEMBER 30, 2002
                                                             ------------------------
                                                               ACTUAL     AS ADJUSTED
                                                             ----------   -----------
                                                                   (UNAUDITED)
                                                                  (IN THOUSANDS)
                                                                    
Cash and Cash Equivalents..................................  $  167,471   $  220,167
                                                             ==========   ==========
Total Debt:
Apache:
  7.95% notes due 2026.....................................  $  178,609   $  178,609
  7.625% debentures due 2096...............................     149,175      149,175
  7.625% notes due 2019....................................     149,127      149,127
  7.375% debentures due 2047...............................     148,009      148,009
  7.7% notes due 2026......................................      99,659       99,659
  7.0% notes due 2018......................................     148,432      148,432
  6.25% notes due 2012.....................................     397,255      397,255
  Money market lines of credit and commercial paper........     284,800           --
Subsidiary and other obligations:
  Apache Finance Australia 6.5% notes due 2007.............     169,228      169,228
  Apache Finance Australia 7.0% notes due 2009.............      99,521       99,521
  Apache Finance Canada 7.75% notes due 2029...............     297,011      297,011
  Fletcher Notes...........................................       5,356        5,356
  Apache Clearwater, Inc. .................................      37,000       37,000
                                                             ----------   ----------
          Total debt.......................................   2,163,182    1,878,382
                                                             ----------   ----------
Preferred Interests of Subsidiaries........................     436,415      436,415
                                                             ----------   ----------
Shareholders' Equity:
  Series B preferred stock.................................      98,387       98,387
  Common stock.............................................     184,974      192,724
  Paid-in capital..........................................   3,038,248    3,367,994
  Retained earnings........................................   1,658,081    1,658,081
  Treasury stock...........................................    (110,616)    (110,616)
  Accumulated other comprehensive income...................    (107,914)    (107,914)
                                                             ----------   ----------
          Total shareholders' equity.......................   4,761,160    5,098,656
                                                             ----------   ----------
          Total capitalization.............................  $7,360,757   $7,413,453
                                                             ==========   ==========
</Table>

                                       S-14


                          PRICE RANGE OF COMMON STOCK

     Our common stock is listed for trading on the New York Stock Exchange and
the Chicago Stock Exchange under the symbol "APA." The following table sets
forth on a per share basis the high and low sales prices for our common stock
for the quarters indicated. Prices shown are from the New York Stock Exchange
Composite Transactions Reporting System.

<Table>
<Caption>
                                                                HIGH       LOW
                                                              --------   --------
                                                                   
2000:
  First Quarter.............................................  $46.8181   $29.2045
  Second Quarter............................................   55.9090    40.0000
  Third Quarter.............................................   61.5341    42.1591
  Fourth Quarter............................................   67.4432    46.8182
2001:
  First Quarter.............................................  $66.2500   $49.2727
  Second Quarter............................................   60.7272    43.6818
  Third Quarter.............................................   49.4454    34.7727
  Fourth Quarter............................................   50.1182    36.9000
2002:
  First Quarter.............................................  $  58.20   $  44.36
  Second Quarter............................................     60.09      52.57
  Third Quarter.............................................     59.99      45.07
  Fourth Quarter............................................     60.64      49.44
</Table>

     On January 10, 2003, the last reported sale price for our common stock on
the New York Stock Exchange was $56.60 per share. Stockholders should obtain
current market quotations before making any decision with respect to an
investment in our common stock.

     At December 31, 2002, there were 144,050,678 shares of our common stock
outstanding, held by approximately 9,000 shareholders of record.

     Prices shown and shares outstanding exclude the shares issuable as a result
of the 5 percent stock dividend declared on December 18, 2002.

                                DIVIDEND POLICY

     We have paid cash dividends on our common stock for 36 consecutive years
through December 31, 2002. We increased the annual stock dividend to $.40 per
share in 2002. On December 18, 2002, we declared a special 5 percent common
stock dividend to be paid on April 2, 2003, to stockholders of record on March
12, 2003. We also declared a cash dividend on our common stock of $.10 per share
to be paid on February 21, 2003, to stockholders of record on January 22, 2003.
Although we expect to continue the payment of dividends at that level, future
dividend payments will depend upon our level of earnings, financial requirements
and other relevant factors.

     In December 1995, we declared a dividend of one preferred stock purchase
right for each share of our common stock outstanding on January 31, 1996 or
issued after that date. These rights are more fully described on pages 11 and 12
of the accompanying prospectus.

                                       S-15


                     MATERIAL U.S. FEDERAL TAX CONSEQUENCES
                      TO NON-U.S. HOLDERS OF COMMON STOCK

     The following is a summary of material U.S. federal income and estate tax
consequences expected to result under current law from the purchase, ownership
and taxable disposition of common stock by non-U.S. holders of common stock. A
"non-U.S. holder" is any person or entity other than one who is for U.S. federal
income tax purposes:

      --   a citizen or resident of the United States;

      --   a corporation, partnership or other entity created or organized in or
           under the laws of the United States or any state thereof;

      --   an estate, the income of which is includable in gross income for U.S.
           federal income tax purposes regardless of its source; or

      --   a trust whose administration is subject to the primary supervision of
           a U.S. court and which has one or more U.S. persons who have the
           authority to control all substantial decisions of the trust.

     This summary does not address all of the U.S. federal income and estate tax
considerations that may be relevant to non-U.S. holders in light of their
particular circumstances, such as a valid election to be treated as a U.S.
person, or to non-U.S. holders that may be subject to special treatment under
U.S. federal income tax laws. This summary does not discuss any aspect of state,
local or foreign taxation. This summary is based on current provisions of the
Internal Revenue Code of 1986, as amended, Treasury regulations, judicial
opinions, published positions of the Internal Revenue Service and other
applicable authorities, all of which are subject to change, possibly with
retroactive effect. In this prospectus supplement, the Internal Revenue Code of
1986, as amended, is called the "Code." Prospective purchasers of common stock
are advised to consult their tax advisors regarding the U.S. federal, state and
local, and non-U.S. income and other tax consequences of acquiring, holding and
disposing of common stock.

DIVIDENDS

     Apache pays cash dividends on its common stock. Any dividends paid to a
non-U.S. holder on shares of common stock will be subject to withholding of U.S.
federal income tax at a rate of 30 percent, unless a lower rate is prescribed
under an applicable tax treaty. U.S. federal income tax withholding will not be
required, however, if the dividends are effectively connected with the conduct
of a trade or business of the non-U.S. holder within the United States or, in
the case of an applicable tax treaty, are attributable to a U.S. permanent
establishment maintained by the non-U.S. holder. Dividends that are effectively
connected with the conduct of a trade or business within the United States, or
are attributable to a U.S. permanent establishment will be subject to U.S.
federal income tax on a net income basis which is not collected by withholding
provided the non-U.S. holder files the appropriate certification with Apache or
its agent. Any dividends received by a foreign corporation that are effectively
connected with the conduct of a trade or business within the United States may
also be subject to a "branch profits tax" at a rate of 30 percent or such lower
rate as may be specified by an applicable tax treaty.

     For purposes of the withholding tax rules discussed above and for purposes
of determining the applicability of a tax treaty rate under current Treasury
Regulations, dividends paid to an address outside the United States will be
presumed to be paid to a resident of the country of address, unless the payor
has knowledge to the contrary. Under Treasury Regulations (referred to as "final
regulations") that are effective for payments made after December 31, 2000, a
non-U.S. holder of common stock who wishes to claim the benefit of a tax treaty
rate is required to satisfy applicable certification and other requirements. In
addition, under the final regulations, in the case of common stock held by a
foreign partnership:

      --   the certification requirement is generally applied to the partners of
           the partnership; and

      --   the partnership is required to provide certain information, including
           a U.S. taxpayer identification number.

                                       S-16


     A non-U.S. holder of common stock that is eligible for a reduced rate of
U.S. federal income tax withholding pursuant to a tax treaty may obtain a refund
of any excess amounts currently withheld by filing an appropriate claim for
refund with the Internal Revenue Service.

SALE OR DISPOSITION OF COMMON STOCK

     A non-U.S. holder generally will not be subject to U.S. federal income tax
in respect of any gain recognized on the sale or other taxable disposition of
common stock so long as:

      --   the gain is not effectively connected with the conduct of a trade or
           business of the non-U.S. holder within the United States and, under
           an applicable tax treaty, is not attributable to a U.S. permanent
           establishment maintained by the non-U.S. holder;

      --   in the case of a non-U.S. holder who is an individual and holds the
           common stock as a capital asset, either:

           --   such holder is not present in the United States for 183 or more
                days during the taxable year of the disposition; or

           --   such holder does not have a "tax home" in the United States for
                U.S. federal income tax purposes and such holder does not
                maintain an office or other fixed place of business in the
                United States to which such gain is attributable;

      --   such non-U.S. holder is not subject to tax pursuant to the provisions
           of U.S. federal income tax law applicable to certain U.S.
           expatriates; and

      --   the common stock continues to be "regularly traded on an established
           securities market" for U.S. federal income tax purposes and the
           non-U.S. holder has not held, directly or indirectly, at any time
           during the five-year period ending on the date of disposition (or, if
           shorter, the non-U.S. holder's holding period) more than five percent
           of the outstanding common stock.

INFORMATION REPORTING AND BACKUP WITHHOLDING

     Apache must report annually to the Internal Revenue Service and to each
non-U.S. holder the amount of dividends paid to, and the tax withheld with
respect to, each non-U.S. holder. These reporting requirements apply regardless
of whether withholding was reduced by an applicable tax treaty. Copies of these
information returns may also be made available under the provisions of a treaty
or information exchange agreement with the tax authorities in the country in
which the non-U.S. holder resides or is established. Under current law, U.S.
backup withholding tax, which is a withholding tax at the applicable statutory
rate on certain payments to persons who fail to furnish the information required
under U.S. information reporting requirements, generally will not apply to
dividends paid on common stock to a non-U.S. holder at an address outside the
United States unless the payor has knowledge that the payee is a U.S. person.
However, under the final regulations, dividends paid on common stock after
December 31, 2000, may be subject to backup withholding unless applicable
certification requirements are satisfied.

     Payment of the proceeds from a sale of common stock to or through a U.S.
office of a broker will be subject to information reporting and backup
withholding unless the owner certifies as to its status as a non-U.S. holder
under penalties of perjury or otherwise establishes an exemption. Payment of the
proceeds from a sale of common stock to or through a non-U.S. office of a broker
generally will not be subject to information reporting or backup withholding.
However, if such broker is a U.S. person, a "controlled foreign corporation" or
a foreign person that derives 50 percent or more of its gross income from the
conduct of a trade or business in the United States, such payment will be
subject to information reporting, but currently not backup withholding, unless
such broker has documentary evidence in its records that the owner is a non-U.S.
holder and certain other conditions are met or the owner otherwise establishes
an exemption.

     Any amounts withheld under the backup withholding rules will be credited
against the non-U.S. holder's federal income tax liability, if any, or refunded,
provided the required information is furnished to the Internal Revenue Service.
                                       S-17


ESTATE TAX

     The fair market value of common stock owned, or treated as owned, by an
individual at the time of his death will be includable in his gross estate for
U.S. federal estate tax purposes and thus may be subject to U.S. federal estate
tax, even though the individual at the time of death is neither a citizen of nor
domiciled in the United States, unless an applicable estate tax treaty provides
otherwise.

GROWTH AND JOBS PLAN PROPOSED BY PRESIDENT BUSH ON JANUARY 7, 2003

     President George W. Bush recently proposed a new tax plan that, if enacted,
would eliminate U.S. federal income tax on certain dividends paid on common
stock by corporations that pay U.S. federal income tax. Under the proposal,
dividends would not be subject to U.S. federal income tax if (i) they are paid
from profits earned by corporations in 2002 or later, and (ii) the corporation
has paid U.S. federal income tax on such profits. As currently proposed,
President Bush's plan, if enacted, would require us, upon payment of dividends,
to inform shareholders of the amount of the dividend that would be "tax-free"
under the plan. The current proposal does not include sufficient detail to
permit us to determine what effect, if any, the proposal would have on the
withholding requirements applicable to non-U.S. persons who own shares of our
common stock. The proposal is preliminary in nature and must be reduced to
legislation that will be proposed in Congress. There can be no assurance that
the proposal will be enacted into law.

                                       S-18


                                  UNDERWRITING

     Under the terms and subject to the conditions contained in an underwriting
agreement dated the date of this prospectus supplement, the underwriters named
below, for whom Morgan Stanley & Co. Incorporated is acting as the
representative, have severally agreed to purchase, and we have agreed to sell to
them, severally, the number of shares of our common stock indicated below:

<Table>
<Caption>
NAME                                                           NUMBER OF SHARES
- ----                                                           ----------------
                                                            
Morgan Stanley & Co. Incorporated...........................
Salomon Smith Barney Inc. ..................................
RBC Dain Rauscher Inc. .....................................
Robert W. Baird & Co. Incorporated..........................
A.G. Edwards & Sons, Inc. ..................................
Petrie Parkman & Co., Inc...................................
Raymond James & Associates, Inc. ...........................
                                                                  ----------
Total.......................................................       6,200,000
                                                                  ==========
</Table>

     The underwriters are offering the shares of common stock subject to their
acceptance of the shares from us and subject to prior sale. The underwriting
agreement provides that the obligations of the several underwriters to pay for
and accept delivery of the shares of common stock offered by this prospectus
supplement are subject to the approval of certain legal matters by their counsel
and to certain other conditions. The underwriters are obligated to take and pay
for all of the shares of common stock offered by this prospectus supplement if
any such shares are purchased. However, the underwriters are not required to
take or pay for the shares covered by the underwriters' over-allotment option
described below.

     The underwriters initially propose to offer part of the shares of common
stock directly to the public at the public offering price listed on the cover
page of this prospectus supplement and part to certain dealers at a price that
represents a concession not in excess of $      a share under the public
offering price. After the initial offering of the shares of our common stock,
the offering price and other selling terms may from time to time be varied by
the representatives.

     The following table shows public offering price, underwriting discount and
proceeds before expenses to Apache. This information assumes either no exercise
or full exercise by the underwriters of their over-allotment option.

<Table>
<Caption>
                                                                   TOTAL
                                                        ----------------------------
                                            PER SHARE   WITHOUT OPTION   WITH OPTION
                                            ---------   --------------   -----------
                                                                
Public offering price.....................     $              $              $
Underwriting discounts and commissions....     $              $              $
Proceeds, before expenses, to Apache......     $              $              $
</Table>

     The expenses of this offering, not including the underwriting discount and
commissions, are estimated at $265,000 and are payable by Apache.

     We have granted to the underwriters an option, exercisable for 30 days from
the date of this prospectus supplement, to purchase up to an aggregate of
930,000 additional shares of common stock at the public offering price listed on
the cover page of this prospectus supplement, less underwriting discounts and
commissions. The underwriters may exercise this option solely for the purpose of
covering over-allotments, if any, made in connection with the offering of the
shares of common stock hereby. To the extent the option is exercised, each
underwriter will become obligated, subject to certain conditions, to purchase
approximately the same percentage of the additional shares of common stock as
the number listed next to the underwriter's name in the next preceding table
bears to the total number of shares of common stock listed next to the name of
all underwriters in the next preceding table.

                                       S-19


     We and our directors and executive officers have agreed that, without the
prior written consent of Morgan Stanley & Co. Incorporated on behalf of the
underwriters, we, he or she will not, during the period ending 90 days after the
date of this prospectus supplement:

      --   offer, pledge, sell, contract to sell, sell any option or contract to
           purchase, purchase any option or contract to sell, grant any option,
           right or warrant to purchase, lend or otherwise transfer or dispose
           of, directly or indirectly, any shares of our common stock or any
           securities convertible into or exercisable or exchangeable for our
           common stock or file any registration statement under the Securities
           Act of 1933 with respect to the foregoing; or

      --   enter into any swap or other arrangement that transfers to another,
           in whole or in part, any of the economic consequences of ownership of
           the common stock;

whether any transaction described above is to be settled by delivery of common
stock or such other securities, in cash or otherwise. In addition, our directors
and executive officers have agreed that, without the prior consent of Morgan
Stanley & Co. Incorporated on behalf of the underwriters, they will not, during
the period ending 90 days after the date of this prospectus supplement, make any
demand for, or exercise any right with respect to, the registration of any
shares of our common stock or any securities convertible into or exercisable or
exchangeable for our common stock.

     The restrictions described in the preceding paragraph do not apply to:

      --   the sale of shares to the underwriters pursuant to the underwriting
           agreement;

      --   transactions by any person other than us relating to shares of our
           common stock or other securities acquired in open market transactions
           after the completion of this offering;

      --   any shares of common stock issued pursuant to our existing dividend
           reinvestment program;

      --   the grant of options or common stock under our stock and incentive
           plans as in effect at the date hereof or the issuance of shares of
           our common stock under our non-employee director stock plan or
           dividend reinvestment plan;

      --   the issuance by us of shares of our common stock upon the exercise of
           an option or a warrant or the conversion of a security outstanding on
           the date hereof and disclosed in this prospectus supplement and the
           accompanying prospectus; or

      --   the issuance by us of shares of our common stock in connection with a
           purchase of assets or other transaction described in this prospectus
           supplement and the accompanying prospectus.

     In addition, the restrictions on our directors and executive officers do
not apply to the sale of shares of common stock upon the exercise of options for
less than 9,000 shares of common stock held by one of our executive officers
under our stock and incentive plans, which options will expire within 90 days of
the date of this prospectus supplement, or any transfer or disposition of common
stock to Apache pursuant to a cashless exercise of an option to purchase common
stock granted pursuant to a benefit plan and existing as of the date of this
prospectus supplement.

     In order to facilitate the offering of the common stock, the underwriters
may engage in transactions that stabilize, maintain or otherwise affect the
price of the common stock. Specifically, the underwriters may sell more shares
than they are obligated to purchase under the underwriting agreement, creating a
short position. A short sale is covered if the short position is no greater than
the number of shares available for purchase by the underwriters under the
over-allotment option. The underwriters can close out a covered short sale by
exercising the over-allotment option or purchasing shares in the open market. In
determining the source of shares to close out a covered short sale, the
underwriters will consider, among other things, the open market price of shares
compared to the price available under the over-allotment option. The
underwriters may also sell shares in excess of the over-allotment option,
creating a naked short position. The underwriters must close out any naked short
position by purchasing shares in the open market. A naked short position is more
likely to be created if the underwriters are concerned that there may be
downward pressure on the price of the common stock in the open market after
pricing that could adversely affect investors who purchase in the offering. As
an
                                       S-20


additional means of facilitating the offering, the underwriters may bid for, and
purchase, shares of common stock in the open market to stabilize the price of
the common stock. The underwriting syndicate may also reclaim selling
concessions allowed to an underwriter or a dealer for distributing the common
stock in the offering, if the syndicate repurchases previously distributed
common stock to cover syndicate short positions or to stabilize the price of the
common stock. These activities may raise or maintain the market price of the
common stock above independent market levels or prevent or retard a decline in
the market price of the common stock. The underwriters are not required to
engage in these activities and may end any of these activities at any time.

     In the ordinary course of their business, certain of the underwriters and
their respective affiliates have provided, or may in the future provide,
investment banking and other financial services to us or our subsidiaries,
including underwriting, the provision of financial advice and the extension of
credit. These underwriters and their affiliates have received, and may in the
future receive, customary fees and commissions for their services. Morgan
Stanley has performed investment banking and other financial services for Apache
and has received compensation for these services, which included services to
Apache in connection with the BP transactions. Salomon Smith Barney Inc. acted
as co-arranger on the $1.5 billion global credit facility that we entered into
on June 3, 2002.

     We have agreed to indemnify the underwriters against a variety of
liabilities, including liabilities under the Securities Act of 1933.

                                 LEGAL MATTERS

     Chamberlain, Hrdlicka, White, Williams & Martin, Houston, Texas, our
outside legal counsel, and our Vice President and Associate General Counsel,
Eric L. Harry, or our Attorney and Assistant Secretary, Jeffrey B. King, will
issue opinions about some legal matters in connection with the offering. As of
December 31, 2002, Mr. Harry owned 5,060 shares of common stock through Apache's
401(k) savings plan, held 3,300 restricted shares of common stock (none of which
was vested), held employee stock options to purchase 11,826 shares of common
stock (of which options to purchase 9,020 shares were currently exercisable) and
held conditional grants covering 9,382 shares of common stock (none of which was
vested). As of December 31, 2002, Mr. King owned 102 shares of common stock
through Apache's 401(k) savings plan, held employee stock options to purchase
10,108 shares of common stock (of which options to purchase 4,082 shares were
currently exercisable) and held conditional grants covering 6,379 shares of
common stock (none of which was vested). Sidley Austin Brown & Wood LLP, New
York, New York, will issue an opinion about some legal matters in connection
with the offering for the underwriters.

                                    EXPERTS

     The audited consolidated financial statements of Apache Corporation
incorporated by reference in this prospectus supplement and the accompanying
prospectus have been audited by Arthur Andersen LLP, independent public
accountants, as indicated in their report with respect thereto, and are included
herein in reliance upon the authority of said firm as experts accounting and
auditing in giving said report.

     On March 29, 2002, we decided not to engage Arthur Andersen as our
independent auditors, and engaged new independent auditors for 2002. See "Risk
Factors--Investors in our securities may encounter difficulties in obtaining, or
may be unable to obtain, recoveries from Arthur Andersen with respect to its
audits of our financial statements."

                                       S-21


             WHERE YOU CAN FIND MORE INFORMATION ABOUT THE COMPANY

     We file annual, quarterly and current reports, proxy statements and other
information with the SEC under the Securities Exchange Act of 1934. You may read
and copy any document we file at the SEC public reference room located at 450
Fifth Street, N.W., Judiciary Plaza, Room 1024, Washington, D.C. 20549. You may
obtain information on the operation of the public reference room in Washington,
D.C. by calling the SEC at 1-800-SEC-0330.

     You may also inspect and copy our SEC filings, the complete registration
statement and other information at the offices of the New York Stock Exchange
located at 20 Broad Street, 16th Floor, New York, New York 10005.

     We file information electronically with the SEC. Our SEC filings also are
available from the SEC's Internet site at http://www.sec.gov, which contains
reports, proxy and information statements, and other information regarding
issuers that file electronically.

                                       S-22


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