<PAGE>   1
 
     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JULY 15, 1999
 
                                                 REGISTRATION NO. 333-
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ---------------------
                                    FORM S-3
            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
                             ---------------------
                             NOBLE AFFILIATES, INC.
             (Exact name of Registrant as specified in its charter)
 

<TABLE>
<S>                                                 <C>
                     DELAWARE                                           73-0785597
          (State or other jurisdiction of                            (I.R.S. Employer
          incorporation or organization)                            Identification No.)
</TABLE>

 
                               110 WEST BROADWAY
                            ARDMORE, OKLAHOMA 73401
                                 (405) 223-4110
  (Address, including zip code, and telephone number, including area code, of
                   Registrant's principal executive offices)
                             ---------------------
                                 ROBERT KELLEY
          CHAIRMAN OF THE BOARD, PRESIDENT AND CHIEF EXECUTIVE OFFICER
                             NOBLE AFFILIATES, INC.
                               110 WEST BROADWAY
                            ARDMORE, OKLAHOMA 73401
                                 (405) 223-4110
 (Name, address, including zip code, and telephone number, including area code,
                             of agent for service)
                             ---------------------
                                   Copies to:
 
                                  KENN W. WEBB
                            THOMPSON & KNIGHT, P.C.
                        1700 PACIFIC AVENUE, SUITE 3300
                               THOMPSON & KNIGHT
                              DALLAS, TEXAS 75201
                                 (214) 969-1700
                             ---------------------
    APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: As soon as
practicable after the effective date of this Registration Statement.
 
    If the only securities being registered on this Form are being offered
pursuant to dividend or interest reinvestment plans, please check the following
box.  [ ]
 
    If any of the securities being registered on this Form are to be offered on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box.  [X]
 
    If this Form is filed to register additional securities for an Offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same Offering.  [ ]
 
    If this Form is a post-effective amendment filed pursuant to Rule 462(c)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same Offering.  [ ]
 
    If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box.  [ ]
                             ---------------------
 
                        CALCULATION OF REGISTRATION FEE
 

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
                   TITLE OF EACH CLASS OF                        PROPOSED MAXIMUM           AMOUNT OF
                SECURITIES TO BE REGISTERED                  AGGREGATE OFFERING PRICE  REGISTRATION FEE(1)
------------------------------------------------------------------------------------------------------------
<S>                                                          <C>                      <C>
Debt Securities, Preferred Stock, Common Stock and
  Warrants..................................................       $800,000,000              $222,400
------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------
</TABLE>

 
(1) Pursuant to Rule 429 under the Securities Act of 1933, the Prospectus herein
    also relates to $225,000,000 of debt securities of Noble Affiliates, Inc.
    registered under Registration Statement No. 333-18929. A filing fee of
    $174,243 in respect of such securities was paid on December 27, 1996, upon
    the filing of such Registration Statement.
                             ---------------------
    THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF
THE SECURITIES ACT OF 1933 OR UNTIL THIS REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a),
MAY DETERMINE.
 
    Pursuant to Rule 429 under the Securities Act of 1933, the prospectus
included in this Registration Statement will also be used in connection with
Registration Statement No. 333-18929 previously filed by Noble Affiliates, Inc.
on Form S-3.
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

<PAGE>   2
 
                                   PROSPECTUS
 

<TABLE>
<S>                             <C>                             <C>
[LOGO]                                  $1,025,000,000                   Subject To Completion,
                                    Noble Affiliates, Inc.                  Dated July 15, 1999
</TABLE>

 
                       Debt Securities, Preferred Stock,
                             Common Stock, Warrants
 
                           -------------------------
 
     The information in this prospectus is not complete and may be changed. We
may not sell these securities until the registration statement filed with the
Securities and Exchange Commission is effective. This prospectus is not an offer
to sell theses securities and is not soliciting an offer to buy these securities
in any state where the offer and sale is not permitted.
 
     By this prospectus, we may offer up to $1,025,000,000 of debt securities,
preferred stock, common stock and warrants on terms to be determined at the time
of sale. We will provide more specific information regarding these securities in
supplements to this prospectus. You should read this prospectus, particularly
the Risk Factors beginning on page 4, and any supplement carefully before
investing.
 
                           -------------------------
 
     These securities have not been approved by the Securities and Exchange
Commission or by any State securities commission, nor have those organizations
determined if this prospectus is truthful or complete. Any representation to the
contrary is a criminal offense.
 
                           -------------------------
 
           The Date of this Prospectus is                     , 1999

<PAGE>   3
 
                               TABLE OF CONTENTS
 

<TABLE>
<S>                                                           <C>
About This Prospectus.......................................    3
Where You Can Find Information..............................    3
Risk Factors................................................    4
The Company.................................................    5
Use Of Proceeds.............................................    5
Ratio Of Earnings To Fixed Charges And Ratio Of Earnings To
  Combined Fixed Charges And Preferred Stock Dividend
  Requirements..............................................    5
Description Of Debt Securities..............................    5
Description Of Preferred Stock..............................   19
Description Of Common Stock.................................   22
Description Of Warrants.....................................   23
Plan of Distribution........................................   23
Legal Matters...............................................   23
Experts.....................................................   24
</TABLE>

 
                                        2

<PAGE>   4
 
                             ABOUT THIS PROSPECTUS
 
     This prospectus is part of a registration statement that we filed with the
Securities and Exchange Commission utilizing a shelf registration process. Under
this shelf process, we may sell the unsecured debt securities, preferred stock,
common stock and warrants described in this prospectus in one or more offerings
up to a total dollar amount of $1,025,000,000. This prospectus provides you with
a general description of the securities we may offer. Each time we offer to sell
securities, we will provide a prospectus supplement that will contain specific
information about the terms of that offering. The prospectus supplement may also
add, update or change information contained in this prospectus. You should read
both this prospectus and any prospectus supplement together with additional
information described below under "Where You Can Find Information".
 
                         WHERE YOU CAN FIND INFORMATION
 
     We file annual, quarterly and special reports, proxy statements and other
information with the SEC. You may read and copy any materials on file with the
SEC at the SEC's Public Reference Room at 450 Fifth Street, N.W., Judiciary
Plaza, Washington, D.C. 20549. Our filings are available to the public over the
Internet at the SEC's web site at http://www.sec.gov. Please call the SEC at
1-800-SEC-0330 for further information on the Public Reference Room.
 
     The SEC allows us to "incorporate by reference" the information we file
with it, which means that we can disclose important information to you by
referring you to those documents. The information incorporated by reference is
an important part of this prospectus, and information that we file later with
the SEC will automatically update and supersede this information. We incorporate
by reference the documents listed below and any future filings we make with the
SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of
1934 until we sell all of the securities:
 
     Our Quarterly Report on Form 10-Q for the quarter ended March 31, 1999.
 
     Our Annual Report on Form 10-K for the year ended December 31, 1998, as
amended.
 
     The description of our common stock and preferred stock purchase rights
contained in our registration statements filed under Section 12 of the
Securities Exchange Act of 1934.
 
     You can get a free copy of any of the documents incorporated by reference
by making an oral or written request directed to:
 
        Noble Affiliates, Inc.
          P.O. Box 1967
          Ardmore, Oklahoma 73402
          Attn: Vice President -- Finance and Treasurer
          Telephone (405) 223-4110
 
     You should rely only on the information contained or incorporated in this
prospectus or any prospectus supplement. We have not authorized anyone else to
provide you with different information. You should not rely on any other
representations. Our affairs may change after this prospectus or any supplement
is distributed. You should not assume that the information in this prospectus or
any supplement is accurate as of any date other than the date on the front of
those documents. You should read all information supplementing this prospectus.
 
                                        3

<PAGE>   5
 
                                  RISK FACTORS
 
     You should carefully consider the information contained in this prospectus
and the following factors, among others, before purchasing the offered
securities.
 
VOLATILE PRODUCT PRICES AND MARKETS COULD ADVERSELY AFFECT OUR PERFORMANCE AND
FINANCIAL CONDITION.
 
     The results of our operations are highly dependent upon the prices of and
demand for oil and gas. Historically, the markets for oil and gas have been
volatile and are likely to continue to be volatile in the future. Accordingly,
the prices received for our oil and gas production are dependent upon numerous
factors that will be beyond our control. These factors include, but are not
limited to, the level of ultimate consumer product demand, governmental
regulations and taxes, the price and availability of alternative fuels, the
level of imports and exports of oil and gas, and the overall economic
environment. Any significant decline in prices for oil and gas could have a
material adverse effect on our financial condition, results of operations and
quantities of reserves recoverable on an economic basis. If the industry
experiences significant price declines or other adverse market conditions, we
may not be able to generate sufficient cash flow from operations to meet our
obligations and make planned capital expenditures. In order to manage our
exposure to price risks in the sale of oil and gas, we may from time to time
enter into commodities futures or option contracts to hedge a portion of our
crude oil and natural gas sales volume, although we do not currently do so. Any
such hedging activities may prevent us from realizing the benefits of price
increases above the levels reflected in the hedges.
 
FAILURE TO FUND CONTINUED CAPITAL EXPENDITURES COULD ADVERSELY AFFECT OUR
PROPERTIES.
 
     If our revenues substantially decrease as a result of lower oil and gas
prices or otherwise, we may have limited ability to spend the capital necessary
to replace our reserves or to maintain production at current levels, resulting
in a decrease in production over time.
 
     We expect to continue to make capital expenditures for the acquisition,
exploration and development of oil and gas reserves. Historically, we financed
these expenditures primarily with cash flow from operations and proceeds from
debt and equity financings. We believe that, after considering the amount of our
debt, we will have sufficient cash flow from operations and available drawings
under our credit facilities and other debt financings to fund capital
expenditures. However, if our cash flow from operations is not sufficient to
satisfy our capital expenditure requirements, we cannot assure you that we will
be able to obtain additional debt or equity financing or other sources of
capital to meet these requirements. If we are not able to fund our capital
expenditures, then our interests in some properties might be reduced or
forfeited.
 
WE MAY BE UNABLE TO MAKE ATTRACTIVE ACQUISITIONS OR INTEGRATE ACQUIRED
COMPANIES, AND ANY INABILITY TO DO SO MAY DISRUPT OUR BUSINESS.
 
     One aspect of our business strategy calls for acquisitions of businesses
that complement or expand our current business. We cannot assure you that we
will be able to identify attractive acquisition opportunities. Even if we do
identify attractive candidates, we cannot assure you that we will be able to
complete the acquisition of them or do so on commercially acceptable terms. If
we acquire another business, we could have difficulty integrating its
operations, systems, management and other personnel and technology with our own.
These difficulties could disrupt our ongoing business, distract our management
and employees, increase our expenses and adversely affect our results of
operations. Even if these difficulties could be overcome, we cannot assure you
that the anticipated benefits of any acquisition would be realized. In addition,
we may incur debt or issue equity securities to pay for any future acquisitions.
The issuance of equity securities could be dilutive to our existing
stockholders.
 
                                        4

<PAGE>   6
 
                                  THE COMPANY
 
     Noble Affiliates, Inc. is a Delaware corporation organized in 1969 and is
principally engaged, through its subsidiaries, in the exploration, production
and marketing of oil and gas.
 
                                USE OF PROCEEDS
 
     We will use the proceeds we receive from selling the offered securities to
pay off outstanding debt or for other general corporate purposes. General
corporate purposes may include capital expenditures, acquisitions or any other
purposes that may be stated in the supplements to this prospectus. The proceeds
may be invested temporarily until they are used for their stated purpose.
 
          RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO
        COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDEND REQUIREMENTS
 
     The ratio of earnings to fixed charges for each of the periods indicated is
as follows:
 

<TABLE>
<CAPTION>
YEARS ENDED DECEMBER 31,
--------------------------------   THREE MONTHS ENDED
1994   1995   1996   1997   1998     MARCH 31, 1999
----   ----   ----   ----   ----   ------------------
<S>    <C>    <C>    <C>    <C>    <C>
(1)    1.22   4.48   3.85    (1)           (1)
</TABLE>

 
---------------
 
(1) The ratio is less than one because earnings were inadequate to cover the
    fixed charges for the period. Earnings were insufficient to cover fixed
    charges by approximately $1,958,000 in 1994, by approximately $253,461,000
    in 1998 and by approximately $13,158,000 for the three months ended March
    31, 1999.
 
     As of July 15, 1999 we had no outstanding preferred stock. Therefore,
unless otherwise stated in a prospectus supplement, the ratio of earnings to
fixed charges and the ratio of earnings to combined fixed charges and preferred
stock dividend requirements will be the same.
 
     For purposes of computing the ratios, the earnings calculation is: income
before taxes + fixed charges - capitalized interest. The fixed charges
calculation is: net interest expense + capitalized interest + interest portion
of rental expense.
 
                         DESCRIPTION OF DEBT SECURITIES
 
     We may issue debt securities from time to time in one or more series. The
prospectus supplement relating to each series of debt securities will describe
the particular terms of the series and the extent, if any, to which the general
provisions below may apply to the debt securities being offered.
 
     The debt securities will constitute indebtedness designated as either
senior debt securities or subordinated debt securities. We will issue senior
debt securities, if at all, under the indenture dated as of April 1, 1997
between Noble Affiliates, Inc. and U.S. Trust Company of Texas, N.A. (the
"senior trustee"), as supplemented by the first indenture supplement dated as of
April 2, 1997, as further supplemented by the second indenture supplement dated
as of August 1, 1997. We will issue subordinated debt securities, if at all,
under an indenture to be entered into between us and a trustee prior to the
issuance of such subordinated debt securities. A prospectus supplement will
include any new information regarding the trustee under either indenture.
 
     Currently, there are outstanding under the senior indenture $100,000,000 of
7.25% senior debentures due 2097 and $250,000,000 of 8% senior notes due 2027.
 
     The following discussion includes a summary description of all material
terms of the indentures, other than terms specifically relating to a particular
series of debt securities to be described in the prospectus supplement relating
to such series. This summary is not complete and we refer you to the full
indentures, including definitions of terms that are capitalized in this
prospectus. Unless we indicate otherwise,
 
                                        5

<PAGE>   7
 
references in this Description of Debt Securities section to Noble Affiliates
and "we", "us", and "our" and similar expressions refer to Noble Affiliates,
Inc. and not our subsidiaries. In certain cases below we have indicated that you
should read the indenture for more details about a particular section summarized
in this prospectus.
 
     Other than as described in "Provisions Applicable to the Senior
Indenture -- Certain Covenants of the Company," and only to the extent
applicable to the senior debt securities of a particular series, as indicated by
the applicable prospectus supplement, the indentures do not contain any
provisions affording you protection if we engage in a highly leveraged or other
risky transaction or if we experience a material adverse change in our financial
condition or results of operations.
 
GENERAL PROVISIONS APPLICABLE TO BOTH INDENTURES
 
     The indentures do not limit the aggregate amount of debt securities we may
issue, and we may issue debt securities from time to time in separate series up
to the aggregate amount authorized for the series. We may issue debt securities
in registered form without coupons, in bearer form with or without coupons
attached or in a form of one or more global securities in registered or bearer
form. We will offer bearer debt securities, if at all, only to non-United States
persons and to offices located outside of the United States of certain United
States financial institutions.
 
     The debt securities will be unsecured obligations. The senior debt
securities will be unsubordinated obligations and will rank equally with all of
our other unsecured and unsubordinated indebtedness. The subordinated debt
securities will be subordinated in right of payment to the prior payment in full
of our Senior Indebtedness (as defined below under "-- Certain Definitions"), as
described below under "Provisions Applicable to the Subordinated
Indenture -- Subordination" and in a prospectus supplement applicable to an
offering of subordinated debt securities.
 
     Since Noble Affiliates is a holding company, our rights and the rights of
our creditors, including you, to participate in a distribution of the assets of
our subsidiaries upon any liquidation or reorganization of any subsidiary, or
otherwise, will be subject to the prior claims of creditors of the subsidiary.
Our ability to pay principal of and interest on the debt securities depends, to
a large extent, upon the payment to us of dividends, interest or other charges
by our subsidiaries.
 
     The applicable prospectus supplement will describe the following terms of
the series of debt securities in respect of which we are delivering this
prospectus:
 
         (1) the title of the debt securities;
 
         (2) any limit on the aggregate principal amount of the debt securities;
 
         (3) whether the debt securities will be issued as registered debt
             securities, bearer debt securities or both, and any limitation on
             issuance of bearer debt securities and any provisions regarding the
             transfer or exchange of bearer debt securities, including exchange
             for registered debt securities of the same series;
 
         (4) whether any of the debt securities are to be issuable as global
             securities, whether the global securities are to be issued in
             temporary global form or permanent global form, and, if so, the
             terms and conditions, if any, upon which interests in the global
             securities may be exchanged, in whole or in part, for the
             individual debt securities that they represent;
 
         (5) the person to whom any interest on any debt security of the series
             will be payable if other than the person in whose name the debt
             security is registered on the regular record date;
 
         (6) the date or dates on which the debt securities will mature;
 
         (7) the rate or rates of interest, if any, or the method of interest
             calculation, that the debt securities will bear;
 
                                        6

<PAGE>   8
 
         (8) the date or dates from which any interest will accrue, the interest
             payment dates on which any interest on the debt securities will be
             payable and the regular record dates for any interest payable on
             any interest payment date;
 
         (9) the place or places where the principal of, premium, if any, and
             interest on the debt securities will be payable;
 
        (10) the period or periods within which, the events upon the occurrence
             of which, and the price and prices at which, we may redeem or
             purchase the debt securities, in whole or in part, pursuant to any
             optional or mandatory provisions;
 
        (11) our obligation, if any, to redeem or repurchase the debt securities
             at your option;
 
        (12) the denominations in which the debt securities will be issuable, if
             other than denominations of $1,000 and any integral multiple of
             $1,000;
 
        (13) the currency, currencies or currency unit or units of payment of
             principal of and any premium and interest on the debt securities if
             other than U.S. dollars;
 
        (14) any index or formula used to determine the amount of payments of
             principal of and any premium and interest on the debt securities;
 
        (15) a description of the terms, conditions and applicable periods for
             payment, if the principal amount of or any premium or interest on
             the debt securities is to be payable, at our election or at your
             election, in one or more currencies or currency units different
             from those stated in the debt securities;
 
        (16) the place or places where the debt securities may be presented for
             exchange, registration of transfer or, if applicable, conversion;
 
        (17) if other than the entire principal amount, the portion of the
             principal amount of the debt securities of the series that will be
             payable upon declaration of the acceleration of the maturity
             thereof;
 
        (18) with respect to any senior debt securities, the applicability of
             any provisions described under "Provisions of the Senior
             Indenture -- Certain Covenants of the Company";
 
        (19) the applicability of any provisions described under "Defeasance";
 
        (20) the terms and conditions, if any, pursuant to which the debt
             securities are convertible or exchangeable into common stock or
             other securities or instruments; and
 
        (21) any other terms of the debt securities consistent with the
             provisions of the applicable indenture.
 
     We may issue debt securities at a discount from their principal amount. If
applicable, the prospectus supplement will describe any United States federal
income tax considerations and other special considerations applicable to any
original issue discount securities.
 
     If the purchase price of any debt securities is denominated in one or more
foreign currencies or foreign currency units or if the principal amount of and
any premium and interest on any series of debt securities is payable in foreign
currencies or foreign currency units, then the applicable prospectus supplement
will describe the restrictions, elections, general tax considerations, specific
terms and other information with respect to that issue of debt securities.
 
                                        7

<PAGE>   9
 
             FORM, EXCHANGE, REGISTRATION, CONVERSION AND TRANSFER
 
     Debt securities are issuable in definitive form as registered debt
securities, as bearer debt securities or both. Unless otherwise indicated in an
applicable prospectus supplement, bearer debt securities will have interest
coupons attached. Debt securities are also issuable in temporary or permanent
global form.
 
     You will be permitted to exchange registered debt securities of any series
for different authorized denominations of the same series. In addition, subject
to the terms of the indenture, you will be permitted to exchange any bearer debt
securities (with all unmatured coupons, except as provided below, and all
matured coupons in default) into registered debt securities of the same series
of any authorized denominations. Bearer debt securities surrendered in exchange
for registered debt securities between a regular record date or a special record
date and the relevant date for payment of interest will be surrendered without
the interest coupon relating to that date, and interest accrued as of that date
will not be payable in respect of the registered debt security issued in
exchange for the bearer debt security, but will be payable only to the holder of
the interest coupon when due in accordance with the terms of the indenture.
 
     In connection with its sale during the restricted period (as defined
below), no bearer debt security (including a debt security in permanent global
form that is either a bearer debt security or exchangeable for bearer debt
securities) may be mailed or otherwise delivered to any location in the United
States (as defined under "-- Limitations on Issuance of Bearer Debt Securities")
and a bearer debt security may be delivered outside the United States in
definitive form in connection with its original issuance only if prior to
delivery the person entitled to receive the bearer debt security furnishes
written certification, in the form required by the indenture, to the effect that
the bearer debt security is owned by:
 
        (1) a person (purchasing for its own account) who is not a United States
            person (as defined under "-- Limitations on Issuance of Bearer Debt
            Securities");
 
        (2) a United States person who (a) is a foreign branch of a United
            States financial institution purchasing for its own account or for
            resale or (b) acquired the bearer debt security through the foreign
            branch of a United States financial institution and who for purposes
            of the certification holds the bearer debt security through that
            financial institution on the date of certification and, in either
            case, the United States financial institution certifies to us or the
            distributor selling the bearer debt security within a reasonable
            time stating that it agrees to comply with the requirements of
            Section 165(j)(3)(A), (B) or (C) of the United States Internal
            Revenue Code of 1986, as amended, and related regulations; or
 
        (3) a United States or foreign financial institution for purposes of
            resale within the "restricted period" as defined in United States
            Treasury Regulations Section 1.163-5(c)(2)(i)(D)(7).
 
     A financial institution described in clause (3) of the preceding sentence
(whether or not also described in clauses (1) and (2)) must certify that it has
not acquired the bearer debt security for purpose of resale, directly or
indirectly, to a United States person or to a person within the United States or
its possessions. In the case of a bearer debt security in permanent global form,
the certification must be given when a beneficial owner's interest in the
security is recorded in connection with the original issuance of the debt
security or upon exchange of a portion of a temporary global debt security.
 
     Debt securities may be presented for exchange as provided above, and
registered debt securities may be presented for registration or transfer (with
the accompanying form of transfer duly executed), at our office or agency
maintained for that purpose. Registered debt securities may also be presented
for registration or transfer at any other office or agency maintained for that
purpose with respect to any specific series of debt securities as described in
the applicable prospectus supplement. In either case you will not be required to
pay a service charge, but you will be required to pay any taxes and other
governmental charges as described in the indenture. We or our agent, as the case
may be, will complete the transfer or exchange when we or they are satisfied
with the documents of title and identity of the person making the request.
 
                                        8

<PAGE>   10
 
     In the event of any redemption in part, we will not be required to:
 
        (1) issue, register the transfer of or exchange debt securities of any
            series during a period beginning at the opening of business 15 days
            prior to the selection of debt securities of that series for
            redemption and ending on the close of business on (a) if debt
            securities of the series are issued only as registered debt
            securities, the day of mailing of the relevant notice of redemption
            and (b) if debt securities of the series are issued as bearer debt
            securities, the day of the first publication of the relevant notice
            of redemption or, if securities of the series are also issued as
            registered debt securities and there is no publication, the day of
            mailing of the relevant notice of redemption;
 
        (2) register the transfer of or exchange any registered debt security,
            or portion thereof, called for redemption, except the unredeemed
            portion of any registered debt security being redeemed in part; or
 
        (3) exchange any bearer debt security called for redemption, except to
            exchange a bearer debt security for a registered debt security of
            that series which is simultaneously surrendered for redemption.
 
                           PAYMENT AND PAYING AGENTS
 
     Unless otherwise indicated in the applicable prospectus supplement, the
principal of (and any premium) and interest on bearer debt securities will be
payable, subject to any applicable laws and regulations, in the designated
currency or currency unit, at the offices of such paying agents outside the
United States as we may designate from time to time. The payment will be made,
at your option, by check or by transfer to an account maintained by you with a
bank located outside the United States; provided, however, that you have
delivered the written certification described above under "-- Form, Exchange,
Registration, Conversion and Transfer" prior to the first actual payment of
interest. Unless otherwise indicated in the applicable prospectus supplement,
payment of interest on bearer debt securities on any interest payment date will
be made only against surrender to the paying agent of the coupon relating to
that interest payment date. We and our paying agents will not make payment with
respect to any bearer debt security at any office or agency of Noble Affiliates
in the United States or by check mailed to any address in the United States or
by transfer to any account maintained with a bank located in the United States,
nor will we make any payments in respect of bearer debt securities presented to
us or any of our paying agents within the United States. Notwithstanding the
foregoing, our paying agent will pay the principal of, premium, if any, and
interest on bearer debt securities denominated and payable in U.S. dollars at
its office in the United States, if, but only if, payment of the full amount in
U.S. dollars at all offices or agencies outside the United States is illegal or
effectively precluded by exchange controls or other similar restrictions.
 
     Unless otherwise indicated in the applicable prospectus supplement, we will
pay the principal of, premium, if any, and interest on registered debt
securities in the designated currency or currency unit at the office of such
paying agent or paying agents as we may designate from time to time, except that
at our option we may pay any interest by mailing a check to you at your address
listed in the security register. Unless otherwise indicated in an applicable
prospectus supplement, we will pay any installment of interest on registered
debt securities to the person in whose name the registered debt security is
registered at the close of business on the regular record date.
 
     Unless otherwise indicated in the applicable prospectus supplement, we will
designate the corporate trust office of the trustee under the applicable
indenture as a paying agent for payments with respect to debt securities that
are issuable solely as registered debt securities, and we will maintain a paying
agent outside the United States for payments with respect to debt securities,
subject to limitations described above in the case of bearer debt securities,
that are issued solely as bearer debt securities, or as both registered debt
securities and bearer debt securities. We will name in an applicable prospectus
supplement any paying agents outside the United States and any other paying
agents in the United States that we
 
                                        9

<PAGE>   11
 
initially designate for the debt securities. We may at any time designate
additional paying agents or rescind the designation of any paying agent or
approve a change in the office through which any paying agent acts, except that,
if we issue debt securities of a series solely as registered debt securities, we
will be required to maintain a paying agent in each place of payment for that
series and, if we issue debt securities of a series as bearer securities, we
will be required to maintain both:
 
        (1) a paying agent in the United States for principal payments with
            respect to any registered debt securities of the series (and for
            payments with respect to bearer debt securities of the series in the
            circumstances described above, but not otherwise), and
 
        (2) a paying agent in a place of payment outside the United States where
            securities of the series and any related interest coupons may be
            presented for payment.
 
     All monies that we deliver to a paying agent for the payment of principal
of and any premium or interest on any debt security that remain unclaimed at the
end of two years after the principal, premium or interest shall have become due
and payable will, subject to applicable escheat laws, be repaid to us, and the
holder of the debt security or any coupon will thereafter look only to us for
payment.
 
                          TEMPORARY GLOBAL SECURITIES
 
     If specified in the applicable prospectus supplement, all or any portion of
the debt securities of a series issuable as bearer debt securities will
initially be represented by one or more temporary global debt securities,
without interest coupon, to be deposited with a common depository in London for
Euroclear System and CEDEL S.A. for credit to the designated accounts. On and
after the date provided in the temporary global debt security and described in
the applicable prospectus supplement, each temporary global debt security will
be exchangeable for definitive bearer debt securities, definitive registered
debt securities or all or a portion of a permanent global security, or any
combination of the foregoing but, unless otherwise specified in the applicable
prospectus supplement, only upon written certification in the form and to the
effect described under "-- Form, Exchange, Registration, Conversion and
Transfer." No bearer debt security delivered in exchange for a portion of a
temporary global debt security will be mailed or otherwise delivered to any
location in the United States in connection with the exchange.
 
     Unless otherwise specified in the applicable prospectus supplement, we will
pay interest on any portion of a temporary global debt security, in respect of
any interest payment date occurring before the issuance of definitive debt
securities or a permanent global debt security, to each of Euroclear and CEDEL
with respect to the portion of the temporary global debt security held for its
account. Each of Euroclear and CEDEL will undertake in these circumstances to
credit the interest received by it to the respective accounts for which it holds
the temporary global debt security, in each case only upon receipt of
appropriate written certifications in the form and to the effect described above
under "-- Form, Exchange, Registration, Conversion and Transfer."
 
                          PERMANENT GLOBAL SECURITIES
 
     If any debt securities of a series are issuable in permanent global form,
the applicable prospectus supplement will describe the circumstances, if any,
under which beneficial owners of interests in any permanent global debt
securities may exchange the interests for debt securities of the series in any
authorized form and denomination. We and our paying agents will not mail or
otherwise deliver to any location in the United States any bearer debt security
delivered in exchange for a portion of a permanent global debt security.
 
                                       10

<PAGE>   12
 
                           BOOK-ENTRY DEBT SECURITIES
 
     We may issue the debt securities of a series in whole or in part in the
form of one or more global securities that will be deposited with, or on behalf
of, a depositary or its nominee identified in the applicable prospectus
supplement. In that case, we will issue one or more global securities in a
denomination or aggregate denominations equal to the portion of the aggregate
principal amount of outstanding debt securities of the series to be represented
by the global security or securities. Unless it is exchanged in whole or in part
for debt securities in registered form, a global security may not be registered
for transfer or exchange except as a whole among the depositary, a nominee of
the depositary or a successor depositary and except in the circumstances
described in the applicable prospectus supplement. (Sections 305 and 312)
 
     We will describe the specific terms of the depositary arrangement with
respect to any portion of a series of debt securities to be represented by a
global security in the applicable prospectus supplement. We expect that the
following provisions will apply to depositary arrangements.
 
     Unless otherwise specified in the applicable prospectus supplement, debt
securities represented by a global security to be deposited with or on behalf of
a depositary will be represented by a global security registered in the name of
the depositary or its nominee. Upon the issuance of the global security, and the
deposit of the global security with or on behalf of the depositary, the
depositary will credit, on its book-entry registration and transfer system, the
respective principal amounts of the debt securities represented by the global
security to the accounts of institutions that have accounts with the depositary
or its nominee (these institutions are referred to as "participants"). The
accounts to be credited will be designated by the underwriters or agents of the
debt securities or by us, if we offer and sell the debt securities directly.
Ownership of beneficial interests in the global security will be limited to
participants or persons that may hold interests through participants. Ownership
of beneficial interests by participants in the global security will be shown on,
and the transfer of that ownership interest will be effected only through,
records maintained by the depositary or its nominee for the global security.
Ownership of beneficial interests in the global security by persons that hold
through participants will be shown on, and the transfer of that ownership
interest within the participant will be effected only through, records
maintained by the participant. The laws of some jurisdictions require that
certain purchasers of securities take physical delivery of the securities in
certificated form. The foregoing limitations and those laws may impair the
ability to transfer beneficial interests in global securities.
 
     So long as the depositary for a global security, or its nominee, is the
registered owner of the global security, the depositary or its nominee, as the
case may be, will be considered the sole owner or holder of the securities
represented by that global security for all purposes under the applicable
indenture. Unless otherwise specified in the applicable prospectus supplement,
owners of beneficial interests in that global security will not be entitled to
have debt securities of the series represented by that global security
registered in their names, will not be entitled to receive physical delivery of
debt securities of that series in certificated form and will not be considered
the holders of those debt securities for any purposes under the applicable
indenture. (Sections 305 and 312) Accordingly, each person owning a beneficial
interest in a global security must rely on the procedures of the depositary and,
if that person is not a participant, on the procedures of the participant
through which the person owns its interest, to exercise any rights of a holder
under the applicable indenture. We understand that under existing industry
practices, if we request any action of holders or an owner of a beneficial
interest in a global security desires to give any notice or take any action a
holder is entitled to give or take under an indenture, the depositary would
authorize the participants to give notice or take action, and participants would
authorize beneficial owners owning through them to give notice or take action or
would otherwise act upon the instructions of beneficial owners owning through
them.
 
     Principal of and any premium and interest on a global security will be
payable in the manner described in the applicable prospectus supplement.
 
                                       11

<PAGE>   13
 
               LIMITATIONS ON ISSUANCE OF BEARER DEBT SECURITIES
 
     In compliance with United States federal tax laws and regulations, we will
not offer or sell bearer debt securities, including securities in permanent
global form that are either bearer debt securities or exchangeable for bearer
debt securities, during the restricted period within the United States or to
United States persons, each as defined below, other than to an office that:
 
        (1) is located outside the United States of a United States financial
            institution (as defined in Section 1.165-12(c)(1)(v) of the United
            States Treasury Regulations),
 
        (2) is purchasing for its own account or for resale or for the account
            of certain customers, and
 
        (3) provides a certificate stating that it agrees to comply with the
            requirements of Section 165(j)(3)(A), (B) or (C) of the Internal
            Revenue Code and the related United States Treasury Regulations
 
or to certain other persons described in Section 1.163-5(c)(2)(i)(D)(1)(iii)(B)
of the United States Treasury Regulations. The "restricted period" is defined in
United States Treasury Regulations Section 1.163-5(c)(2)(i)(D)(7) and generally
is the first 40 days after the closing of the securities offering, and with
respect to unsold allotments is until the securities are sold. Moreover, we will
not deliver bearer debt securities in connection with a sale by others during
the restricted period within the United States. Any underwriters and dealers
participating in the offering of bearer debt securities must agree that they
will not offer or sell during the restricted period any bearer debt securities
within the United States or to United States persons, other than the persons
described above, or deliver in connection with the sale of bearer debt
securities during the restricted period any bearer debt securities within the
United States. The underwriters and dealers must also agree to maintain
procedures reasonably designed to ensure that their employees and agents who are
directly engaged in selling the bearer debt securities are aware of the
restrictions described above. We will not deliver any bearer debt security,
other than a temporary global bearer debt security, in connection with its
original issuance nor will we pay interest on any bearer debt security until we
receive the written certification described above under "-- Form, Exchange,
Registration, Conversion and Transfer." Each bearer debt security, other than a
temporary global bearer debt security, will bear a legend to the following
effect: "Any United States person who holds this obligation will be subject to
limitations under the United States federal income tax laws, including the
limitations provided in Section 165(j) and 1287(a) of the Internal Revenue
Code."
 
     As used in this discussion, "United States person" means any citizen or
resident of the United States, any corporation, partnership or other entity
created or organized in or under the laws of the United States and any estate or
trust the income of which is subject to United States federal income taxation
regardless of its source, and "United States" means the United States of America
(including the states and the District of Columbia) and its possessions.
 
                             DEFAULTS AND REMEDIES
 
     Each of the following is an Event of Default, as more specifically defined
in the indentures, with respect to debt securities of any series:
 
        (1) our failure to pay principal or premium, if any, on any debt
            security of that series when due;
 
        (2) our failure to pay any interest due on any debt security of that
            series for 30 days;
 
        (3) our failure to make any sinking fund payment, when due, in respect
            of any debt security of that series;
 
        (4) our failure for 60 days after written notice to us to comply with
            any of our other covenants in the indenture;
 
        (5) default by us or any Restricted Subsidiary (defined below under
            "-- Certain Definitions") under any instrument or other evidence of
            indebtedness for money borrowed, or any
 
                                       12

<PAGE>   14
 
            guarantee of payment by us or any Restricted Subsidiary for money
            borrowed, in an amount in excess of five percent of Consolidated Net
            Tangible Assets (defined below under "-- Certain Definitions"),
            unless the default has been cured or waived;
 
          (6) certain events of bankruptcy, insolvency or reorganization
              relative to us or any Restricted Subsidiary; and
 
          (7) any other Events of Default provided with respect to debt
              securities of that series as described in the applicable
              prospectus supplement. (Section 501)
 
     If an Event of Default with respect to outstanding debt securities of any
series occurs and is continuing, either the trustee or holders of at least 25
percent in aggregate principal amount of the debt securities of that series then
outstanding may declare the principal amount of all debt securities of that
series and the accrued interest to be due and payable immediately. However,
under certain conditions, the acceleration may be rescinded by holders of a
majority in principal amount of the debt securities of that series then
outstanding. (Section 502)
 
     You will not be able to enforce the applicable indenture except as provided
in that indenture but, subject to any applicable subordination provisions,
nothing shall prevent holders of debt securities of any series from enforcing
payment of the principal of or premium, if any, or interest on, or, if
applicable, conversion of, their debt securities. Each trustee may refuse to
enforce an applicable indenture unless it receives reasonable security or
indemnity. Subject to certain limitations, holders of a majority in principal
amount of the debt securities of any series under an applicable indenture may
direct the trustee in its exercise of any trust or power under that indenture.
(Sections 508, 512 and 514)
 
     We will furnish the trustees with an officers' certificate with respect to
compliance with the terms of the applicable indenture. (Section 1005 of the
subordinated indenture and Section 1006 of the senior indenture)
 
                                  MODIFICATION
 
     We and the trustee may modify and amend an indenture with the consent of
the holders of a majority in aggregate principal amount of the debt securities
of each affected series then outstanding. However, no modification or amendment
may, without the consent of each affected holder:
 
          (1) reduce the rate or change the time or place for payment of
              principal or interest on any debt security;
 
          (2) reduce the principal of or rate of interest on, or the premium, if
              any, payable upon the redemption of, or change the fixed maturity
              of, any debt security;
 
          (3) make any debt security payable in a currency other than that
              stated in the debt security;
 
          (4) impair the right to institute suit for the enforcement of any
              payment on or with respect to any debt security;
 
          (5) make any change that adversely affects the right of a holder to
              convert any convertible debt security;
 
          (6) in the case of the subordinated indenture, modify the
              subordination provisions in a manner adverse to holders; or
 
          (7) reduce the amount of debt securities of any series whose holders
              must consent to modification or amendment of or waiver of
              compliance with certain provisions of the applicable indenture.
 
                                       13

<PAGE>   15
 
The indentures also contain provisions permitting us and the trustees to make
certain minor modifications to the applicable indentures not adversely affecting
your rights as a holder in any material respect. (Sections 901 and 902)
 
                    CONSOLIDATION, MERGER AND SALE OF ASSETS
 
     We generally may consolidate or merge with or into any person, or convey,
transfer, lease or otherwise dispose of our assets. Likewise, any person may
consolidate or merge with or into, or transfer or lease its assets to, us.
However, no transaction of those types may occur unless:
 
          (1) the person (if other than us) formed by the consolidation or into
              which we are merged or that acquires or leases our assets is
              organized and existing under the laws of the United States, any
              state thereof or the District of Columbia, and assumes our
              obligations on the debt securities and under the applicable
              indentures;
 
          (2) after giving effect to the transaction, no Event of Default and no
              event that, after notice or lapse of time or both, would become an
              Event of Default, shall have happened and be continuing; and
 
          (3) certain other conditions are met. (Section 801)
 
                                   DEFEASANCE
 
     Subject to compliance with certain conditions, we may discharge our
indebtedness and our obligations or certain of our obligations under the
applicable indenture by depositing funds or obligations issued or guaranteed by
the United States of America with the applicable trustee.
 
     Defeasance and Discharge. The applicable indenture will provide that we
will be discharged from any and all obligations in respect of debt securities of
a series being defeased, except for:
 
          (1) certain obligations relating to temporary debt securities of the
              series and exchange of debt securities of the series,
 
          (2) registration of transfer or exchange of debt securities of the
              series,
 
          (3) replacement of stolen, lost or mutilated debt securities of the
              series, and
 
          (4) maintenance of paying agencies to hold monies for payment in trust
              and payment of United States withholding taxes, if any, imposed on
              payments to non-United States persons,
 
if we deposit with the applicable trustee, in trust, money and/or U.S.
government obligations that, through the payment of interest and principal on
the amounts deposited, will provide money in an amount sufficient to pay the
principal of and premium, if any, and each installment of interest on, the debt
securities of that series on the stated maturity dates in accordance with the
terms of the applicable indenture and the debt securities of the series.
(Sections 1502 and 1504 of the subordinated indenture and Sections 1302 and 1304
of the senior indenture) We may establish the trust only if, among other things,
we have delivered to the applicable trustee an opinion of counsel confirming
that:
 
          (1) we have received from, or there has been published by, the
              Internal Revenue Service a ruling, or
 
          (2) since the date of the applicable indenture there has been a change
              in the applicable federal income tax law,
 
in either case to the effect that holders of the securities will not recognize
income, gain or loss for federal income tax purposes as a result of the deposit,
defeasance and discharge, and will be subject to federal income tax on the same
amounts and in the same manner and at the same times as would have been the case
if the deposit, defeasance and discharge had not occurred. (Section 1504 of the
subordinated
 
                                       14

<PAGE>   16
 
indenture and Section 1304 of the senior indenture) In the event of any
defeasance and discharge of debt securities of a series, you would be entitled
to look only to the trust fund for payment of principal of and any premium and
interest on your debt securities until maturity.
 
     Defeasance of Certain Obligations. The indentures will provide that we may
omit to comply with certain restrictive covenants, including the covenants
described under "Provisions Applicable to the Senior Indenture -- Certain
Covenants of the Company" below and that the omission shall not be an Event of
Default with respect to the debt securities of a particular series. This right
is commonly known as covenant defeasance, and it would require us to deposit
with the applicable trustee, in trust, money and/or U.S. government obligations
that, through the payment of interest and principal on the amounts deposited,
would provide enough money to pay the principal of and premium, if any, and each
installment of interest on, the debt securities of that series on the stated
maturity dates in accordance with the terms of the applicable indenture and the
debt securities of that series. Our other obligations under the applicable
indenture and the debt securities of that series would remain in full force and
effect. (Section 1503 and 1504) We may effect a covenant defeasance only if,
among other things, we have delivered to the applicable trustee an opinion of
counsel to the effect that holders of the securities will not recognize income,
gain or loss for federal income tax purposes as a result of the deposit and
defeasance, and will be subject to federal income tax on the same amounts and in
the same manner and at the same times as would have been the case if the deposit
and defeasance had not occurred. (Section 1504 of the subordinated indenture and
Section 1304 of the senior indenture)
 
     The amount of money and U.S. government obligations on deposit with the
applicable trustee would be intended to be sufficient to pay amounts due on the
debt securities of the series at the time of their stated maturity. However, if
the debt securities of that series are declared due and payable because of the
occurrence of any Event of Default, the deposited amount may not be sufficient
to pay amounts due on the debt securities of that series at the time of the
acceleration resulting from the Event of Default. We will in any event remain
liable for those payments as provided in the applicable indenture.
 
                                 GOVERNING LAW
 
     The debt securities and the indentures provide that they are governed by
the laws of the State of New York, without regard to the principles of conflicts
of laws. (Section 112)
 
                            CONCERNING THE TRUSTEES
 
     If the trustee were to become a creditor of Noble Affiliates, each
indenture contains certain limitations on the rights of the trustee to obtain
payment of claims in certain cases, or to realize on certain property received
in respect of any claim as security or otherwise. (Section 613) Each trustee
will be permitted to engage in other transactions with us. However, if it
acquires any conflicting interest (as defined) and there exists a default with
respect to the debt securities of any series outstanding under the applicable
indenture, it must eliminate the conflicting interest or resign. (Section 608)
 
     The holders of a majority in aggregate principal amount of outstanding debt
securities under an indenture will have the right to direct the time, method and
place of conducting any proceeding for exercising any remedy or power available
to the trustee under the indenture. However, they will have the right to do so
only if their directions do not conflict with any law or with the applicable
indenture and would not involve the trustee in personal liability or be unduly
prejudicial to holders not joining in the action, as determined by the trustee
in good faith. (Section 512)
 
     If a default or an Event of Default under an indenture occurs and is
continuing and is known to the trustee under the indenture, the trustee must
mail to each holder of debt securities of the affected series notice of the
default or Event of Default within 90 days after it occurs. Except in the case
of a default or an Event of Default in payment of the principal of, or premium,
if any, or interest on, any debt security of any series, the trustee may
withhold the notice so long as the trustee in good faith determines that
withholding the notice is in the interest of the holders of debt securities of
that series under the indenture.
                                       15

<PAGE>   17
 
When a trustee incurs expenses or renders services after an Event of Default,
the expenses and the compensation for the services are intended to constitute
expenses of administration under any bankruptcy law. (Section 602)
 
PROVISIONS APPLICABLE TO THE SENIOR INDENTURE
 
     The senior debt securities will rank equally with all of our other
unsubordinated and unsecured indebtedness and senior to the subordinated debt
securities and all of our other subordinated debt.
 
                        CERTAIN COVENANTS OF THE COMPANY
 
     Please refer to the definitions provided below regarding certain
capitalized terms used in this section.
 
     If indicated in the applicable prospectus supplement with respect to a
particular series of senior debt securities, we will be subject to either or
both of the following covenants titled "Limitations on Liens" and "Limitations
on Sale and Leaseback Transactions" or any other covenants indicated in the
prospectus supplement:
 
     Limitations on Liens. If Noble Affiliates or a Restricted Subsidiary
incurs, assumes or guarantees a debt secured by a Mortgage either on any Mineral
Interest or on a Restricted Subsidiary's stock or debt, we will secure the debt
securities on at least an equal basis. These restrictions do not apply to debt
secured by the following:
 
          (1) Mortgages in existence on the date of the applicable indenture;
 
          (2) Mortgages affecting Mineral Interests, shares of capital stock or
              debt of an entity existing at the time it becomes a subsidiary or
              at the time it is merged into or consolidated with us or a
              subsidiary, or on any shares of capital stock or debt of any
              Restricted Subsidiary at the time its becomes a Restricted
              Subsidiary;
 
          (3) Mortgages on property existing when we acquire the property, or
              Mortgages on any property that we or any Restricted Subsidiary
              acquires after the date of the applicable indenture that are
              created or assumed to secure the payment of all or any part of the
              purchase price of the property or to secure any debt incurred
              prior to, at the time of, or within 120 days after the acquisition
              of the property for the purpose of financing all or any part of
              its purchase price;
 
          (4) Mortgages on property constructed or improved after the date of
              the applicable indenture by us or any Restricted Subsidiary that
              are created or assumed to secure the payment of all or any part of
              the cost of the construction or improvement, provided, however,
              that any Mortgage of this kind shall not apply to any property
              owned by us or any Restricted Subsidiary prior to the date of the
              applicable indenture;
 
          (5) Mortgages on our property or the property of a Restricted
              Subsidiary to secure the payment of all or any part of the costs
              incurred after the date of the applicable indenture of
              exploration, drilling, mining or development of the property for
              the purposes of increasing the production and sale of oil, gas and
              other minerals, or any debt incurred to provide funds for all or
              any of those purposes;
 
          (6) Mortgages that secure only debt of a Restricted Subsidiary owed to
              us or to another Restricted Subsidiary;
 
          (7) Mortgages in favor of the United States or any state or
              governmental instrumentality thereof securing payments pursuant to
              any contract or statute or to secure any indebtedness incurred for
              the purpose of financing all or any part of the purchase price or
              cost of constructing or improving the property subject to the
              Mortgages; and
 
                                       16

<PAGE>   18
 
          (8) any extension, renewal or replacement, in whole or in part, of any
              of the Mortgages referred to in the foregoing clauses (1) through
              (7), inclusive, or of any debt secured by those Mortgages.
              (Section 1004)
 
     Notwithstanding the foregoing, Noble Affiliates or a Restricted Subsidiary
may issue, assume or guarantee debt secured by Mortgages if such debt, when
added to all other debt that would otherwise be restricted by the foregoing (but
not including debt permitted under items (1) through (8) above), does not at any
time exceed ten percent of the Consolidated Net Tangible Assets of Noble
Affiliates and its Restricted Subsidiaries.
 
     Under the terms of the senior indenture, the sale or transfer of (1) oil,
gas or other minerals in place for a period of time only, or in an amount such
that the transferee will realize only a specified amount of money (however
determined) or a specified amount of oil, gas and other minerals or (2) any
other interest in property of the character commonly referred to as a
"production payment," will not be deemed to create debt secured by a Mortgage.
 
     Limitations on Sale and Leaseback Transactions. The senior indenture
provides that neither we nor any Restricted Subsidiary will enter into any Sale
and Leaseback Transaction with any person, other than us or a Restricted
Subsidiary, unless:
 
          (1) we or the Restricted Subsidiary would be entitled to incur
              indebtedness in a principal amount equal to the Attributable Debt
              with respect to the Sale and Leaseback Transaction, secured by a
              Mortgage on the property subject to the Sale and Leaseback
              Transaction pursuant to the provisions described under
              "-- Limitations on Liens" above without equally and ratably
              securing the senior debt securities;
 
          (2) after the date on which the senior debt securities are originally
              issued and within a period commencing 180 days before and ending
              180 days after the consummation of the Sale and Leaseback
              Transaction, we or the Restricted Subsidiary shall have expended
              for property used or to be used in the ordinary course of
              business -- including amounts expended for the acquisition,
              exploration, drilling and development thereof, and for additions,
              alterations, repairs and improvements thereto -- an amount equal
              to all or a portion of the net proceeds of the Sale and Leaseback
              Transaction and we shall have elected to designate the amount as a
              credit against the Sale and Leaseback Transaction (with any amount
              not being so designated to be applied in clause (3) below); or
 
          (3) we, during the 365-day period after the effective date of the Sale
              and Leaseback Transaction, shall have applied to the voluntary
              defeasance or retirement of any Senior Indebtedness an amount
              equal to the greater of (a) the net proceeds of the sale or
              transfer of the property leased in the Sale and Leaseback
              Transaction and (b) the fair value, as determined by our Board of
              Directors, of that property at the time of entering into the Sale
              and Leaseback Transaction (in either case adjusted to reflect the
              remaining term of the lease and any amount expended by us or any
              Restricted Subsidiary as set forth in clause (2) above), less an
              amount equal to the principal amount of Senior Indebtedness
              voluntarily defeased or retired by us within the 365-day period
              and not designated as a credit against any other Sale and
              Leaseback Transaction entered into by us or any Restricted
              Subsidiary during that period. (Section 1005)
 
                                       17

<PAGE>   19
 
                              CERTAIN DEFINITIONS
 
     The senior indenture contains definitions of certain terms used in the
indenture, including the following:
 
     "Attributable Debt" means, when used with respect to any Sale and Leaseback
Transaction, as of the time of determination, the present value (discounted at a
rate equal to our then current weighted average cost of funds for borrowed money
as of the time of determination, compounded on a semiannual basis) of the total
obligations of the lessee for rental payments during the remaining term of the
lease included in the Sale and Leaseback Transaction (including any period for
which the lease has been extended).
 
     "Consolidated Net Tangible Assets" means the total amount of assets
included in the consolidated balance sheet of Noble Affiliates and its
Restricted Subsidiaries (less depreciation, depletion, valuation and other
reserves) after deducting:
 
          (1) all current liabilities;
 
          (2) all goodwill, trade names, trademarks, patents, unamortized debt
              discount and expense and other like intangibles;
 
          (3) investments in and advances to subsidiaries that are not
              Restricted Subsidiaries; and
 
          (4) minority interests in the equity of Restricted Subsidiaries.
 
     "Hydrocarbons" means oil, gas and other liquid or gaseous hydrocarbons.
 
     "Mineral Interests" means leasehold and other interests of Noble Affiliates
or a Restricted Subsidiary in or under oil, gas or other mineral fee interests,
overriding royalty and royalty interests and any other interest in Hydrocarbons
and any other interest in minerals in place wherever located and classified by
our Board of Directors as capable of producing Hydrocarbons by us or a
Restricted Subsidiary, except any interest that in the opinion of our Board of
Directors is not of material importance to the total business conducted by Noble
Affiliates and its Restricted Subsidiaries.
 
     "Mortgage" means any mortgage, lien, security interest, pledge, charge or
other encumbrance.
 
     "Restricted Subsidiary" means any subsidiary of Noble Affiliates the assets
of which comprise in excess of 15 percent of total consolidated assets of Noble
Affiliates and its consolidated subsidiaries as included in the latest audited
consolidated balance sheet contained in the latest annual report sent to our
shareholders. As of June 30, 1999, Samedan Oil Corporation and Energy
Development Corporation were our only subsidiaries that would qualify as
Restricted Subsidiaries.
 
     "Sale and Leaseback Transaction" means any arrangement with any person
providing for the leasing to Noble Affiliates or any Restricted Subsidiary, for
a period of more than three years, of any real or tangible personal property
that has been, or is to be, sold or transferred by us or the Restricted
Subsidiary to the lessor in contemplation of the leasing.
 
     "Senior Indebtedness" means the principal of and premium, if any, and
unpaid interest on the following, whether outstanding at the date of the
applicable indenture or thereafter incurred or created:
 
          (1) our indebtedness for money borrowed (including purchase money
              obligations) evidenced by notes or other written obligations;
 
          (2) our indebtedness evidenced by notes, debentures, bonds or other
              securities issued under the provisions of an indenture or other
              similar instrument;
 
          (3) our obligations as lessee under capitalized leases and under
              leases of property made as part of any Sale and Leaseback
              Transaction;
 
          (4) our obligations in respect of letters of credit issued for our
              account and swaps of interest rates (and other interest rate
              hedging agreements) to which we are a party;
 
                                       18

<PAGE>   20
 
          (5) indebtedness of others of any kinds described in the preceding
              clauses (1) through (4) assumed or guaranteed by us; and
 
          (6) renewals, extensions and refundings of, and indebtedness and
              obligations of a successor person issued in exchange for or in
              replacement of, indebtedness or obligations of the kinds described
              in the preceding clauses (1) through (5).
 
However, the following is not Senior Indebtedness: (a) any indebtedness or
obligation referring explicitly to the subordinated debt securities or other
subordinated debt and stating that the indebtedness and obligation shall not be
senior in right of payment; (b) any of our indebtedness or obligations in
respect of the subordinated debt securities; and (c) any of our indebtedness or
obligations to a subsidiary.
 
PROVISIONS APPLICABLE TO THE SUBORDINATED INDENTURE
 
     The subordinated debt securities will rank junior to the senior debt
securities and all of our other unsecured and unsubordinated indebtedness and
will rank equally with all of our other subordinated debt.
 
                                 SUBORDINATION
 
     Payment of the principal of and premium, if any, and interest on the
subordinated debt securities will be subordinated in right of payment, as set
forth in the subordinated indenture, to the prior payment in full of all of our
Senior Indebtedness when due. (Section 1401)
 
     There are no restrictions in the subordinated indenture on the creation of
Senior Indebtedness.
 
     Because of the subordination, in the event of our dissolution, insolvency,
bankruptcy or other similar proceeding, you, as a holder of subordinated debt
securities, might recover less, ratably, than holders of Senior Indebtedness and
our other general creditors. Upon any distribution of our assets, the holders of
subordinated debt securities will be required to pay over their share of the
distribution to the holders of Senior Indebtedness until the Senior Indebtedness
is paid in full. In addition, if any subordinated debt securities are declared
due and payable prior to their stated maturity, or in the event of any default
in the payment of principal of or premium, if any, or interest on any Senior
Indebtedness beyond any applicable grace period, or in the event of any default
with respect to Senior Indebtedness that would permit acceleration of its
maturity, or if a judicial proceeding is pending with respect to any Senior
Indebtedness default, the holders of Senior Indebtedness will be entitled to be
paid in full before we may make any payments to the holders of subordinated debt
securities. (Sections 1401, 1402 and 1403)
 
                         DESCRIPTION OF PREFERRED STOCK
 
GENERAL
 
     Our certificate of incorporation authorizes our Board of Directors to cause
preferred stock to be issued in one or more series, without stockholder action.
The Board of Directors is authorized to issue up to 4,000,000 shares of
preferred stock, $1.00 par value per share, and can determine the number of
shares of each series, and the rights, preference and limitations of each
series. We may amend our certificate of incorporation to increase the number of
authorized shares of preferred stock in a manner permitted by the certificate of
incorporation and the Delaware General Corporation Law.
 
     The particular terms of any series of preferred stock being offered by us
under this shelf registration will be described in the prospectus supplement
relating to that series of preferred stock. Those terms may include:
 
         1. The number of shares of the series of preferred stock being offered;
 
         2. Voting rights, if any, of the series of preferred stock;
 
         3. The title and liquidation preference per share of that series of the
            preferred stock;
 
                                       19

<PAGE>   21
 
         4. The purchase price of the preferred stock;
 
         5. The dividend rate (or method for determining dividend rates);
 
         6. The dates on which dividends will be paid;
 
         7. Whether dividends on that series of preferred stock will be
            cumulative or noncumulative and, if cumulative, the dates from which
            dividends will begin to accumulate;
 
         8. Any redemption or sinking fund provisions applicable to that series
            of preferred stock;
 
         9. Any conversion provisions applicable to that series of preferred
            stock; and
 
        10. Any additional dividend, liquidation, redemption, sinking fund and
            other rights and restrictions applicable to that series of preferred
            stock.
 
     If the terms of any series of preferred stock being offered differ from the
terms set forth in this prospectus, we will describe those terms in the
prospectus supplement relating to that series of preferred stock. The following
summary is not complete. You should refer to the certificate of designations
relating to the series of the preferred stock for the complete terms of that
preferred stock. We will file that certificate of designations with the SEC as
an exhibit to our registration statement promptly after the offering of the
preferred stock.
 
     The preferred stock will, when issued, be fully paid and nonassessable.
Unless otherwise specified in the prospectus supplement, if we liquidate,
dissolve or wind-up our business, each series of preferred stock will have the
same rank as to dividends and distributions as each other series of the
preferred stock we may issue in the future. The preferred stock will have no
preemptive rights.
 
DIVIDEND RIGHTS
 
     Holders of preferred stock of each series will be entitled to receive,
when, as and if declared by the Board of Directors, cash dividends at the rates
and on the dates set forth in the prospectus supplement. Dividend rates may be
fixed or variable or both. Different series of preferred stock may be entitled
to dividends at different dividend rates or based upon different methods of
determination. Each dividend will be payable to the holders of record as they
appear on our stock books on record dates determined by the Board of Directors.
Dividends on any series of the preferred stock may be cumulative or
noncumulative, as specified in the prospectus supplement. If the Board of
Directors fails to declare a dividend on any series of preferred stock for which
dividends are noncumulative, then the right to receive that dividend will be
lost, and we will have no obligation to pay the dividend for that dividend
period, whether or not dividends are declared for any future dividend period.
 
     We may not declare or pay any full dividends on any series of preferred
stock, unless we have declared and paid, or contemporaneously declare and pay,
full dividends for the dividend period commencing after the immediately
preceding dividend payment date (and cumulative dividends still owing, if any)
on all other series of preferred stock that have the same rank as, or rank
senior to, that preferred stock. When we do not pay those dividends in full, we
will declare dividends pro rata, so that the amount of dividends declared per
share on that series of preferred stock and on each other series of preferred
stock having the same rank as, or ranking senior to, that series of preferred
stock will in all cases bear to each other the same ratio that accrued dividends
per share on that series of preferred stock and the other preferred stock bear
to each other. In addition, we generally may not declare or pay any dividends on
our common stock or redeem or purchase any common stock, unless we have paid
full dividends, including cumulative dividends still owing, if any, on all
outstanding shares of any series of preferred stock. We will not pay any
interest, or sum of money in lieu of interest, in connection with any dividend
payment or payments that may be in arrears.
 
     Unless otherwise described in the prospectus supplement, we will compute
the amount of dividends payable for each dividend period by annualizing the
applicable dividend rate and dividing by the number of dividend periods in a
year, except that we will compute the amount of dividends payable for the
initial
 
                                       20

<PAGE>   22
 
dividend period or any period shorter than a full dividend period on the basis
of a 360-day year consisting of twelve 30-day months and, for any period less
than a full month, the actual number of days elapsed in the period.
 
RIGHTS UPON LIQUIDATION
 
     If we liquidate, dissolve or wind-up our affairs, either voluntarily or
involuntarily, the holders of each series of preferred stock will be entitled to
receive liquidating distributions in the amount set forth in the prospectus
supplement relating to that series of preferred stock, plus an amount equal to
accrued and unpaid dividends, if any, before any distribution of assets is made
to the holders of common stock. If the amounts payable with respect to preferred
stock of any series and any stock having the same rank as that series of
preferred stock are not paid in full, the holders of preferred stock and of the
other stock will share ratably in any distribution of assets in proportion to
the full respective preferential amounts to which they are entitled. After the
holders of each series of preferred stock and any stock having the same rank as
the preferred stock are paid in full, they will have no right or claim to any of
our remaining assets. Neither the sale of all or substantially all our property
or business nor a merger or consolidation by us with any other corporation will
be considered a dissolution, liquidation or winding up of our business or
affairs.
 
REDEMPTION
 
     A series of preferred stock may be redeemable, in whole or in part, at our
option. In addition, any series of preferred stock may be subject to mandatory
redemption pursuant to a sinking fund. Any redemption provisions that apply to a
series of preferred stock, including the redemption dates and the redemption
prices for that series, will be set forth in the prospectus supplement.
 
     If a series of preferred stock is subject to mandatory redemption, the
prospectus supplement will specify the year we can begin to redeem shares of the
preferred stock, the number of shares of the preferred stock we can redeem each
year, and the redemption price per share. We may pay the redemption price in
cash, stock or in cash that we have received specifically from the sale of our
capital stock, as specified in the prospectus supplement. If the redemption
price is to be paid only from the proceeds of the sale of our capital stock, the
terms of the series of preferred stock may also provide that, if no capital
stock is sold or if the amount of cash received is insufficient to pay in full
the redemption price then due, the series of preferred stock will automatically
be converted into shares of the applicable capital stock pursuant to conversion
provisions specified in the prospectus supplement.
 
     If fewer than all the outstanding shares of any series of preferred stock
are to be redeemed, whether by mandatory or optional redemption, the Board of
Directors will determine the method for selecting the shares to be redeemed,
which may be by lot or pro rata or by any other method determined to be
equitable. From and after the redemption date, dividends will cease to accrue on
the shares of preferred stock called for redemption and all rights of the
holders of those shares (except the right to receive the redemption price) will
cease.
 
     If we have not paid full dividends, including accrued but unpaid dividends,
if any, on any series of preferred stock, we may not redeem that series in part
and we may not purchase or acquire any shares of that series of preferred stock,
except by any offer made on the same terms to all holders of that series of
preferred stock.
 
VOTING RIGHTS
 
     Except as indicated in this prospectus or in a prospectus supplement, or
except as expressly required by applicable law, the holders of preferred stock
will not be entitled to vote.
 
RIGHTS AGREEMENT
 
     We have adopted a Rights Agreement, which provides for the issuance of a
right (a "Right") to the holder of each of our shares of common stock. Because
this summary of the Rights Agreement is not
 
                                       21

<PAGE>   23
 
complete, we have provided and refer you to the Rights Agreement, as amended,
which is an exhibit to the registration statement containing this prospectus.
 
     Generally, if anyone acquires 15% or more of our outstanding common stock
(an "Acquiring Person"), each holder of a Right (other than the Acquiring
Person) will be entitled to purchase one one-hundredth of a share of our Series
A Junior Participating Preferred Stock, par value $1.00 per share ("Series A
Stock"), for $150.00. Otherwise, prior to an Acquiring Person acquiring 50% or
more of our outstanding common stock, we may elect to issue a share of our
common stock in exchange for each Right (other than Rights held by the Acquiring
Person). In addition, if we are acquired in a merger or other business
combination or 50% or more of our assets or earning power is sold, each holder
of a Right will be entitled to buy, at the exercise price, common stock of the
acquirer having a then current market value of two times the purchase price of
the Rights held by that holder. At any time before there is an Acquiring Person,
we can redeem the Rights in whole, but not in part, for $0.01 per Right.
 
     Generally, the Series A Stock will rank junior to all other preferred stock
regarding dividends and in liquidation. Each share of Series A Stock is entitled
to a minimum preferential quarterly dividend payment of $0.01 per share and
entitled to an aggregate dividend of 100 times the dividend declared on each
share of our common stock. In the event of liquidation, each holder of the
Series A Stock will be entitled to a minimum preferential liquidation payment of
$1.00 per share of Series A Stock held but will be entitled to an aggregate
payment, on account of each share of Series A Stock held, of 100 multiplied by
the payment made per share of our common stock. Each share of Series A Stock has
100 votes, voting together with our common stock. Finally, in the event of any
merger, consolidation or other transaction in which common stock is exchanged,
each share of Series A Stock will be entitled to receive 100 times the amount
received per share of our common stock. These rights are protected by customary
antidilution provisions.
 
     As of the date of this prospectus, there are no shares of Series A Stock
outstanding.
 
                          DESCRIPTION OF COMMON STOCK
 
     As of the date of this prospectus, we are authorized to issue up to
100,000,000 shares of common stock, par value $3.33 1/3 per share. As of June
30, 1999, we had 56,987,548 shares of common stock issued and outstanding.
 
     The following summary is not complete. You should refer to the applicable
provisions of our certificate of incorporation, including the certificates of
designations pursuant to which any outstanding series of preferred stock may be
issued, and the Delaware General Corporation Law for a complete statement of the
terms and rights of the common stock.
 
     Dividends. Holders of common stock are entitled to receive dividends when,
as and if declared by the Board of Directors, out of funds legally available for
their payment (subject to the rights of holders of the preferred stock, if any).
 
     Voting Rights. Each holder of common stock is entitled to one vote per
share. Subject to the rights, if any, of the holder of any series of preferred
stock pursuant to applicable law or the provisions of the certificate of
designations creating that series, all voting rights are vested in the holders
of shares of common stock.
 
     Rights Upon Liquidation. In the event of our voluntary or involuntary
liquidation, dissolution or winding up, the holders of common stock will be
entitled to share equally in any of our assets available for distribution after
the payment in full of all debts and distributions and after the holders of all
series of outstanding preferred stock, if any, have received their liquidation
preferences in full.
 
     Miscellaneous. The issued and outstanding shares of common stock are fully
paid and nonassessable. Holders of shares of common stock are not entitled to
preemptive rights. Shares of common stock are not convertible into shares of any
other class of capital stock. The approval of 75% of our outstanding voting
stock is required for a merger or consolidation or the sale of all or
substantially all of our assets.
 
                                       22

<PAGE>   24
 
                            DESCRIPTION OF WARRANTS
 
     We may issue warrants for the purchase of debt securities, preferred stock
or common stock. We may issue warrants independently or together with other
securities. We will issue each series of warrants under a separate warrant
agreement to be entered into between us and a bank or trust company, as warrant
agent. You should refer to the warrant agreement relating to the specific
warrants being offered for the complete terms of the warrant agreement and the
warrants.
 
     Each warrant will entitle the holder to purchase the principal amount of
debt securities, or the number of shares of preferred stock or common stock, at
the exercise price set forth in, or calculable as set forth in, the prospectus
supplement. The exercise price may be subject to adjustment upon the occurrence
of certain events, as set forth in the prospectus supplement. After the close of
business on the expiration date of the warrant, unexercised warrants will become
void. The place or places where, and the manner in which, warrants may be
exercised will be specified in the prospectus supplement.
 
                              PLAN OF DISTRIBUTION
 
     We may sell the offered securities through underwriters, dealers or agents,
or we may sell directly to one or more purchasers. The prospectus supplement
will name any underwriters, state the purchase price and the proceeds received
by us, any underwriting discounts and other items constituting underwriters'
compensation, the initial public offering price, any discounts or concessions to
dealers, and any securities exchanges on which the offered securities may be
listed.
 
     If underwriters are used in the sale, the underwriters will acquire the
offered securities for their own account. The underwriters may resell the
offered securities in one or more transactions, including negotiated
transactions, at a fixed public offering price or at varying prices determined
at the time of sale. The offered securities may be offered through an
underwriting syndicate represented by many underwriters. The obligations of the
underwriters to purchase the offered securities will be subject to certain
conditions. The underwriters will be obligated to purchase all the offered
securities if any are purchased. Any initial public offering price and any
discounts or concessions allowed or reallowed or paid to dealers may be changed
from time to time.
 
     These offered securities may be sold directly by us or through agents. Any
agent will be named, and any commissions payable to that agent will be set forth
in the prospectus supplement. Unless otherwise indicated in the prospectus
supplement, any agent will be acting on a best efforts basis.
 
     We may authorize agents, underwriters or dealers to solicit offers by
specified institutions to purchase offered securities pursuant to delayed
delivery contracts providing for payment and delivery on a specified date in the
future. These contracts will be subject only to those conditions set forth in
the prospectus supplement. The prospectus supplement will set forth the
commission payable for soliciting delayed delivery contracts.
 
     We may agree to indemnify underwriters, dealers or agents against certain
civil liabilities, including liabilities under the Securities Act of 1933, and
may also agree to contribute to payments that the underwriters, dealers or
agents may be required to make.
 
                                 LEGAL MATTERS
 
     Thompson & Knight, P.C., of Dallas, Texas will issue an opinion about the
legality of the securities for us. Any underwriters will be advised about issues
relating to this offering by their own legal counsel. Harold F. Kleinman, a
shareholder of Thompson & Knight, P.C., is one of our directors and is the
beneficial owner of 1,000 shares of common stock.
 
                                       23

<PAGE>   25
 
                                    EXPERTS
 
     The financial statements and schedules incorporated by reference in this
prospectus and elsewhere in the registration statement have been audited by
Arthur Andersen LLP, independent public accountants, as indicated in their
reports with respect thereto, and are included herein in reliance upon the
authority of said firm as experts in giving said reports.
 
                                       24

<PAGE>   26
 

                                    PART II
 
                     INFORMATION NOT REQUIRED IN PROSPECTUS
 
ITEM 14. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.
 
     The estimated expenses payable by us in connection with the offering
described in this Registration Statement (other than underwriting discounts and
commissions) are as follows:
 

<TABLE>
<S>                                                            <C>
SEC Registration Fee........................................   $222,400
Printing and Engraving Expenses.............................    100,000
Accounting Fees and Expenses................................    100,000
Legal Fees and Expenses.....................................    150,000
Blue Sky Qualification Fees and Expenses....................     15,000
Trustee's Fees..............................................     10,000
Fees of Rating Agencies.....................................    100,000
Miscellaneous...............................................     30,000
                                                               --------
          TOTAL.............................................   $727,400
                                                               ========
</TABLE>

 
ITEM 15. INDEMNIFICATION OF DIRECTORS AND OFFICERS.
 
     Article VI of our by-laws, as amended, provides for indemnification of
officers and directors of Noble Affiliates, Inc., as well as its employees if
desired, to the extent authorized by the Delaware General Corporation Law.
Pursuant to Section 145 of the Delaware General Corporation Law, a Delaware
corporation generally has the power to indemnify its present and former
directors, officers, employees and agents against expenses incurred by them in
connection with any suit to which they are, or are threatened to be made, a
party by reason of their serving in those positions so long as they acted in
good faith and in a manner they reasonably believed to be in, or not opposed to,
the best interests of the corporation, and with respect to any criminal action,
they had no reasonable cause to believe their conduct was unlawful. With respect
to suits by or in the right of a corporation, however, indemnification is not
available if the person is adjudged to be liable for negligence or misconduct in
the performance of his duty to the corporation unless the court determines that
indemnification is appropriate. In addition, a corporation has the power to
purchase and maintain insurance for those persons. The statute also expressly
provides that the power to indemnify is not exclusive of any rights granted
under any bylaw, agreement, vote of stockholders or disinterested directors, or
otherwise.
 
     The above discussion of our by-laws and of Section 145 of the Delaware
General Corporation Law is not intended to be exhaustive and is qualified in its
entirety by our by-laws and by statute.
 
     Any underwriting agreement or agency agreement with respect to an offering
of securities registered by this Registration Statement will provide for
indemnification of Noble Affiliates, Inc. and its officers and directors by the
underwriters or agents, as the case may be, against certain liabilities,
including liabilities under the Securities Act of 1933.
 
                                      II-1

<PAGE>   27
 
ITEM 16. EXHIBITS.
 

<TABLE>
<CAPTION>
        EXHIBIT
         NUMBER
        -------
<C>                      <S>
           4.1           -- Indenture dated as of October 14, 1993 between the
                            Company and U.S. Trust Company of Texas, N.A., as
                            Trustee, relating to the Company's 7 1/4% Notes Due 2023,
                            including form of the Company's 7 1/4% Notes Due 2023
                            (filed as Exhibit 4.1 to the Company's Quarterly Report
                            on Form 10-Q for the quarter ended September 30, 1993 and
                            incorporated herein by reference).
           4.2           -- Indenture relating to senior debt securities dated as of
                            April 1, 1997 between the Company and U.S. Trust Company
                            of Texas, N.A., as Trustee (filed as Exhibit 4.1 to the
                            Company's Quarterly Report on Form 10-Q for the quarter
                            ended March 31, 1997 and incorporated herein by
                            reference).
           4.3           -- First Indenture Supplement relating to $250 million of
                            the Company's 8% Senior Notes Due 2027 dated as of April
                            1, 1997 between the Registrant and U.S. Trust Company of
                            Texas, N.A., as Trustee (filed as Exhibit 4.2 to the
                            Company's Quarterly Report on Form 10-Q for the quarter
                            ended March 31, 1997 and incorporated herein by
                            reference).
           4.4           -- Second Indenture Supplement, between the Company and U.S.
                            Trust Company of Texas, N.A. as Trustee, relating to $100
                            million of the Company's 7 1/4% Senior Debentures Due
                            2097 dated as of August 1, 1997 (filed as Exhibit 4.1 to
                            the Company's Quarterly Report on Form 10-Q for the
                            quarter ended June 30, 1997 and incorporated herein by
                            reference).
           4.5           -- Rights Agreement, dated as of August 27, 1997, between
                            the Company and Liberty Bank and Trust Company of
                            Oklahoma City, N.A., as Rights Agent (filed as Exhibit
                            4.1 to the Company's Registration Statement on Form 8-A
                            filed on August 28, 1997 and incorporated herein by
                            reference).
           4.6           -- Amendment No. 1 to Rights Agreement dated as of December
                            8, 1998, between the Company and Bank One Trust Company,
                            as successor Rights Agent to Liberty Bank and Trust
                            Company of Oklahoma City, N.A. (filed as Exhibit 4.2 to
                            the Company's Registration Statement on Form 8-A/A
                            (Amendment No. 1) filed on December 14, 1998 and
                            incorporated herein by reference.)
           4.7           -- Form of Subordinated Indenture to be entered into
                            relating to the subordinated debt securities (filed as
                            Exhibit 4.2 to the Company's Registration Statement on
                            Form S-3 (Registration No. 333-18929) and incorporated
                            herein by reference).
           5.1           -- Opinion of Thompson & Knight, P.C.
          12.1           -- Computations of Ratio of Earnings to Fixed Charges
          23.1           -- Consent of Arthur Andersen LLP.
          23.2           -- Consent of Thompson & Knight, P.C. (included in Exhibit
                            5.1).
          25.1           -- Form T-1 Statement of Eligibility and Qualification under
                            the Trust Indenture Act of 1939 of U.S. Trust Company of
                            Texas, N.A..
</TABLE>

 
                                      II-2

<PAGE>   28
 
ITEM 17. UNDERTAKINGS.
 
     The undersigned registrant does hereby undertake:
 
          (1) To file, during any period in which offers or sales are being
     made, a post-effective amendment to this Registration Statement:
 
             (i) To include any prospectus required by section 10(a)(3) of the
        Securities Act of 1933;
 
             (ii) To reflect in the prospectus any facts or events arising after
        the effective date of the Registration Statement (or the most recent
        post-effective amendment thereof) which, individually or in the
        aggregate, represent a fundamental change in the information set forth
        in the Registration Statement. Not withstanding the foregoing, any
        increase or decrease in volume of securities offered (if the total
        dollar value of securities offered would not exceed that which has been
        registered) and any deviation from the low or high end of the estimated
        maximum offering range may be reflected in the form of prospectus filed
        with the Commission pursuant to Rule 424(b) if, in the aggregate, the
        changes in volume and price represent no more than a 20% change in the
        maximum aggregate offering price set forth in the "Calculation of
        Registration Fee" table in the effective Registration Statement;
 
             (iii) To include any material information with respect to the plan
        of distribution not previously disclosed in the Registration Statement
        or any material change to the information in the Registration Statement;
 
        provided, however, that paragraphs (i) and (ii) above do not apply if
        the information required to be included in a post-effective amendment by
        those paragraphs is contained in periodic reports filed by the
        registrant pursuant to section 13 or section 15(d) of the Securities
        Exchange Act of 1934 that are incorporated by reference in the
        Registration Statement.
 
          (2) That, for the purpose of determining any liability under the
     Securities Act of 1933, each post-effective amendment shall be deemed to be
     a new Registration Statement relating to the securities offered therein and
     the offering of such securities at that time shall be deemed to be the
     initial bona fide offering thereof.
 
          (3) To remove from registration by means of a post-effective amendment
     any of the securities being registered that remain unsold at the
     termination of the offering.
 
     The undersigned registrant hereby undertakes that, for purposes of
     determining any liability under the Securities Act of 1933, each filing of
     the registrant's Annual Report on Form 10-K pursuant to section 13(a) or
     section 15(d) of the Securities Exchange Act of 1934 (and, where
     applicable, each filing of an employee benefit plan's annual report
     pursuant to section 15(d) of the Securities Exchange Act of 1934) that is
     incorporated by reference in the Registration Statement shall be deemed to
     be a new Registration Statement relating to the securities offered therein,
     and the offering of securities at that time shall be deemed to be the
     initial bona fide offering thereof.
 
     Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to our directors, officers and controlling persons
pursuant to the provisions described in Item 15 above, or otherwise, we have
been advised that in the opinion of the Securities and Exchange Commission,
indemnification of this type is against public policy as expressed in the Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against those liabilities (other than the payment by us of expenses incurred or
paid by a director, officer or controlling person in the successful defense of
any action, suit or proceeding) is asserted by the director, officer or
controlling person in connection with the securities being registered, we will,
unless, in the opinion of our counsel, the matter has been settled by
controlling precedent, submit to a court of appropriate jurisdiction the
question whether the indemnification by it is against public policy as expressed
in the Act and will be governed by the final adjudication of the issue.
 
                                      II-3

<PAGE>   29
 

                                   SIGNATURES
 
     Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-3 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, hereunto duly
authorized, in the City of Ardmore, State of Oklahoma, on the 15th day of July,
1999.
 
                                            NOBLE AFFILIATES, INC.
 
                                            By:      /s/ ROBERT KELLEY
                                              ----------------------------------
                                                        Robert Kelley
                                               Chairman of the Board, President
                                                              and
                                                   Chief Executive Officer
 
     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons in the
capacities and on the dates indicated.
 

<TABLE>
<CAPTION>
                      SIGNATURE                                      TITLE                        DATE
                      ---------                                      -----                        ----
<C>                                                    <S>                                 <C>
 
                  /s/ ROBERT KELLEY                    Chairman of the Board, President,     July 15, 1999
-----------------------------------------------------    Chief Executive Officer and
                    Robert Kelley                        Director (Principal Executive
                                                         Officer)
 
                /s/ JAMES L. MCELVANY                  Vice President -- Finance and         July 15, 1999
-----------------------------------------------------    Treasurer (Principal Financial
                  James L. McElvany                      and Principal Accounting
                                                         Officer)
 
                  /s/ ALAN A. BAKER                    Director                              July 15, 1999
-----------------------------------------------------
                    Alan A. Baker
 
                /s/ MICHAEL A. CAWLEY                  Director                              July 15, 1999
-----------------------------------------------------
                  Michael A. Cawley
 
                  /s/ EDWARD F. COX                    Director                              July 15, 1999
-----------------------------------------------------
                    Edward F. Cox
 
                  /s/ JAMES C. DAY                     Director                              July 15, 1999
-----------------------------------------------------
                    James C. Day
 
                /s/ THOMAS E. HASSEN                   Director                              July 15, 1999
-----------------------------------------------------
                  Thomas E. Hassen
 
                  /s/ DALE P. JONES                    Director                              July 15, 1999
-----------------------------------------------------
                    Dale P. Jones
 
               /s/ HAROLD F. KLEINMAN                  Director                              July 15, 1999
-----------------------------------------------------
                 Harold F. Kleinman
 
                  /s/ T. DON STACY                     Director                              July 15, 1999
-----------------------------------------------------
                    T. Don Stacy
</TABLE>

 
                                      II-4

<PAGE>   30
 

                               INDEX TO EXHIBITS
 

<TABLE>
<CAPTION>
        EXHIBIT
         NUMBER                                    EXHIBIT
        -------                                    -------
<C>                      <S>
          4.1            -- Indenture dated as of October 14, 1993 between the
                            Company and U.S. Trust Company of Texas, N.A., as
                            Trustee, relating to the Company's 7 1/4% Notes Due 2023,
                            including form of the Company's 7 1/4% Notes Due 2023
                            (filed as Exhibit 4.1 to the Company's Quarterly Report
                            on Form 10-Q for the quarter ended September 30, 1993 and
                            incorporated herein by reference).
          4.2            -- Indenture relating to senior debt securities dated as of
                            April 1, 1997 between the Company and U.S. Trust Company
                            of Texas, N.A., as Trustee (filed as Exhibit 4.1 to the
                            Company's Quarterly Report on Form 10-Q for the quarter
                            ended March 31, 1997 and incorporated herein by
                            reference).
          4.3            -- First Indenture Supplement relating to $250 million of
                            the Company's 8% Senior Notes Due 2027 dated as of April
                            1, 1997 between the Registrant and U.S. Trust Company of
                            Texas, N.A., as Trustee (filed as Exhibit 4.2 to the
                            Company's Quarterly Report on Form 10-Q for the quarter
                            ended March 31, 1997 and incorporated herein by
                            reference).
          4.4            -- Second Indenture Supplement, between the Company and U.S.
                            Trust Company of Texas, N.A. as Trustee, relating to $100
                            million of the Company's 7 1/4% Senior Debentures Due
                            2097 dated as of August 1, 1997 (filed as Exhibit 4.1 to
                            the Company's Quarterly Report on Form 10-Q for the
                            quarter ended June 30, 1997 and incorporated herein by
                            reference).
          4.5            -- Rights Agreement, dated as of August 27, 1997, between
                            the Company and Liberty Bank and Trust Company of
                            Oklahoma City, N.A., as Right Agent (filed as Exhibit 4.1
                            to the Company's Registration Statement on Form 8-A filed
                            on August 28, 1997 and incorporated herein by reference).
          4.6            -- Amendment No. 1 to Rights Agreement dated as of December
                            8, 1998, between the Company and Bank One Trust Company,
                            as successor Rights Agent to Liberty Bank and Trust
                            Company of Oklahoma City, N.A. (filed as Exhibit 4.2 to
                            the Company's Registration Statement on Form 8-A/A
                            (Amendment No. 1) filed on December 14, 1998 and
                            incorporated herein by reference.)
          4.7            -- Form of Subordinated Indenture to be entered into
                            relating to the subordinated debt securities (filed as
                            Exhibit 4.2 to the Company's Registration Statement on
                            Form S-3 (Registration No. 333-18929) and incorporated
                            herein by reference).
          5.1            -- Opinion of Thompson & Knight, P.C.
         12.1            -- Computations of Ratio of Earnings to Fixed Charges
         23.1            -- Consent of Arthur Andersen LLP.
         23.2            -- Consent of Thompson & Knight, P.C. (included in Exhibit
                            5.1).
         25.1            -- Form T-1 Statement of Eligibility and Qualification under
                            the Trust Indenture Act of 1939 of U.S. Trust Company of
                            Texas, N.A..
</TABLE>






<PAGE>   1
                                                                     Exhibit 5.1

                                 July 15, 1999

Noble Affiliates, Inc.
110 W. Broadway
Ardmore, Oklahoma  73401

         Re: Noble Affiliates, Inc. Registration Statement on Form S-3

Ladies and Gentlemen:

         We have acted as counsel to Noble Affiliates, Inc., a Delaware
corporation (the "Company"), in connection with the preparation and filing of
the Company's Registration Statement on Form S-3 (the "Registration Statement")
to be filed with the Securities and Exchange Commission (the "Commission") on
July 15, 1999 under the Securities Act of 1933, as amended (the "Securities
Act"). The Registration Statement relates to the issuance and sale from time to
time, pursuant to the General Rules and Regulations promulgated under the
Securities Act of $800,000,000 aggregate gross proceeds of (i) debt securities,
which may be either senior (the "Senior Debt Securities") or subordinated (the
"Subordinated Debt Securities" and, together with the Senior Debt Securities,
the "Debt Securities"), (ii) shares of common stock, par value $3.33- 1/3 per
share, of the Company (the "Common Stock"), (iii) shares of preferred stock, par
value $1.00 per share, of the Company (the "Preferred Stock"), (iv) warrants to
purchase Debt Securities (the "Debt Warrants"), shares of Common Stock (the
"Common Stock Warrants")
 and shares of Preferred Stock (the "Preferred Stock
Warrants" and, together with the Debt Warrants and the Common Stock Warrants,
the "Securities Warrants") of the Company, (v) Debt Securities, Common Stock and
Preferred Stock that may be issued upon exercise of the Securities Warrants and
(vi) such indeterminate amount of Offered Securities (as defined below) as may
be issued in exchange for or upon conversion of, as the case may be, the Offered
Securities. Pursuant to Rule 429 of the Securities Act, the prospectus included
in the Registration Statement (the "Prospectus") will also be used in connection
with registration statement No. 333-18929 filed on December 27, 1996 by the
Company on Form S-3, pursuant to which $225,000,000 aggregate proceeds of
securities remain unsold and are included in the Prospectus in addition to the
$800,000,000 aggregate proceeds of securities covered by the Registration
Statement. The Debt Securities, Common Stock, Preferred Stock and Securities
Warrants are hereinafter referred to collectively as the "Offered Securities."

         The Offered Securities will be sold or delivered from time to time as
set forth in the Registration Statement, any amendment thereto, the Prospectus
and supplements to the Prospectus (the "Prospectus Supplements"). The Senior
Debt Securities will be issued under the Indenture dated as of April 1, 1997
between the Company and U.S. Trust Company of Texas, N.A., as Trustee (as
amended and supplemented, the "Senior Indenture"). Any Subordinated Debt
Securities will be issued under an Indenture to be entered into between the
Company and a trustee to be appointed (the "Subordinated Indenture"). The forms
of the Senior Indenture and Subordinated Indenture (collectively, the
"Indentures") are included (by incorporation by reference) as exhibits to the
Registration Statement.

         This opinion is delivered in accordance with the requirements of Item
601(b)(5) of Regulation S-K under the Securities Act.


<PAGE>   2

Noble Affiliates, Inc.
July 15, 1999
Page 2


         In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of the Registration
Statement and such agreements, certificates of public officials, certificates of
trustees, certificates of officers or other representatives of the Company and
others, and such other documents, certificates and records as we have deemed
necessary or appropriate as a basis for the opinions set forth herein.

         In our examination, we have assumed the legal capacity of all natural
persons, the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity to original documents of all
documents submitted to us as certified, conformed or photostatic copies and the
authenticity of the originals of such latter documents. In making our
examination of executed documents and documents to be executed, we have assumed
that the parties thereto had or will have the power, corporate, trust or other,
to enter into and perform all obligations thereunder and have also assumed the
due authorization by all requisite action, corporate or other, and execution and
delivery by such parties of such documents and the validity and binding effect
thereof on such parties. As to any facts material to the opinions expressed
herein that were not independently established or verified, we have relied upon
oral or written statements and representations of officers and other
representatives of the Company, trustees and others.

         Based upon the foregoing, and subject to the qualifications and
limitations set forth herein, we are of the opinion that:

         1. The Debt Securities have been duly authorized by the Company and,
         (i) when the Registration Statement has become effective under the
         Securities Act, (ii) in the case of Subordinated Debt Securities, when
         the Subordinated Indenture has been duly executed and delivered by the
         parties thereto and (iii) when the Debt Securities have been duly
         executed and authenticated in accordance with the terms of the
         Indentures and delivered and sold upon payment in full therefor as
         contemplated by the Registration Statement, such Debt Securities will
         constitute valid and legally binding obligations of the Company
         enforceable in accordance with their terms and entitled to the benefits
         of such Indentures.

         2. The shares of Common Stock being registered under the Registration
         Statement have been duly authorized by the Company and (i) when the
         Registration Statement has become effective under the Securities Act
         and (ii) when the shares of Common Stock have been delivered by the
         Company upon purchase thereof and payment in full therefor as
         contemplated by the Registration Statement, such shares of Common Stock
         will be validly issued, fully paid and nonassessable.

         3. The shares of Preferred Stock being registered under the
         Registration Statement will be duly authorized by the Company, validly
         issued, fully paid and nonassessable when (i) the Registration
         Statement has become effective under the Act, (ii) a certificate of
         designations relating to the series of the Preferred Stock being
         issued, in a form to be included as an exhibit of the Registration
         Statement, has been duly approved and adopted and filed with the
         Secretary of State of Delaware and (iii) the shares of Preferred Stock
         have been delivered by the Company upon purchase thereof and payment in
         full therefor as contemplated by the Registration Statement.

         4. The Securities Warrants have been duly authorized by the Company and
         (i) when the Registration Statement has become effective under the Act,
         (ii) upon the execution and delivery of a debt warrant agreement,
         common stock warrant agreement or preferred stock warrant agreement,


<PAGE>   3

Noble Affiliates, Inc.
July 15, 1999
Page 3


         as the case may be, relating to such Securities Warrants in a form to
         be included as an exhibit to the Registration Statement, and (iii)
         when such Securities Warrants have been duly executed, countersigned,
         delivered and sold in the applicable form and as contemplated by the
         Registration Statement, such Securities Warrants will constitute valid
         and legally binding obligations of the Company enforceable against the
         Company in accordance with their terms.

         The opinions expressed above are limited by and subject to the
following qualifications:

         (a) We express no opinion other than as to the federal securities laws
of the United States of America, the laws of the State of New York and the
General Corporation Law of the State of Delaware; provided, however, we have
assumed, without investigation, that the laws of the State of New York are
identical in all respects to the laws of the State of Texas.

         (b) In rendering the opinions expressed herein, we have assumed that no
action heretofore taken by the Board of Directors of the Company in connection
with the matters described or referred to herein will be modified, rescinded or
withdrawn after the date hereof.

         (c) The opinions expressed in paragraphs 1 and 4 above are subject to
the qualification that the validity and binding effect of the Offered Securities
and the Indentures may be limited or affected by (i) bankruptcy, insolvency,
reorganization, fraudulent transfer or conveyance, receivership, moratorium and
other similar laws relating to or affecting creditors' rights generally, (ii)
general principles of equity, regardless of whether applied in a proceeding in
equity or at law, and (iii) an implied covenant of good faith and fair dealing.

         We hereby consent to the filing of this opinion with the Commission as
Exhibit 5.1 to the Registration Statement. We also consent to the reference to
our firm under the caption "Legal Matters" in the Registration Statement. In
giving this consent, we do not thereby admit that we are in the category of
persons whose consent is required under Section 7 of the Securities Act or the
Rules and Regulations of the Commission promulgated thereunder. This opinion is
expressed as of the date hereof unless otherwise expressly stated, and we
disclaim any undertaking to advise you of any subsequent changes of the facts
stated or assumed herein or any subsequent changes in applicable law.

                                            Respectfully submitted,

                                            THOMPSON & KNIGHT, P.C.


                                            By: /s/ KENN W. WEBB
                                                --------------------------------
                                                Kenn W. Webb, Attorney




<PAGE>   1
                                                                    EXHIBIT 12.1


                             NOBLE AFFILIATES, INC
               COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES
                                 (in thousands)



<TABLE>
<CAPTION>
                                          1994           1995           1996           1997          1998         1st Qtr 99
                                         -------        -------        -------        -------      ---------      ----------
<S>                                      <C>            <C>            <C>            <C>          <C>            <C>
Income (loss) before taxes                 5,225          7,998        136,289        157,685       (246,708)       (12,035)
Add (deduct)
   Fixed charges                          24,782         21,915         38,547         53,066         50,597         13,040
   Interest capitalized                   (7,183)        (3,127)        (2,165)        (6,239)        (6,753)        (1,123)
                                         -------        -------        -------        -------      ---------        -------
Earnings as defined                       22,824         26,786        172,671        204,512       (202,864)          (118)
                                         =======        =======        =======        =======      =========        =======

Net interest expense                      17,546         18,744         36,309         46,769         43,758         11,912
Interest capitalized                       7,183          3,127          2,165          6,239          6,753          1,123
Interest portion of rental expense            53             44             73             58             86              5
                                         -------        -------        -------        -------      ---------        -------
Fixed charges as defined                  24,782         21,915         38,547         53,066         50,597         13,040
                                         =======        =======        =======        =======      =========        =======

Ratio of earnings to fixed charges        0.9210         1.2223         4.4795         3.8539        -4.0094        -0.0090


Rental expense admin report              911,407        846,342        826,649        802,262      1,207,026        312,959

Weighted average rate                      0.058          0.052          0.088          0.072          0.071         0.0173

Interest portion of rent expense          52,862         44,010         72,745         57,763         85,699          5,414
</TABLE>






<PAGE>   1
                                                                    EXHIBIT 23.1

             CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS




As independent public accountants, we hereby consent to the incorporation by
reference in this registration statement of our report dated January 29, 1999,
included in the Company's Form 10-K, as amended, for the year ended December
31, 1998, and to all references to our Firm included in this registration
statement.


                               ARTHUR ANDERSEN LLP


Oklahoma City, Oklahoma,
July 12, 1999








<PAGE>   1
                                                                   EXHIBIT 25.1

===============================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                ---------------

                                    FORM T-1

           STATEMENT OF ELIGIBILITY AND QUALIFICATION UNDER THE TRUST
      INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE

             CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A
                     TRUSTEE PURSUANT TO SECTION 305(b)(2)

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

                       U.S. TRUST COMPANY OF TEXAS, N.A.
              (Exact name of trustee as specified in its charter)

                                                               75-2353745
(State of incorporation                                     (I.R.S. employer
 if not a national bank)                                   identification no.)

 2001 Ross Avenue, Suite 2700                                   75201-2936
      Dallas, Texas                                             (Zip code)
  (Address of trustee's
principal executive offices)

                               Compliance Officer
                       U.S. Trust Company of Texas, N.A.
                          2001 Ross Avenue, Suite 2700
                            Dallas, Texas 75201-2936
                                 (214) 754-1200
           (Name, address and telephone number of agent for service)

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

                             Noble Affiliates, Inc.
              (Exact name of obligor as specified in its charter)

         Delaware                                              73-0785597
(State or other jurisdiction of                             (I.R.S. employer
 incorporation or organization)                            identification no.)

          110 West Broadway
          Ardmore, Oklahoma                                        73401
(Address of principal executive offices)                         (Zip code)

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


                             Senior Debt Securities

===============================================================================

<PAGE>   2

                                    GENERAL

1.  General Information.

    Furnish the following information as to the Trustee:

    (a)  Name and address of each examining or supervising authority to
 which 
         it is subject.

                Federal Reserve Bank of Dallas (11th District), Dallas, Texas
                   (Board of Governors of the Federal Reserve System)
                Federal Deposit Insurance Corporation, Dallas, Texas
                The Office of the Comptroller of the Currency, Dallas, Texas

    (b)  Whether it is authorized to exercise corporate trust powers.

                The Trustee is authorized to exercise corporate trust powers.

2.  Affiliations with Obligor and Underwriters.

    If the obligor or any underwriter for the obligor is an affiliate of
    the Trustee, describe each such affiliation.

    None.

3.  Voting Securities of the Trustee.

    Furnish the following information as to each class of voting securities of 
    the Trustee:

As of July 6, 1999


<TABLE>
<S>                                                     <C>
-------------------------------------------------------------------------------

          Col A.                                              Col B.
-------------------------------------------------------------------------------

      Title of Class                                    Amount Outstanding
-------------------------------------------------------------------------------

Capital Stock - par value $100 per share                  5,000 shares
</TABLE>


4.  Trusteeships under Other Indentures.

    7.25% Notes due October 15, 2023 
    8.0% Senior Notes due 2027 
    7.25% senior Debentures due 2097

5.  Interlocking Directorates and Similar Relationships with the Obligor or
    Underwriters.

    Not Applicable



<PAGE>   3

6.  Voting Securities of the Trustee Owned by the Obligor or its Officials.

    Not Applicable

7.  Voting Securities of the Trustee Owned by Underwriters or their Officials.

    Not Applicable

8.  Securities of the Obligor Owned or Held by the Trustee.

    Not Applicable

9.  Securities of Underwriters Owned or Held by the Trustee.

    Not Applicable

10. Ownership or Holdings by the Trustee of Voting Securities of Certain
    Affiliates or Security Holders of the Obligor.

    Not Applicable

11. Ownership or Holdings by the Trustee of any Securities of a Person
    Owning 50 Percent or More of the Voting Securities of the Obligor.

    Not Applicable

12. Indebtedness of the Obligor to the Trustee.

    Not Applicable

13. Defaults by the Obligor.

    Not Applicable

14. Affiliations with the Underwriters.

    Not Applicable

15. Foreign Trustee.

    Not Applicable

16. List of Exhibits.

    T-1.1  -   A copy of the Articles of Association of U.S. Trust Company of
               Texas, N.A.; incorporated herein by reference to Exhibit T-1.1
               filed with Form T-1 Statement, Registration No. 22-21897.



<PAGE>   4

16. (con't.)

    T-1.2  -   A copy of the certificate of authority of U.S. Trust Company of
               Texas, N.A. to commence business; incorporated herein by
               reference to Exhibit T-1.2 filed with Form T-1 Statement,
               Registration No. 22-21897.

    T-1.3  -   A copy of the authorization of U.S. Trust Company of Texas, N.A.
               to exercise corporate trust powers; incorporated herein by
               reference to Exhibit T-1.3 filed with Form T-1 Statement,
               Registration No. 22-21897.

    T-1.4  -   A copy of the By-laws of the U.S. Trust Company of Texas, N.A.,
               as amended to date; incorporated herein by reference to Exhibit
               T-1.4 filed with Form T-1 Statement, Registration No. 22-21897.

    T-1.6  -   The consent of the Trustee required by Section 321(b) of the
               Trust Indenture Act of 1939.

    T-1.7  -   A copy of the latest report of condition of the Trustee
               published pursuant to law or the requirements of its supervising
               or examining authority.


                                      NOTE

As of July 6, 1999, the Trustee had 5,000 shares of Capital Stock outstanding,
all of which are owned by U.S. T.L.P.O. Corp. As of July 6, 1999, U.S. T.L.P.O.
Corp. had 35 shares of Capital Stock outstanding, all of which are owned by
U.S. Trust Corporation. U.S. Trust Corporation had outstanding 18,433,136.00
shares of $1 par value Common Stock as of July 6, 1999.

The term "Trustee" in Items 2, 5, 6, 7, 8, 9, 10 and 11 refers to each of U.S
Trust Company of Texas, N.A., U.S. T.L.P.O. Corp. and U.S. Trust Corporation.

Inasmuch as this Form T-1 is filed prior to the ascertainment by the Trustee of
all the facts on which to base responsive answers to Items 2, 5, 6, 7, 9, 10
and 11, the answers to said Items are based upon incomplete information. Items
2, 5, 6, 7, 9, 10 and 11 may, however, be considered correct unless amended by
an amendment to this Form T-1.

In answering any items in this Statement of Eligibility and Qualification which
relates to matters peculiarly within the knowledge of the obligors or their
directors or officers, or an underwriter for the obligors, the Trustee has
relied upon information furnished to it by the obligors and will rely on
information to be furnished by the obligors or such underwriter, and the
Trustee disclaims responsibility for the accuracy or completeness of such
information.


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


<PAGE>   5

SIGNATURE

Pursuant to the requirements of the Trust Indenture Act of 1939 the Trustee,
U.S Trust Company of Texas, N.A., a national banking association organized and
existing under the laws of the United States of America, has duly caused this
statement of eligibility and qualification to be signed on its behalf by the
undersigned, thereunto duly authorized, all in the City of Dallas, and State of
Texas on the 6th day of July, 1999.

                                        U.S. Trust Company of Texas, N.A.,
                                        Trustee



                                        By:  /s/ BILL BARBER
                                            -------------------------------
                                                  Bill Barber
                                                  Vice President


<PAGE>   6

                                                                  Exhibit T-1.6



CONSENT OF TRUSTEE

Pursuant to the requirements of Section 321(b) of the Trust Indenture Act of
1939 as amended in connection with the proposed issue of Noble Affiliates, Inc.
Senior Debt Securities, we hereby consent that reports of examination by
Federal, State, Territorial or District authorities may be furnished by such
authorities to the Securities and Exchange Commission upon request therefore.

                                        U.S. Trust Company of Texas, N.A.,
                                        Trustee



                                        By: /s/ BILL BARBER
                                            -------------------------------
                                                  Bill Barber
                                                  Vice President



<PAGE>   7

<TABLE>
<S>                                                                   <C>               <C>
                                                                                        OMB NUMBER:  7100-003                     
                                                                                        FEDERAL DEPOSIT INSURANCE CORPORATION     
                                                                                        OMB NUMBER:  3064-005                     
                                                                                        OFFICE OF THE COMPTROLLER OF THE CURRENCY 
                                                                                        EXPIRES MARCH 31, 2001                    
                                                                                        
FEDERAL FINANCIAL INSTITUTIONS EXAMINATION COUNCIL
----------------------------------------------------------------------------------------------------------------------------------
                                                                                                                         -----   
                                                                                                                           1     
                                                                                                                         -----

                                                                                        PLEASE REFER TO PAGE 1,   
                                                                                        TABLE OF CONTENTS, FOR    
                                                                                        THE REQUIRED DISCLOSURE   
                                                                                        OF ESTIMATED BURDEN.      
----------------------------------------------------------------------------------------------------------------------------------

CONSOLIDATED REPORTS OF CONDITION AND INCOME FOR 
A BANK WITH DOMESTIC OFFICES ONLY AND TOTAL ASSETS OF 
$100 MILLION OR MORE BUT LESS THAN $300 MILLION - FFIEC 033

REPORT AT THE CLOSE OF BUSINESS                                                            19990331
                                                                                           --------
                                                                                          (RCRI 9999)

This report is required by law:  12 U.S.C. Section 324 (State          This report form is to be filed by banks with domestic 
member banks); 12 U.S.C. Section 1817 (State nonmember banks);         offices only.  Banks with foreign offices (as defined in
and 12 U.S.C. Section 161 (National banks).                            the instructions) must file FFIEC 031.
----------------------------------------------------------------------------------------------------------------------------------

NOTE:  The Reports of Condition and Income must be signed              The Reports of Condition and Income are to be prepared in
by an authorized officer and the Report of Condition must be           Accordance with Federal regulatory authority instructions.
attested to by not less than two directors (trustees) for State        nonmember banks
and three directors for State member and national Banks.


                                                                       We, the undersigned directors (trustees), attest to the
                                                                       correctness of the Report of Condition (including the
I, Alfred B. Childs, Managing Director                                 supporting schedules) for this report date and declare that
-------------------------------------------------------------------    it has been examined by us and to the best of our knowledge
Name and Title of Officer Authorized to Sign Report                    and belief has been prepared in conformance with the
                                                                       instructions issued by the appropriate Federal regulatory
Of the named bank do hereby declare that the Reports of Condition and  authority and is trust and correct.
Income (including the supporting schedules) for this report date have
been prepared in conformance with the instructions issued y the
appropriate Federal regulatory authority and are true to the best
of my knowledge.                                                       /s/ Stuart M. Pearman
                                                                       -----------------------------------------------------------
                                                                       Director (Trustee)

/s/ Alfred B. Childs                                                   /s/ J. T. More, Jr.
-------------------------------------------------------------------    -----------------------------------------------------------
Signature of Officer Authorized to Sign Report                         Director (Trustee)

April 21, 1999                                                         /s/ Arthur White
-------------------------------------------------------------------    -----------------------------------------------------------
Date of Signature                                                      Director (Trustee)

----------------------------------------------------------------------------------------------------------------------------------
SUBMISSION OF REPORTS

Each bank must prepare its Reports of Condition and Income             (if other than EDS) must transmit the bank's computer
either:                                                                data file to EDS.

(a)   in electronic form and then file the computer data file          For electronic filing assistance, contact EDS Call Report
      directly with the banking agencies' collection agent,            Services, 2150 N. Prospect Ave., Milwaukee, WI 53202,
      Electronic Data Systems Corporation (EDS), by modem or on        telephone (800) 255-1571.
      computer diskette; or
                                                                       To fulfill the signature and attestation requirement for the
(b)   in hard-copy (paper) form and arrange for another party to       Reports of Condition and Income for this report date, attach
      convert the paper report to electronic form. That party          this signature page (or a photocopy or a computer-generated
                                                                       version of this page) to the hard-copy record of the
                                                                       completed report that the bank places in its files.

----------------------------------------------------------------------------------------------------------------------------------
FDIC Certificate Number:           33217                               U.S. TRUST COMPANY OF TEXAS, N.A.
                                   -----                               -----------------------------------------------------------
                                (RCRI 9050)                            Legal Title of Bank (TEXT 9010)

                                                                       DALLAS
                                                                       -----------------------------------------------------------
                                                                       City (TEXT 9130)

                                                                       TX                                     75201
                                                                       -----------------------------------------------------------
                                                                       State Abbrev. (TEXT 9200)              Zip Code (TEXT 9220)


Board of Governors of the Federal Reserve System, Federal Deposit Insurance Corporation, Office of the Comptroller of the Currency
</TABLE>




<PAGE>   8


<TABLE>
<S>                                        <C>                                        <C>                                <C>
U.S. TRUST COMPANY OF TEXAS, N.A.           Call Date: 3/31/99                          State #: 48-6797                 FFIEC 033
2001 ROSS AVENUE, SUITE 2700                Vendor ID: D                                Cert #: 33217                      RC-1
DALLAS, TX  75201                           Transit #: 11101765
                                                                                                                           -----
                                                                                                                             9
                                                                                                                           -----

CONSOLIDATED REPORT OF CONDITION FOR INSURED COMMERCIAL
AND STATE-CHARTERED SAVINGS BANKS FOR

All Schedules are to be reported in thousands of dollars. Unless otherwise
indicated, report the amount outstanding as of the last business day of the
quarter.

SCHEDULE RC - BALANCE SHEET
                                                                                                                              C200
                                                                                                 Dollar Amounts In Thousands
----------------------------------------------------------------------------------------------------------------------------------
ASSETS

  1.  Cash and balances due from depository institutions (from Schedule RC-A):                            RCON
                                                                                                          ----
    a.  Noninterest-bearing balances and currency and coin (1)                                            0081         1,297  1.a
                                                               ------------------------------------------         -----------
    b.  Interest-bearing balances (2)                                                                     0071           696  1.b
                                       ------------------------------------------------------------------         -----------
  2.  Securities:

    a.  Held-to-maturity securities (from Schedule RC-B, Column A)                                        1754             0  2.a
                                                                    -------------------------------------         -----------
    b.  Available-for-sale securities (from Schedule RC-B, column D)                                      1773       131,683  2.b
                                                                      -----------------------------------         -----------
  3.  Federal funds sold and securities purchased under agreements to resell                              1350         6,000  3.
                                                                             ----------------------------         -----------
  4.  Loans and lease financing receivables:                                         RCO
                                                                                     ---
                                                                                     N
                                                                                     --
    a.  Loans and leases, net of unearned income (from Schedule RC-C)                2122         22,709                      4.a
                                                                           ---------         ------------
    b.  LESS:  Allowance for loan and lease losses                                   3123            260                      4.b
                                                   ---------------------------------         ------------
    c.  LESS:  Allocated transfer risk reserve                                       3128              0                      4.c
                                               -------------------------------------         ------------
    d.  Loans and leases, net of unearned income, allowance, and reserve (item 4.a                        RCO
                                                                                                          ---
                                                                                                          N
                                                                                                          --
         minus 4.b and 4.c)                                                                               2125        22,249  4.d
                             ----------------------------------------------------------------------------         -----------
  5.  Trading assets                                                                                      3545             0  5.
                     ------------------------------------------------------------------------------------         -----------
  6.  Premises and fixed assets (including capitalized leases)                                            2145           917  6.
                                                               ------------------------------------------         -----------
  7.  Other real estate owned (from Schedule RC-M)                                                        2150             0  7.
                                                   ------------------------------------------------------         -----------
  8.  Investments in unconsolidated subsidiaries and associated companies (from Schedule RC-M)            2130             0  8.
                                                                                               ----------         -----------
  9.  Customers' liability to this bank on acceptances outstanding                                        2155             0  9.
                                                                    -------------------------------------         -----------
 10.  Intangible assets (from Schedule RC-M)                                                              2143         1,950  10.
                                            -------------------------------------------------------------         -----------
 11.  Other assets (from Schedule RC-F)                                                                   2160         2,527  11.
                                       ------------------------------------------------------------------         -----------
 12.  Total assets (sum of items 1 through 11)                                                            2170       167,519  12.
                                              -----------------------------------------------------------         -----------
</TABLE>


(1)      Includes cash items in process of collection and unposted debits.
(2)      Includes time certificates of deposit not held for trading.


<PAGE>   9



<TABLE>
<S>                                        <C>                                        <C>                                <C>
U.S. TRUST COMPANY OF TEXAS, N.A.           Call Date: 3/31/99                         State #: 48-6797                  FFIEC 033
2001 ROSS AVENUE, SUITE 2700                Vendor ID: D                                Cert #: 33217                      RC-1
DALLAS, TX  75201                           Transit #: 11101765
                                                                                                                           -----
                                                                                                                            10
                                                                                                                           -----

SCHEDULE RC - CONTINUED
                                                                                                 Dollar Amounts In Thousands
-----------------------------------------------------------------------------------------------------------------------------------
LIABILITIES

13.  Deposits:                                                                                             RCON
                                                                                                           ----
     a.  In domestic offices (sum of totals of columns A and C From Schedule RC-E)   RCON                  2200     141,618  13.a
                                                                                     ----                         --------- 
         (1) Noninterest-bearing (1)                                                 6631           8,794                    13.a.1
                                     -----------------------------------------------          ------------
         (2) Interest-bearing                                                        6636         132,824                    13.a.2
                                 ---------- --------- --------- ---------- ---------          ------------
     b.  In foreign offices, Edge and Agreement subsidiaries, and IBFs 

         (1) Noninterest-bearing
                                  --------------------------------------------------
         (2) Interest-bearing                                                                              RCON
                              ------------------------------------------------------                       ----
14.  Federal funds purchased and securities sold under agreements to repurchase                            2800           0  14
                                                                                --------------------------        ---------- 
15.  a.  Demand notes issued to the U.S. Treasury                                                          2840           0  15.a
                                                  --------------------------------------------------------        ---------- 
     b.  Trading liabilities                                                                               3548           0  15.b
                             -----------------------------------------------------------------------------        ---------- 

16. Other borrowed money (includes mortgage indebtedness and obligations under capitalized leases):

     a.  With a remaining maturity of one year or less                                                     2332           0  16.a
                                                       -----------------------------                              ---------- 
     b.  With a remaining maturity of more than one year through three years                               A547       2,000  16.b
                                                                              ----------------------------        ---------- 
     c.  With a remaining maturity of more than three years                                                A548       1,000  16.c
                                                            ----------------------------------------------        ---------- 
17.  Not applicable

18.  Bank's liability on acceptances executed and outstanding                                              2920           0  18
                                                               -------------------------------------------        ---------- 
19.  Subordinated notes and debentures (2)                                                                 3200           0  19
                                            --------------------------------------------------------------        ---------- 
20.  Other liabilities (from Schedule RC-G)                                                                2930       2,317  20
                                             -------------------------------------------------------------        ---------- 
21.  Total liabilities (sum of items 13 through 20)                                                        2948     146,935  21
                                                    ------------------------------------------------------        ---------- 
22.  Not applicable

EQUITY CAPITAL                                                                                             RCON
                                                                                                           ----
23.  Perpetual preferred stock and related surplus                                                         3838       7,000  23
                                                   -------------------------------------------------------        ---------- 
24.  Common stock                                                                                          3230         500  24
                   ---------------------------------------------------------------------------------------        ---------- 
25.  Surplus (exclude all surplus related to preferred stock)                                              3839       8,384  25
                                                              --------------------------------------------        ---------- 
26.  a.  Undivided profits and capital reserves                                                            3632       4,406  26.a
                                                 ---------------------------------------------------------        ---------- 
     b.  Net unrealized holding gains (losses) on available-for-sale securities                            8434         294  26.b
                                                                                  ------------------------        ---------- 
     c.  ACCUMULATED NET GAINS (LOSSES ON CASH FLOW HEDGES)                                                4336           0  26.c
                                                              --------------------------------------------        ---------- 
27.  Cumulative foreign currency translation adjustments
                                                          ------------------------------------------------
28.  Total equity capital (sum of items 23 through 27)                                                     3210      20,584  28
                                                        ---------------------------------------------------        ---------- 
29.  Total liabilities and equity capital (sum of items 21 and 28)                                         3300     167,519  29
                                                                    --------------------------------------        ---------- 

MEMORANDUM

TO BE REPORTED ONLY WITH THE REPORT OF CONDITION.
1.   Indicate in the at the right, the number of the statement below that best
     describes the most comprehensive level of auditing work performed for the
     bank by independent external auditors as of any date during 1998                                      6724           1  M.1
                                                                      ------------------------------------        ---------- 
</TABLE>



<TABLE>
<S>                                                                 <C>
1 = Independent audit of the bank conducted in accordance            4 = Directors' examination of the bank performed by other
    with generally accepted auditing standards by a                      external auditors (may be required by state chartering
    certified  public accounting firm which submits a report             authority)
    on the bank                                                      5 = Review of the bank's financial statements by external  
2 = Independent audit of the bank's parent holding company                auditors                                              
    conducted in accordance with generally accepted                  6 = Compilation of the bank's financial statements by      
    auditing standards by a certified public accounting                  external auditors                                      
    firm which submits a report on the consolidated holding          7 = Other audit procedures (excluding tax preparation work)
    company (but not on the bank separately)                         8 = No external audit work
3 = Directors' examination of the bank conducted in
    accordance with generally accepted auditing standards
    by a certified public accounting firm (may be required
    by state chartering authority)
</TABLE>


(1)  Includes total demand deposits and noninterest-bearing time and savings 
     deposits.
(2)  Includes limited-life preferred stock and related surplus.