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                                                                   EXHIBIT 10.15

                            SHARE PURCHASE AGREEMENT

Agreement entered into as of this 18th day of October 1996, by and
between (1) Abbot Group plc a public company formed and existing under the laws
of England with registered number 623285 ("Abbot"), (2) Nabors Industries, Inc
a company formed and existing under the laws of the State of Delaware, USA (the
"Seller") and (3) KCA Drilling Group Limited, a company formed and existing
under the laws of England with registered number 1059871 ("the Buyer").  Abbot,
the Seller and the Buyer are referred to collectively herein as the "Parties".

The Seller owns all of the issued shares of Nabors Europe, Ltd., a company
formed and existing under the laws of England with registered number 1189464
(the "Company").

This Agreement contemplates a transaction in which the Buyer will purchase from
the Seller, and the Seller will sell to the Buyer, all of the issued shares of
the Company in return for cash and the issue of warrants to subscribe for
shares in Abbot upon and subject to the terms of this Agreement.

Now, therefore, in consideration of the premises and the mutual promises herein
made, and in consideration of the representations, warranties, and covenants
herein contained, the Parties agree as follows.

1.     DEFINITIONS

1.1    In this Agreement the following words and expressions shall unless the
       context otherwise expressly requires have the meanings set out opposite
       them:-

       "Abbot"                     has the meaning set forth in the preface
                                   above.
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       "Abbot Circular"            the circular to be issued to the
                                   shareholders of Abbot on the date of this
                                   Agreement in the approved terms.

       "the Abbot Group"           means Abbot and all its subsidiaries and
                                   subsidiary undertakings from time to time.

       "Accounts Date"             means 30 September 1995.

       "Act"                       means the Companies Act 1985.

       "Affiliate"                 means in relation to any body corporate, any
                                   subsidiary of such body corporate, any
                                   holding company of such body corporate and
                                   any subsidiary of any such holding company
                                   as such terms are defined in the Act.

       "Ancillary Documents"       means the documents to be executed pursuant
                                   to or in connection with this Agreement.

       "Applicable Rate"           means the National Westminster Bank plc base
                                   rate from time to time.

       "Britannia Bonus"           means any of the following sums which may
                                   become payable by the Independent Operator
                                   to NDESL or any Relevant Party pursuant to
                                   certain provisions of the Britannia
                                   Contract, namely:





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                                   (i)     pursuant to Form 12 (Drilling
                                           Facilities Capex Target and Profit)
                                           of Exhibit 4C to the Britannia
                                           Contract ("the Drilling Facilities
                                           Profit"); and

                                   (ii)    pursuant to Form 12(a) of Exhibit 4C
                                           to the Britannia Contract ("the
                                           Topsides Alliance Incentive").

       "Britannia Bonus Account    means the monthly sum of Pound Sterling 
       Payment"                    6338 payable by the Independent Operator
                                   to NDESL or any Relevant Party pursuant to
                                   paragraph 1.0 of Form 12 (Drilling
                                   Facilities Capex Target & Profit) of Exhibit
                                   4C to the Britannia Contract.
        
       "Britannia Contract"        means contract BRT1-XA1 for detail design of
                                   drilling facilities and drilling operations
                                   and maintenance for the Britannia platform
                                   between NDESL and Chevron U.K. Limited dated
                                   1st November 1994.

       "Buyer"                     means KCA Drilling Group Limited a company
                                   formed and existing under the laws of
                                   England with registered number 1059871.

       "Business Day"              means any day other than a Saturday or a
                                   Sunday on which clearing





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                                   banks in the City of London are open for
                                   business.

       "Cash Portion of the        means the aggregate of (i) L.20,000,000
       Purchase Price"             (ii) US$2,270,000, (iii) Pound Sterling 
                                   294,815 and (iv) the amount in Sterling
                                   equal to the Consolidated Working Capital to
                                   be calculated as provided in Section 2.6 and
                                   (v) an amount in the currency in which it
                                   was paid equal to the Permitted Expenditure.
        
       "Closing"                   has the meaning set forth in Section 2.3
                                   below.

       "Closing Date"              has the meaning set forth in Section 2.3
                                   below.

       "Company"                   has the meaning set forth in the preface
                                   above further details of which are set out
                                   in Part I of Schedule 1.

       "Company Shares"            means all of the issued shares of the
                                   Company and "Company Share" means any one of
                                   them.

       "Conditions"                means the conditions set out in Section 7.

       "Confidential Information"  means any information concerning the
                                   businesses and affairs of the Target Group
                                   that is not already generally available to
                                   the public otherwise than as the result of a
                                   breach of an obligation of





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                                   confidentiality owed to the Target Group,
                                   including, without limitation, information
                                   concerning: the operation of any process;
                                   trade secrets; the manufacture, design or
                                   development of any products; the marketing
                                   of any products or services (including
                                   customer lists, financial information, sales
                                   statistics, survey reports and market share
                                   data); the selection and purchase of any
                                   component part or equipment existing in
                                   whatever form including but not limited to
                                   engineering and chemical data
                                   specifications, formulae, drawings, manuals,
                                   component lists, instructions, designs and
                                   circuit diagrams.

       "Consolidated Working       means the adjusted current net assets of the
       Capital"                    Target Group as at the Closing Date
                                   determined in accordance with the accounting
                                   principles and practices described in
                                   Schedule 2, plus an amount equal to the
                                   Redundancy Adjustment.

       "Consolidated Working       means the statement of Consolidated Working
       Capital Statement"          Capital to be prepared pursuant to Section
                                   2.6 and in accordance with the accounting
                                   principles and practices described in
                                   Schedule 2.





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       "Contracts"                 means those contracts to which the Company
                                   or any of the Subsidiaries is a party which
                                   are listed in (and as amended by the
                                   amendments referred to in) Schedule 3.

       "Disclosure Letter"         means the disclosure letter delivered by the
                                   Seller to the Buyer on the date hereof in
                                   the approved terms.

       "Drill Pipe"                means the drill pipe details of which are
                                   attached as Schedule 10, Part 1.

       "Encumbrance"               means any encumbrance or security interest
                                   of any kind whatsoever including (without
                                   limitation) any mortgage, pledge, lien,
                                   charge, hypothecation, right to acquire,
                                   right of pre-emption, option, conversion
                                   right, third party right or interest, right
                                   of set off or counterclaim, trust
                                   arrangement or retention of title agreement
                                   or similar arrangement.





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       "Estimated Cash Portion     means the aggregate of (i) Pound Sterling 
       of the Purchase Price"      20,000,000, (ii) US $2,270,000, (iii) Pound
                                   Sterling 294,815 and (iv) the amount in
                                   Sterling equal to the estimated amount of
                                   the Consolidated Working Capital to be
                                   calculated as provided in Sections 2.2.2 and
                                   2.6 and (v) an amount in the currency in
                                   which it was paid equal to the amount of any
                                   Permitted Expenditure.
        
       "Estimated Bonus"           means the amount which the Seller estimates
                                   as at the date of this Agreement will be
                                   payable by way of bonus pursuant to the
                                   Britannia Contract being Pound Sterling
                                   985,566 by way of Drilling Facilities Profit
                                   and Pound Sterling 601,537 by way of 
                                   Topsides Alliance Incentive.
        
       "Excluded Assets"           means (i) all of the residential property
                                   owned by the Company or its Subsidiaries,
                                   and (ii) all of the right, title and
                                   interest of the Company and its Subsidiaries
                                   to the assets owned or leased by the branch
                                   of NDESL operating in the United States,
                                   (iii) those tenders and bids and (iv) the
                                   99,900 shares of Pound Sterling 1 each in 
                                   Paloak Limited all as identified in Schedule
                                   5 together with all liabilities of the
                                   Company and its Subsidiaries associated with
                                   items (i) to (v).
        




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       "Financial Statements"      means the audited balance sheets of the
                                   Company and each Subsidiary and the audited
                                   consolidated balance sheets of the Target
                                   Group as at, and the audited profit and loss
                                   accounts and cash flow statement of the
                                   Company and each Subsidiary and the audited
                                   consolidated profit and loss accounts of the
                                   Target Group for the financial periods ended
                                   on, 30 September 1994 and the Accounts Date
                                   together with the notes and directors'
                                   report and auditors' report and all other
                                   documents or statements annexed thereto or
                                   incorporated therein.

       "GAAP"                      means United Kingdom generally accepted
                                   accounting principles as in effect from time
                                   to time.

       "ICTA"                      means the Income and Corporation Taxes Act
                                   1988.

       "Independent Operator"      means Chevron U.K. Limited of 2 Portman
                                   Street, London W1H OAH or any assignee or
                                   successor thereto as party to the Britannia
                                   Contract.

       "Instrumentation"           means the instrumentation details of which
                                   are attached as Schedule 10, Part 2.





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       "Intellectual Property"     means all the intellectual property in any
                                   part of the world used, or required to be
                                   used by the Company or any Subsidiary in, or
                                   in connection with, its business including
                                   but not limited to trade marks, service
                                   marks, patents, utility models, registered
                                   design rights, applications for any of the
                                   foregoing, unregistered trade marks and
                                   service marks, trade and business names
                                   including rights in any get-up or trade
                                   dress, copyright (including rights in
                                   computer software), unregistered design
                                   rights and inventions.

       "Knowledge"                 means the actual knowledge of Mr R.
                                   Stratton, Mr L. Heidt, Mr E. Nelson, Mr G.
                                   Allan, Mr J. Bruce and Mr E. McLeod and any
                                   other matters of which they ought reasonably
                                   in the due performance of their respective
                                   duties in relation to the Target Group to be
                                   aware.

       "Liability for Taxation"    has the meaning set forth in the Tax
                                   Covenant.

       "Licence"                   means a licence, permit, certificate,
                                   consent, approval, registration or
                                   authorisation.


       "London Stock Exchange"     means the London Stock Exchange Limited.





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       "Most Recent Financial      means the unaudited balance sheet of the
       Statements"                 Company and each Subsidiary and the
                                   unaudited consolidated balance sheet of the
                                   Target Group as at, and the unaudited profit
                                   and loss account of the Company and each
                                   Subsidiary and the unaudited consolidated
                                   profit and loss account of the Target Group
                                   for, the financial period ended on the Most
                                   Recent Month End.

       "Most Recent Month End"     means 31 August 1996.

       "NDESL"                     means Nabors Drilling and Energy Services UK
                                   Limited registered in Scotland with company
                                   number 125584 further details of which are
                                   set out in Part 2 of Schedule 1.

       "Notional Tax Rate"         the statutory rate of corporation tax
                                   applicable to the tax period in which the
                                   Britannia Bonus or any part of it is
                                   included in taxable income of NDESL or any
                                   Relevant Party.

       "Ordinary Course of         means the ordinary course of business
       Business"                   consistent with past custom and practice.





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       "Parties"                   has the meaning set forth in the preface
                                   above and "Party" shall mean either one of
                                   them.

       "Permitted Expenditure"     means any capital expenditure made in
                                   accordance with the terms of Section 5.1.

       "Person"                    includes an individual, a partnership, body
                                   corporate, a trust, a joint venture, an
                                   unincorporated association or a governmental
                                   entity (or any department, agency, or
                                   political subdivision thereof) and includes
                                   a reference to that person's legal personal
                                   representatives and successors.

       "Properties"                means the properties details of which are
                                   set out in Schedule 6 and references to a
                                   "Property" include a reference to each of
                                   the individual Properties.

       "Purchase Price"            has the meaning set forth in Section 2.2
                                   below.

       "Redundancy Adjustment"     means a cash sum up to a maximum of
                                   Pound Sterling 150,000 equal to the
                                   aggregate amount paid by the Company or any
                                   of the Subsidiaries in the period from 24
                                   May 1996 until the date of this Agreement in
                                   connection with the termination of
                                   employment of the individuals listed in Part
                                   2 of Schedule 4 by reason of
        




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                                   redundancy (including any legal costs and
                                   expenses associated with any claims made in
                                   connection with such termination of
                                   employment).

       "Registered Intellectual    means any trade marks, service marks or
       Property"                   patents which have been registered at a
                                   public registry.

       "Relevant Party"            means any person to whom any of NDESL's
                                   rights and/or obligations under Britannia
                                   Contract are assigned or any successor of
                                   NDESL as party thereto.

       "Relevant Services"         means the services referred to in Section
                                   11.1.1(ii).

       "Resolutions"               means the shareholders' resolutions in the
                                   approved terms set out in the notice of
                                   extraordinary meeting attached to the Abbot
                                   Circular.

       "Retained Group"            means the Seller and any subsidiary or
                                   subsidiary undertaking of the Seller from
                                   time to time other than any member of the
                                   Target Group.

       "RTPA"                      means the Restrictive Trade Practices Act
                                   1976 and 1977.

       "Seller"                    has the meaning set forth in the preface
                                   above.





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       "Subsidiary"                means either of NDESL and TWSL and
                                   "Subsidiaries" means both of them.

       "subsidiary and             have the meanings given to them respectively
       subsidiary undertaking"     by sections 736 and 258 of the Act.

       "Target Group"              means the Company and each of the
                                   Subsidiaries.

       "Taxation"                  has the meaning given in the Tax Covenant.

       "Taxation Authority"        has the meaning given in the Tax Covenant.

       "Tax Covenant"              means the tax covenant contained in Schedule
                                   7.

       "Tax Refund"                means any tax refund (including any interest
                                   or repayment supplement thereon) to the
                                   extent that such refund relates to the
                                   period before the Closing Date and for the
                                   avoidance of doubt including any tax refund
                                   received in connection with the litigation
                                   referred to in Section 6.2.

       "TCGA"                      means the Taxation of Chargeable Gains Act
                                   1992.





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       "TWSL"                      means Thistle Well Services Limited
                                   registered in Scotland with company number
                                   139344 further details of which are set out
                                   in Part 3 of Schedule 1.

       "VAT"                       means, in the United Kingdom, value added
                                   tax.

       "VATA"                      means the Value Added Tax Act 1994.

       "Warrant"                   means the warrant to be issued by Abbot to
                                   the Seller as of the Closing Date in the
                                   approved terms.

       "Warranties"                means the representations, warranties and
                                   undertakings contained in Sections 3.1 and 4
                                   and references to a "Warranty" shall be
                                   construed accordingly.

1.2    A document expressed to be "in the approved terms" shall mean any
       document which has been signed or initialled for the purposes of
       identification by or on behalf of the Seller and the Buyer.

1.3    In this Agreement, unless the context otherwise requires, reference to:

       1.3.1  a Section or Schedule is a reference to a Section of or Schedule
              to this Agreement;

       1.3.2  a statutory provision includes a reference to that provision as
              modified, replaced, amended and/or re-enacted from time to time
              (whether before or after the date of this Agreement) and any
              prior or subsequent subordinate legislation made under it;





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       1.3.3  "holding company" and "body corporate" have the respective
              meanings attributed to them in sections 736 and 740 of the Act;

       1.3.4  a "company" has the meaning set out in section 735 of the Act;
              and

       1.3.5  a "connected person" is a reference to a person connected with
              another within the meaning of section 839 of ICTA.

1.4    The Schedules form part of this Agreement and shall be interpreted or
       construed as though they were set out in this Agreement.

1.5    The headings to the Sections, Schedules and paragraphs of the Schedules
       are for convenience only and shall not affect the interpretation of this
       Agreement.

2.     PURCHASE AND SALE OF COMPANY SHARES.

2.1    BASIC TRANSACTION. The Seller agrees to sell to the Buyer and the Buyer
       agrees to purchase the Company Shares free from any Encumbrances with
       full title guarantee (provided however that for the purposes of
       interpreting the words "full title guarantee" the provisions of sections
       6(1) and 6(2) of the Law of Property (Miscellaneous Provisions) Act 1994
       ("LPA") shall be deemed not to apply and, other than with regard to
       subsequent transfers of the Company Shares by the Buyer or an Affiliate
       of the Buyer to another Affiliate of the Buyer, the provisions of
       section 7 of the LPA shall also be deemed not to apply.

2.2    PURCHASE PRICE. In consideration of the transfer to the Buyer of the
       Company Shares, (a) the Buyer agrees to pay to the Seller (i) twenty
       million pounds sterling (Pound Sterling 20,000,000), (ii) two million
       two hundred and seventy thousand U.S. Dollars (US$2,270,000), (iii)
       Pound Sterling 294,815 and (iv) the amount in Sterling equal to the
       Consolidated Working Capital as of the
        




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       Closing Date and (v) an amount in the currency in which it was paid
       equal to the amount of any Permitted Expenditure and (b) Abbot agrees at
       the Closing Date to issue to the Seller the Warrant (together the
       "Purchase Price").  The Purchase Price shall be satisfied as follows:

       2.2.1  At Closing, the Buyer shall pay to the Seller the Estimated Cash
              Portion of the Purchase Price by telegraphic transfer of the
              Sterling component and the US Dollar component of the Estimated
              Cash Portion of the Purchase Price in immediately available funds
              into the following account of the Seller: account name Hong Kong
              Bank NY Foreign Exchange; account number 35206696; at Midland
              Bank plc, Swift code MIDL GB22, sort code 40-53-88;

       2.2.2  At least ten calendar days prior to Closing, the Seller shall
              prepare and deliver to the Buyer a statement setting forth (i) an
              estimate of the amount of the Consolidated Working Capital and
              the amount of any Permitted Expenditure, and (ii) a calculation
              of the Estimated Cash Portion of the Purchase Price based upon
              such estimate.  In the event that the Buyer does not agree with
              the Seller's computation, the Buyer shall promptly notify the
              Seller of the same, the Seller shall promptly provide such
              additional information as the Buyer shall reasonably request to
              support such computation, and the Parties shall negotiate in good
              faith and attempt to agree, at least three Business Days prior to
              the Closing Date, upon an acceptable estimate of such amounts.
              Failing any such mutual agreement, the Estimated Cash Portion of
              the Purchase Price delivered at Closing shall be Pound Sterling 
              23,295,000 plus US$2,270,000.

       2.2.3  At Closing, Abbot will issue the Warrant.  Abbot undertakes that
              there shall be no issuance of any equity securities,
              subdivisions, consolidations, exchange of shares, rights issues,





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              reductions of capital or the like of the issued share capital of
              Abbot after the date of this Agreement and on or before the
              Closing Date save for the placing and open offer described in the
              Abbot Circular.

       2.2.4  All stamp duty payable on the purchase of the Company Shares
              shall be borne by the Buyer.

2.3    THE CLOSING.  The closing of the transactions contemplated by this
       Agreement ("CLOSING") shall take place at the offices of Pinsent Curtis,
       69 Old Broad Street, London EC2, England 3 Business Days after the
       Conditions have been satisfied or waived (in accordance with Section 7)
       or such other date as the Parties may mutually determine (the "CLOSING
       DATE").

2.4    DELIVERIES AT THE CLOSING.  At Closing:

       2.4.1  the Seller will deliver to the Buyer:

              2.4.1.1   duly executed transfers of all of the Company Shares in
                        favour of the Buyer together with the relative share
                        certificates;

              2.4.1.2   duly executed transfers in favour of the Company of
                        such shares in the Subsidiaries as are registered in
                        the names of nominee holders, together with the
                        relative share certificates;

              2.4.1.3   a copy, certified to be a true copy by a director or
                        secretary of the Seller, of a resolution of the
                        Seller's board of directors (or an authorised committee
                        of that board) authorising the execution and completion
                        of this





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                        Agreement and the execution of the Ancillary Documents
                        to which it is a party;

              2.4.1.4   duly executed power(s) of attorney in favour of the
                        Buyer, or the Company in relation to the Subsidiaries,
                        in the approved terms to enable the Buyer and the
                        Company pending registration as the holder of the
                        Company Shares or the shares in the Subsidiaries (as
                        the case may be) to exercise all voting and other
                        rights attaching to the Company Shares and the shares
                        in the Subsidiaries;

              2.4.1.5   the title deeds and documents relating to each of the
                        Properties as listed on Schedule 6 (which obligation
                        shall be deemed satisfied by making them available at
                        the offices of Paull & Williamsons at 6 Union Row,
                        Aberdeen, Aberdeenshire AB1 1SA);

              2.4.1.6   a document from Hancock Mutual Life Insurance Company
                        (and any Affiliates) ("Hancock") evidencing the release
                        and discharge of all charges over the shares and assets
                        of the Target Group and all guarantees given to Hancock
                        by the Target Group together with the appropriate form
                        under the Act evidencing the release and discharge of a
                        charge dated 26 August 1992 in favour of the Royal Bank
                        of Scotland plc over the assets of TWSL;

              2.4.1.7   a deed of acknowledgement from the Seller in the
                        approved terms that all inter-group indebtedness
                        between the Retained Group on the one hand and the
                        Target Group on the other has been discharged in full;





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              2.4.1.8   a legal opinion from Baker & McKenzie, New York in
                        substantially the approved terms relating to the
                        Seller;

              2.4.1.9   the resignation of Coopers & Lybrand as the auditors of
                        each member of the Target Group, such resignation to
                        contain a statement in accordance with Section 394 of
                        the Act that there are no circumstances connected with
                        their ceasing to hold office which they consider should
                        be brought to the attention of the members or creditors
                        of the relevant member of the Target Group;

              2.4.1.10  all the statutory books (duly written up to date) of
                        the Company and the Subsidiaries and their respective
                        certificates of incorporation and on change of name (if
                        any) and common seals;

              2.4.1.11  letters of resignation in the approved terms from each
                        of the directors and the secretary of the Company and
                        the directors and secretary of each of the
                        Subsidiaries, such resignations to take effect from
                        close of the meeting of the board of directors of the
                        Company referred to in Section 2.4.4 and letters of
                        resignation in the approved terms from those of the
                        Excluded Employees who have accepted employment with
                        the Retained Group;

              2.4.1.12  the latest inspection reports in respect of the Drill
                        Pipe;

              2.4.1.13  the Buyer will deliver to the Seller the Estimated Cash
                        Portion of the Purchase Price in accordance with the
                        payment instructions specified in Section 2.2.1;





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              2.4.1.14  the Buyer will deliver to the Seller a legal opinion
                        from a reputable firm of lawyers admitted in the
                        practice of the Isle of Man in substantially the
                        approved terms.

       2.4.2  Abbot will issue to the Seller the Warrant;

       2.4.3  the Seller shall cause the directors of the Company to hold a
              meeting of the board of directors of the Company at which they
              shall pass resolutions in the approved terms (inter alia) to:-

              2.4.3.1   approve the registration of the Buyer as a member of
                        the Company subject only to the production of duly
                        stamped transfers in respect of the Company Shares;

              2.4.3.2   accept the resignations referred to in Section 2.4.1.11
                        and appoint such persons as the Buyer may nominate as
                        directors and secretary of the Company;

              2.4.3.3   revoke all authorities to the bankers of the Company
                        relating to bank accounts and give authority to such
                        persons as the Buyer may nominate to operate the same.

       2.4.4  the Seller shall procure that a board meeting of each of the
              Subsidiaries is held at which the directors:

              2.4.4.1   approve the registration of the Company as a member of
                        its Subsidiaries in respect of, and subject only to the
                        production of duly stamped transfers of, the shares
                        referred to in Section 2.4.1.2;





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              2.4.4.2   accept the resignations referred to in Section 2.4.1.12
                        in respect of the relevant Subsidiary and appoint the
                        persons nominated by the Buyer as directors and
                        secretary of the Subsidiary;

              2.4.4.3   revoke all existing authorities to bankers relating to
                        the operation of the Subsidiary's bank accounts and
                        give authority in favour of the person nominated by the
                        Buyer to operate such account.

2.5    If Closing does not proceed on the date set for Closing in Section 2.3
       (or on the date to which Closing is postponed pursuant to Section 2.5.2)
       because any Party fails to discharge fully any of its obligations under
       this Section 2 or under Sections 5.5 to 5.8, the Buyer in the case of
       failure by the Seller or the Seller in the case of failure by the Buyer
       or Abbot may, without prejudice to any other remedies available except
       as such remedies are limited in Section 5.4, by notice to the other
       elect to:

       2.5.1  proceed to Closing so far as practicable; or

       2.5.2  postpone Closing to such date as the non-defaulting Party
              specifies being not later than 21 November 1996 in which event
              the provisions of this Agreement apply as if that other date is
              the date set for Closing in Section 2.3; or

       2.5.3  terminate this Agreement in which event the provisions of Section
              9.2 shall apply.





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2.6    POST-CLOSING ADJUSTMENT.

       2.6.1  On or before the date that is 125 calendar days following the
              Closing Date (or the next Business Day if such date is not a
              Business Day), the Buyer will prepare and deliver to the Seller a
              statement ("the Consolidated Working Capital Statement") showing
              the actual amount of the Consolidated Working Capital together
              with the amount of any Permitted Expenditure.  The Seller shall
              use all reasonable endeavours to procure that Coopers & Lybrand
              shall grant to the Buyer access to their working papers for the
              Seller and for the Retained Group to the extent reasonably
              required to enable the Buyer to prepare the Consolidated Working
              Capital Statement and the Seller shall promptly make available to
              the Buyer all information which is in the possession of the
              Retained Group which may reasonably be required to prepare the
              Consolidated Working Capital Statement.

       2.6.2  The Buyer shall make available to the Seller all information
              which shall be in the possession of the Buyer or any member of
              the Target Group and shall use all reasonable endeavours to
              procure that the accountants acting on behalf of the Buyer in
              connection with the preparation of the Working Capital Statement
              shall grant to the Seller access to their working papers in
              respect of the Working Capital Statement to the extent reasonably
              required by the Seller for the Seller to verify whether the
              Consolidated Working Capital Statement is correct.  Within 30
              calendar days following delivery of the Consolidated Working
              Capital Statement to the Seller, the Seller shall notify the
              Buyer whether it agrees with the Consolidated Working Capital
              Statement.  If the Seller disagrees with the Consolidated Working
              Capital Statement, the Seller shall provide the Buyer with a
              written notice specifying the basis for the Seller's





                                       22
<PAGE>   23
              disagreement, and the Seller and the Buyer shall work in good
              faith to reach agreement on the amount of the Consolidated
              Working Capital.  In the absence of a written notice from the
              Seller to the Buyer, specifying the basis for the Seller's
              disagreement, the Seller shall be deemed to have agreed the
              amount of the Consolidated Working Capital contained in the
              Consolidated Working Capital Statement delivered to it pursuant
              to Section 2.6.1.

       2.6.3  If the Buyer and the Seller fail to reach agreement on the amount
              of the Consolidated Working Capital within 30 calendar days
              following the date of written notice given in accordance with
              clause 2.6.2, either the Seller or the Buyer may cause the matter
              to be referred to one of the "Big Six" independent public
              accounting firms as the Seller and the Buyer may mutually agree.
              In default of agreement within 3 Business Days of one party
              nominating a firm, any Party shall be entitled to request the
              President of the Institute of Chartered Accountants in England
              and Wales to select such independent accounting firm (other than
              Coopers & Lybrand and Arthur Andersen).  The fees and
              disbursements of such accountants shall be borne equally by the
              Buyer and the Seller.  Such accountants shall examine the records
              of the Seller, the Target Group and the Buyer, and, no later than
              90 calendar days following the date upon which such matter shall
              be referred to such accountants, such accountants shall determine
              the amount of the Consolidated Working Capital and the amount of
              any Permitted Expenditure.  Any such determination (i) shall
              (except as to any manifest error) be final and binding on the
              Parties, and (ii) may be enforced by appropriate judicial or
              other proceedings.





                                       23
<PAGE>   24
       2.6.4  The Cash Portion of the Purchase Price shall reflect any such
              determination by such accountants.  If the Cash Portion of the
              Purchase Price (whether by agreement of the Parties or after
              giving effect to any such determination by such accountants)
              exceeds the Estimated Cash Portion of the Purchase Price paid at
              the Closing, the Buyer shall pay to the Seller the amount of such
              excess plus interest thereon from the Closing Date until paid at
              the Applicable Rate.  If the Cash Portion of the Purchase Price
              (whether by agreement of the Parties or after giving effect to
              any such determination by such accountants) is less than the
              Estimated Cash Portion of the Purchase Price paid at the Closing,
              the Seller shall pay to the Buyer the amount of such shortfall
              plus interest thereon from the Closing Date until paid at the
              Applicable Rate.  Such payment shall be made, in either case,
              within 15 calendar days following the agreement of the Parties or
              the final determination of the Cash Portion of the Purchase Price
              by such accountants.  All of such interest shall be computed on
              the basis of the actual number of days elapsed in a year of 365
              or 366 days, as the case may be.

3.     REPRESENTATIONS AND WARRANTIES CONCERNING THE TRANSACTION.

3.1    REPRESENTATIONS AND WARRANTIES OF THE SELLER. The Seller represents and
       warrants to the Buyer that the statements contained in this Section 3.1
       are  true and   accurate as of the date of this Agreement except as
       fairly set forth in  the Disclosure Letter.

       3.1.1  ORGANIZATION OF SELLER. The Seller is duly organized and validly
              existing under the laws of the jurisdiction of its incorporation.

       3.1.2  AUTHORISATION OF TRANSACTION. The Seller has full power and
              authority to execute and deliver this Agreement and each of the
              Ancillary Documents to which it is a party and to perform its





                                       24
<PAGE>   25
              obligations thereunder.  This Agreement and each of the Ancillary
              Documents to which it is a party constitute the valid and legally
              binding obligation of the Seller, enforceable in accordance with
              their respective terms and conditions.  The Seller need not give
              any notice to, make any filing with, or obtain any authorisation,
              consent, or approval of any government or governmental agency in
              order to consummate the transactions contemplated by this
              Agreement.

       3.1.3  NONCONTRAVENTION.  Neither the execution and the delivery of  the
              Agreement or the Ancillary Documents to which it is a party, nor
              the consummation of the transactions contemplated thereby, will
              (i) violate any constitution, statute, regulation, rule,
              injunction, judgment, order, decree, ruling, charge, or other
              restriction of any government, governmental agency, or court to
              which the Seller is subject or (ii) violate any provision of
              Seller's charter or bylaws or (iii) conflict with, result in a
              breach of, constitute a default under, result in the acceleration
              of, create in any party the right to accelerate, terminate,
              modify, or cancel, or require any notice under any agreement,
              contract, lease, license, instrument, or other arrangement to
              which the Seller is a party or by which it is bound or to which
              any of its assets is subject.

       3.1.4  BROKERS' FEES. The Seller has no liability or obligation to pay
              any fees or commissions to any broker, finder, or agent with
              respect to the transactions contemplated by this Agreement for
              which the Buyer could become liable or obligated.

3.2    REPRESENTATIONS AND WARRANTIES OF THE BUYER. The Buyer represents and
       warrants to the Seller that the statements contained in this Section 3.2
       are true and  accurate as of the date of this Agreement.





                                       25
<PAGE>   26
       3.2.1  ORGANIZATION OF THE BUYER.  The Buyer is a corporation duly
              incorporated under English law.

       3.2.2  AUTHORISATION OF TRANSACTION.  The Buyer has full power and
              authority to execute and deliver this Agreement and each of the
              Ancillary Documents to which it is a party and to perform its
              obligations thereunder.  This Agreement and each of the Ancillary
              Documents to which it is a party constitutes the valid and
              legally binding obligation of the Buyer, enforceable in
              accordance with its terms and conditions. The Buyer need not give
              any notice to, make any filing with, or obtain any authorisation,
              consent, or approval of any government or governmental agency in
              order to consummate the transactions contemplated by this
              Agreement.

       3.2.3  NONCONTRAVENTION.  Neither the execution and the delivery of this
              Agreement or the Ancillary Documents to which it is a party, nor
              the consummation of the transactions contemplated hereby, will
              (i) violate any constitution, statute, regulation, rule,
              injunction, judgment, order, decree, ruling, charge, or other
              restriction of any government, governmental agency, or court to
              which the Buyer is subject or (ii) violate any provision of its
              Memorandum or Articles of Association or (iii) conflict with,
              result in a breach of, constitute a default under, result in the
              acceleration of, create in any party the right to accelerate,
              terminate, modify, or cancel, or require any notice under any
              agreement, contract, lease, license, instrument, or other
              arrangement to which the Buyer is a party or by which it is bound
              or to which any of its assets is subject.

       3.2.4  BROKERS' FEES.  The Buyer has no liability or obligation to pay
              any fees or commissions to any broker, finder, or agent with





                                       26
<PAGE>   27
              respect to the transactions contemplated by this Agreement for
              which the Seller could become liable or obligated.

3.3    REPRESENTATIONS AND WARRANTIES OF ABBOT.  Abbot represents and warrants
       to the Seller that the statements contained in this Section 3.3 are true
       and accurate as of the date of this Agreement.

       3.3.1  ORGANIZATION OF ABBOT.  Abbot is a corporation duly incorporated
              under English law.

       3.3.2  AUTHORISATION OF TRANSACTION.  Abbot has full power and authority
              to execute and deliver this Agreement and to perform its
              obligations hereunder and, without limitation, to issue the
              Warrant to the Seller on the Closing Date and to comply with its
              obligations thereunder. This Agreement and each of the Ancillary
              Documents to which it is a party constitutes the valid and
              legally binding obligation of Abbot, enforceable in accordance
              with its terms and conditions. Abbot need not give any notice to,
              make any filing with, or obtain any authorisation, consent, or
              approval of any other person in order to consummate the
              transactions contemplated by this Agreement.

       3.3.3  NONCONTRAVENTION.  Neither the execution and the delivery of this
              Agreement or the Ancillary Documents to which it is a party, nor
              the consummation of the transactions contemplated hereby, will
              (i) violate any constitution, statute, regulation, rule,
              injunction, judgment, order, decree, ruling, charge, or other
              restriction of any government, governmental agency, or court to
              which Abbot is subject or (ii) violate any provision of its
              Memorandum or Articles of Association or (iii) conflict with,
              result in a breach of, constitute a default under, result in the
              acceleration of, create in any party the right to accelerate,
              terminate, modify, or cancel, or require any notice under any





                                       27
<PAGE>   28
              agreement, contract, lease, license, instrument, or other
              arrangement to which Abbot is a party or by which it is bound or
              to which any of its assets is subject.

       3.3.4  BROKERS' FEES.  Abbot has no liability or obligation to pay any
              fees or commissions to any broker, finder, or agent with respect
              to the transactions contemplated by this Agreement for which the
              Seller could become liable or obligated.

       3.3.5  CAPITALIZATION. The authorised share capital of Abbot is
              Pound Sterling 31,500,000 comprising 185,000,000 ordinary shares
              of 15 pence each and 3,750,000 convertible preference shares of
              Pound Sterling 1 each of which 108,064,471 ordinary shares and
              3,750,000 convertible preference shares are issued and are fully
              paid.  Upon the successful completion of the placing and open
              offer referred to in the Abbot Circular, Abbot's authorised share
              capital will be Pound Sterling 31,500,000, comprising 185,000,000
              ordinary shares of 15 pence each and 3,750,000 convertible
              preference shares of Pound Sterling 1 each of which 130,277,365
              ordinary shares and 3,750,000 convertible preference shares will
              be issued and fully paid.
        
3.4    The representations and warranties contained in Sections 3.2.2, 3.2.3,
       3.3.2 and 3.3.3 insofar as they relate to the performance of the
       obligations of Abbot and the Buyer in Sections 2.2, 2.4.2 and 2.4.3 are
       given subject to the satisfaction of the Conditions in Section 7.1.1 and
       7.1.2.





                                       28
<PAGE>   29
4.     REPRESENTATIONS AND WARRANTIES CONCERNING THE COMPANY AND ITS
       SUBSIDIARIES.

4.1    The Seller represents and warrants to the Buyer that the statements
       contained in  Schedule 8 are true and accurate as of the date of this
       Agreement and except as fairly set forth in the Disclosure Letter, or as
       set forth in this Agreement or any Schedule to this Agreement.

4.2    Save as provided in the Disclosure Letter and save for any information
       within the actual knowledge of any executive member of the Board of
       Directors of Abbot (which information shall be deemed to be known to the
       Buyer), no information of which Abbot or the Buyer has knowledge shall
       prejudice any claim being made by the Buyer under any of the Warranties,
       nor shall it affect the amount recoverable under any such claim and,
       subject thereto, neither the rights and remedies of the Buyer, nor the
       Seller's liability in respect of the Warranties shall be affected by any
       investigation made by or on behalf of the Buyer into the Target Group.

4.3    Each of the Warranties shall be interpreted as a separate and
       independent Warranty and shall not be deemed to be limited by reference
       to any other Warranty.

4.4    No information supplied by, or on behalf of, the Company or its
       Subsidiaries to the Seller or its advisers in connection with the
       business and affairs of the Target Group constitutes a representation,
       warranty or undertaking to the Seller as to its accuracy by the Company
       or its Subsidiaries and the Seller waives each and every claim which it
       may have against the Company, its Subsidiaries or their respective
       employees in respect of such information.





                                       29
<PAGE>   30
5.     PRE-CLOSING COVENANTS.

The Parties agree as follows with respect to the period between the execution
of this Agreement and the Closing.

5.1    OPERATION OF BUSINESS.  The Seller shall procure that the Company and
       its Subsidiaries shall, save to the extent required or permitted by this
       Agreement or to enable the Seller to perform its obligations under this
       Agreement including its obligations to procure the transfer of the
       Excluded Assets, the Drill Pipe and the Instrumentation and the
       discharge of all bank indebtedness and intercompany accounts pursuant to
       Sections 5.5 to 5.8, conduct its business only in the Ordinary Course of
       Business so as to maintain it as a going concern and shall not without
       the prior written consent of the Buyer;

       5.1.1  create, allot, issue, repay, redeem or grant any options over any
              share or loan capital of the Company or its Subsidiaries or agree
              to do any of those things;

       5.1.2  acquire or dispose of or agree to acquire or dispose of any share
              or other interest in any company, partnership or other venture;

       5.1.3  acquire or dispose of or agree to acquire or dispose of any
              individual fixed asset with a book value in excess of Pound
              Sterling 5,000 nor fixed assets with an aggregate book value 
              in excess of Pound Sterling 100,000;

       5.1.4  declare, make or pay any dividend or other distribution;

       5.1.5  pass a shareholders' resolution;





                                       30
<PAGE>   31
       5.1.6  create, or agree to create, an Encumbrance over any asset or
              redeem, or agree to redeem, an existing Encumbrance over any
              asset;

       5.1.7  acquire or dispose of any freehold or leasehold property or grant
              or terminate any lease or third party right (including Licences)
              in respect of any of the Properties nor agree to do any of those
              things or change the existing use of the Properties or change or
              agree to change the terms of any lease or third party rights in
              respect of the Properties or the rents or fees payable
              thereunder;

       5.1.8  make or agree to make any amendment to any of the Contracts which
              amendment has the effect of increasing costs to the Target Group
              or decreasing revenues to the Target Group in an aggregate value
              on an annualised basis in excess of Pound Sterling 50,000, or 
              terminate any of the Contracts;

       5.1.9  amend the terms of employment of any employee of the Target Group
              (including as to pension commitments and share options) or offer
              to engage any new employee or consultant at an annual salary or
              fee (on the basis of full time engagement) in excess of Pound 
              Sterling 25,000 or dismiss any Employee save for the hiring or
              dismissal of offshore employees where such action is reasonably
              required to enable the Target Group to comply with its
              obligations under any Contract or other drilling contract (if
              any);
        
       5.1.10 compromise, settle, release, discharge or compound any litigation
              or arbitration proceedings except where the costs of such
              litigation or arbitration proceedings are to be borne by the
              Seller pursuant to the terms of Section 6.2 of this Agreement in





                                       31
<PAGE>   32
              which case the Seller shall have absolute discretion in the
              handling of such proceedings;

       5.1.11 enter into any new contracts for the provision of labour services
              for drilling platforms or enter into any other contracts for the
              supply of goods or services with an annual revenue or cost in
              excess of Pound Sterling 50,000;

       provided that (i) where any capital expenditure is made by the Target
       Group which is not in breach of this Section 5.1 after the date of this
       Agreement and prior to Closing such sum shall be added to the Purchase
       Price as Permitted Expenditure payable by the Buyer, and (ii) this
       Section 5.1 shall not prevent the Seller making any ex-gratia payment
       to, or granting or permitting to be exercised any option over shares
       (other than shares in any company in the Target Group) by, any employee
       of the Target Group or from offering employment with the Retained Group
       to the employees listed in Schedule 4, Part 1.

5.2    OWNERSHIP OF SHARES.  In the period prior to Closing, the Seller will
       retain the entire legal and beneficial ownership of the Company Shares
       and of the entire issued share capital of the Subsidiaries (subject to
       legal title held by nominee shareholders as set out in Parts 2 and 3 of
       Schedule 1).

5.3    NOTIFICATION.  The Seller undertakes prior to Closing to notify
       immediately the Buyer in writing if it becomes aware that any of the
       circumstances set out in paragraphs (i), (ii) or (iv) of Section 5.4
       have arisen or will arise.

       5.3.1  REMEDIES FOR BREACH.  Notwithstanding any breach by the Seller of
              a provision of this Agreement including any breach of the
              Warranties, the Buyer shall proceed to Closing and shall not be
              entitled in any circumstances to rescind or terminate this
              Agreement, save in the case





                                       32
<PAGE>   33
              of (i) fraud by the Seller or (ii) the Seller not having
              disclosed to the Buyer prior to the date of this Agreement the
              fact that it had given or received notice of termination of any
              Contract or that any Contract had been terminated or (iii) the
              Seller not having complied with its obligations under Sections
              2.4.1, 2.4.4 and 2.4.5 or under Sections 5.5 to 5.8 at or prior
              to Closing or (iv) the Seller failing to deliver the Company
              Shares at Closing in accordance with the provisions of Section
              2.1 or failing to deliver the shares of the Subsidiaries in
              accordance with paragraph 5.1 of Schedule 8.

       5.3.2  If the Buyer decides to proceed to Closing and not to exercise
              its right of rescission this shall be without prejudice to any
              rights the Buyer may have to claim damages for breach of contract
              or to exercise any other right or remedy, whether under this
              Agreement or otherwise, resulting from a breach of this Agreement
              or the Warranties, but subject in each case to all other
              limitations on the Seller's liability contained in this
              Agreement.  The Buyer shall in no circumstances be entitled to
              rescind this Agreement after Closing.

5.4    BORROWED FUNDS.  Seller shall procure that, as of the Closing Date, no
       member of the Target Group shall have any indebtedness to any bank or
       other financial institution.

5.5    EXCLUDED ASSETS.  To the extent that such assignments or transfer have
       not occurred prior to the date hereof the Seller shall prior to Closing
       cause each member of the Target Group to assign or transfer to a member
       of the Retained Group all Excluded Assets (whether paid in cash or left
       outstanding as an intercompany debt, but subject always to compliance
       with Section 5.5) and any such assignment or transfer shall be permitted
       without the consent of the Buyer, provided however, that:-

       5.5.1  if any such assignment or transfer shall be prohibited without
              the consent of a third party and such consent shall not have





                                       33
<PAGE>   34
              been obtained prior to the Closing, then (i) such assignment or
              transfer shall not be completed prior to the Closing, (ii), from
              and after the Closing, the Buyer and the Seller will use all
              reasonable commercial efforts to obtain such third-party consent,
              (iii), if the Buyer obtains such third-party consent, the Buyer
              will cause the company which owns such Excluded Asset to transfer
              such Excluded Asset to the Seller or its designee for the
              consideration attributed to it in Schedule 5, pursuant to a deed
              or other assignment document reasonably acceptable to the Seller
              and the Buyer.  The Seller shall indemnify and keep indemnified
              the Buyer and its Affiliates from and against any claims,
              proceedings, costs and liability (other than any liability
              arising out of any action of the Buyer, any of its Affiliates or
              any member of the Target Group from and after the Closing)
              arising out of (A) the ownership of such Excluded Asset, and (B)
              any such transfer; and

       5.5.2  the Seller shall not be obliged to cause NDESL to transfer the
              99,900 shares of L.1,00 each in Paloak Limited, but shall be
              entitled to do so if it so desires.

5.6    ACCOUNTS WITH AFFILIATES.  Prior to Closing, the Seller shall procure
       that, as of the Closing Date, all intercompany loan accounts or
       indebtedness including any trading accounts between (i) the Retained
       Group and (ii) the Target Group are discharged in full.

5.7    DRILL PIPE AND INSTRUMENTATION.  The Seller shall procure that prior to
       Closing the Drill Pipe and the Instrumentation shall be transferred to
       NDESL free from any Encumbrance and with full title guarantee, but with
       the provisions of Sections 6(1) and 6(2) of the LPA disapplied and,
       other than with regard to subsequent transfers between NDESL and an
       Affiliate or between Affiliates of NDESL, with the provisions of Section
       7 of the LPA disapplied (subject, in the case of the Instrumentation, to
       a





                                       34
<PAGE>   35
       contract right in favour of Elf Caledonia Limited) for an aggregate cash
       price payable by NDESL (excluding any VAT, if applicable) of two million
       two hundred and seventy thousand US dollars (US$2,270,000) and two
       hundred and ninety-four thousand eight hundred and fifteen pounds
       (Pound Sterling 294,815).  The Seller shall also procure the assignment 
       to NDESL (to the extent such rights are capable of assignment) of all 
       such manufacturer's rights, warranties and guarantees as may be 
       available to the transferor in connection with the Instrumentation.

5.8    CHANGE OF CORPORATE NAMES.  The Buyer acknowledges that the Seller may
       cause the Company and the Subsidiaries at or prior to Closing to effect
       changes to their respective names to remove therefrom the name "Nabors".
       Abbot undertakes that no member of the Abbot Group shall at any time use
       such name or the names "Sundowner" or "Canrig" or any substantially or
       confusingly similar name, or any trademark, logo or symbol that includes
       or is otherwise associated with any such name, for any purpose,
       including without limitation in connection with the marketing of any
       products or services by the Target Group; and insofar as changes to such
       names have not been effected at or prior to Closing, the Buyer shall
       procure that all necessary steps are taken to complete such changes of
       names within 5 Business Days from Closing.  Notwithstanding the
       foregoing, the Buyer may, for a period not exceeding 90 days immediately
       following Closing, use machinery and equipment that has affixed thereto
       the name "Nabors" provided, however, that (i) the Buyer shall use all
       reasonable endeavours to erase, cover or remove such name as soon as
       possible after Closing and (ii) the Buyer shall indemnify and hold
       harmless the Seller and any member of the Retained Group from and
       against any loss, liability, damage or claim that the Seller or any
       member of the Retained Group may suffer as a result of such use by the
       Buyer of such names, trademarks, logos or symbols.





                                       35
<PAGE>   36
5.9    FULL ACCESS. The Seller will permit, and the Seller will cause each of
       the Company and its Subsidiaries to permit, representatives of the Buyer
       to have access at all reasonable times subject to reasonable notice, and
       in a manner so as not to interfere unnecessarily with the normal
       business operations of the Company and its Subsidiaries, to all
       premises, properties, personnel, books, records (including tax records),
       contracts, and documents of or pertaining to each of the Company and its
       Subsidiaries other than to the Excluded Assets.  The Buyer will treat as
       confidential and hold as such any Confidential Information it receives
       from the Seller, the Company, and its Subsidiaries in the course of the
       reviews contemplated by this Section 5.10, will not at any time
       hereafter use any of the Confidential Information or disclose or divulge
       any such Confidential Information except in connection with this
       Agreement or to meet the requirements of the London Stock Exchange or
       other governmental or regulatory authorities, and, if this Agreement is
       terminated for any reason whatsoever, will return to the Seller, the
       Company, and its Subsidiaries all tangible embodiments (and all copies)
       of the Confidential Information which are in its possession.

6.     POST-CLOSING COVENANTS.

The Parties agree as follows with respect to the period following the Closing.

6.1    GENERAL. In case at any time after the Closing any further action is
       necessary to carry out the purposes of this Agreement, each of the
       Parties will take such further action (including the execution and
       delivery of such further instruments and documents) as the other Party
       reasonably may request, all at the sole cost and expense of the
       requesting Party.

6.2    TAX LITIGATION. For the avoidance of doubt and, notwithstanding any of
       the terms of the agreement between Loffland Brothers North Sea, Inc.





                                       36
<PAGE>   37
       and NDESL dated 21 September 1990 providing for the transfer of the
       business and assets of Loffland Brothers North Sea, Inc. to NDESL,
       nothing in this Agreement shall limit or restrict the rights of the
       Seller or Loffland Brothers North Sea, Inc. to conduct, compromise,
       settle or resist the High Court litigation (number CH 1996 G4108) and
       any related litigation in whatsoever manner it sees fit and without any
       need to refer to, consult or seek or obtain any consent or approval of
       the Buyer, NDESL, or their respective successors or assigns in relation
       thereto.  The Buyer shall procure that neither it nor NDESL nor any of
       their respective successors or assigns shall in any way so limit or
       restrict the rights of or impose any obligations upon the Seller or
       Loffland Brothers North Sea Inc in relation to such litigation.  The
       Buyer shall further procure that neither it nor NDESL nor any of their
       respective successors or assigns shall demand payment from the Inland
       Revenue or assert any right to receive payment from the Inland Revenue
       in relation thereto without having obtained the prior consent in writing
       of Loffland Brothers North Sea, Inc.  The Seller shall indemnify and
       keep indemnified the Buyer and the Target Group from and against any
       claims, proceedings, liability, damages, costs and expenses which the
       Buyer or the Target Group may incur or suffer in relation to the
       litigation referred to in this Section 6.2 whatsoever.

6.3    TAX RETURNS. 

       6.3.1  The Seller or its duly authorised agent shall prepare the tax
              returns of the Company and its Subsidiaries for the accounting
              periods ended on or prior to 30 September 1996.

       6.3.2  The Buyer shall procure that the Company and its Subsidiaries
              shall cause the returns mentioned in Section 6.3.1 to be
              authorised, signed and submitted to the appropriate authority
              without amendment or with such amendments as the Seller shall
              agree provided that the Buyer shall not be obliged to procure
              that the Company and its Subsidiaries take any such action as is
              mentioned in this Section 6.3.2 in relation to any tax return
              that is not true and accurate in all material respects.





                                       37
<PAGE>   38
       6.3.2  Subject to Section 6.3.4 the Seller or its duly authorised agent
              shall prepare all documentation and deal with all matters
              (including correspondence) relating to the tax returns of the
              Company and its Subsidiaries for all accounting periods ended on
              or prior to 30 September 1996 and the Buyer shall procure that
              the Company and its Subsidiaries shall afford such access at all
              reasonable times subject to reasonable notice and in a manner so
              as not to interfere unnecessarily with the normal business
              operations of the Company and its Subsidiaries to such books,
              accounts and records as the Seller may require to enable the
              Seller or its duly authorised agent to prepare those returns and
              conduct matters relating thereto in accordance with the Seller's
              rights under this Section.

       6.3.3  The Seller shall keep the Buyer fully informed as to any action
              taken or proposed to be taken in conjunction with Section 6.3.3.

       6.3.4  The Buyer shall afford the Seller the opportunity to make such
              amendments as the Seller reasonably believes are necessary to the
              tax return or tax returns that relate to the period from 1
              October 1996 to Closing provided that the Buyer shall not be
              obliged to procure that the Company and its subsidiaries take any
              such action in relation to any tax return that is not true and
              accurate in all material respects.

       6.3.5  The Buyer shall keep the Seller informed as to any action taken
              or proposed to be taken in conjunction with Section 6.3.5 and
              shall not submit any documentation or correspondence to the
              relevant Taxation Authority until the Seller has approved them,
              such approval not to be unreasonably withheld or delayed.





                                       38
<PAGE>   39
6.4    RELEASE OF GUARANTEES. Abbot shall and shall procure that the Abbot
       Group and the Target Group shall use their respective reasonable
       endeavours to procure that as soon as practicable after Closing the
       Seller and all members of the Retained Group shall be released from any
       guarantee or surety (whether or not listed in Part 1 of Schedule 9 and
       where not so listed as soon as practicable after Abbot or any member of
       Abbot's Group becoming aware of the existence of such guarantee or
       surety) given by any of them to any third party in respect of the
       performance of the obligations of any member of the Target Group under
       the terms of any agreements entered into by any of them which endeavours
       shall include the offering by Abbot of a guarantee in identical terms in
       substitution for the guarantee of the relevant member of the Retained
       Group and pending such release shall indemnify and keep indemnified the
       Seller for itself and as trustee for all members of the Retained Group
       against any and all liabilities, costs, claims, proceedings and damages
       which may arise in connection with any guarantee or surety given in
       respect of the performance of the obligations of any member of the
       Target Group (whether or not listed in Part 1 of Schedule 9) other than
       to the extent that they arise out of any default of the Seller or any
       member of the Retained Group or any member of the Target Group prior to
       Closing.

       6.4.1  On the Closing Date Abbot shall (i) pay to the Seller the sum of
              Pound Sterling 125,000 in the same manner as the Sterling 
              payment is made under Section 2.2.1 or in a manner otherwise
              agreed between Abbot and the Seller (ii) include (and during the
              following six months maintain the inclusion of) each member of
              the Retained Group which is listed as a guarantor in Part I of
              Schedule 9 as an additional insured on such insurance policies as
              are required to comply with the obligations of the Target Group
              under the relevant Contracts, and (iii) at Seller's request,
              supply copies of certificates evidencing the same.  Upon the
              expiry of six months from the Closing Date and on each
              anniversary of such date (or the first subsequent Business Day
              thereafter if such anniversary is
        




                                       39
<PAGE>   40
              not a Business Day) ("the Anniversary Date"), unless on that date
              all members of the Retained Group have been released from all
              guarantees referred to in Section 6.4.1, Abbot shall (i) pay to
              the Seller the sum of Pound Sterling 250,000 in the same manner
              as the Sterling payment is made under Section 2.2.1 or in a
              manner otherwise agreed between Abbot and the Seller and (ii)
              procure that each member of the Retained Group which is listed as
              guarantor in Part 1 of Schedule 9 continues until the following
              Anniversary Date to be included as an additional insured on such
              policies aforesaid and (iii) at the Seller's request supply
              copies of certificates evidencing the same.
        
       6.4.2  In the event that all of the guarantees referred to in Section
              6.4.1 have been released prior to the expiry of six months from
              the Closing Date or prior to the expiry of twelve months from any
              Anniversary Date upon which the last payment was made under
              Section 6.4.2, the Seller shall refund to Abbot such percentage
              of Pound Sterling 125,000 (in the case of the six months
              following the Closing Date) or such percentage of Pound Sterling
              250,000 (in the case of the twelve months between any two
              Anniversary Dates) as is equal to the percentage which the
              unexpired portion of such period represents of the whole of such
              period.
        
       6.4.3  The Seller shall use all reasonable endeavours to procure that as
              soon as practicable after Closing the Target Group shall be
              released from all guarantees and sureties given by any member of
              the Target Group to any third party in respect of the performance
              of the obligations of any member of the Retained Group under the
              terms of any agreements entered into by any of them, which
              includes without limitation those listed in Part 2 of Schedule 9,
              which endeavours shall include the offering by the Seller of a
              guarantee in identical terms in substitution for the guarantee of
              the relevant member of the Target Group and pending such release
              shall indemnify and keep indemnified the Buyer for itself and as
              trustee for all members of the Target Group against any and all
              liabilities, costs, claims, proceedings and damages





                                       40
<PAGE>   41
       which may arise in connection with any such guarantee or surety other
       than to the extent that they arise out of any default of the Abbot Group
       or any member of the Target Group after Closing.
        
6.5    BRITANNIA CONTRACT.  The Buyer shall procure that:

       6.5.1  NDESL and any Relevant Party shall with effect from Closing
              perform all its outstanding obligations under the Britannia
              Contract in the Ordinary Course of Business and so as to ensure
              that the amount of and the timing of payment of the Britannia
              Bonus shall not be adversely affected;

       6.5.2  NDESL and any Relevant Party shall not without the Seller's prior
              written consent assign the Britannia Contract (except for an
              assignment to another member of the Abbot Group if the assignment
              will not adversely affect the amount of or timing of payment of
              the Britannia Bonus) and shall not otherwise divest itself of any
              rights or obligations thereunder in either case during the period
              until the Buyer shall have complied with all of its obligations
              under Section 6.5.6 or until the Seller has been released from
              the guarantee of the Britannia Contract referred to in Part 1 of
              Schedule 9, whichever is later;

       6.5.3  no member of the Abbot Group shall initiate any action nor agree
              to any proposal whereby the terms of the Britannia Contract are
              amended or any other arrangements are entered into which is
              likely to adversely affect the amount of or the timing of payment
              of the Britannia Bonus save (i) with the Seller's written
              consent, which consent (or refusal to consent) shall not be
              unreasonably delayed or (ii) if the Seller has received at the
              date of any such action, amendment or other arrangement referred
              to in this Section 6.5.3, payment from the Buyer or from Abbot of
              a sum equal to the Estimated Bonus





                                       41
<PAGE>   42
              after deduction of a sum representing tax at the Notional Tax
              Rate and the Seller has at such date been released from the
              guarantee of the Britannia Contract referred to in Part 1 of
              Schedule 9;

       6.5.4  NDESL and any Relevant Party shall supply to the Seller
              immediately upon receipt a copy of the monthly cost reports
              prepared by the Independent Operator in connection with the
              Britannia Contract;

       6.5.5  NDESL and any Relevant Party shall use all reasonable endeavours
              to procure that payment of the Britannia Bonus is made by the
              Independent Operator strictly in accordance with the terms of the
              Britannia Contract as at the date hereof or as varied pursuant to
              Section 6.5.3 and in any event within 60 days of the due date
              therefor; and if there is any dispute with the Independent
              Operator as to the amount of the Britannia Bonus payable, neither
              NDESL or any Relevant Party nor any member of the Abbot Group
              shall seek to compromise or settle the amount of such bonus
              without the consent of the Seller; the Seller may at any time
              after the expiry of such 60 day period and shall, after it has
              refused to give its consent to any compromise or settlement, take
              over the conduct of such claim against the Independent Operator
              and the Buyer shall procure that NDESL or any Relevant Party
              shall take such action with respect to the conduct of such claim
              as the Seller shall reasonably request subject to the Seller
              indemnifying and keeping NDESL or any Relevant Party indemnified
              against all costs and expenses thereby incurred;

       6.5.6  not later than 7 days after receipt by NDESL or any Relevant
              Party or any member of the Abbot Group of the Britannia Bonus (or
              any part of it) the Buyer shall, subject to section 6.5.7, pay to





                                       42
<PAGE>   43
              the Seller the amount of such receipt in the currency received
              after deduction of a sum representing tax at the Notional Tax
              Rate.  Such payment shall be made by telegraphic transfer of
              immediately available funds into such bank account of the Seller
              as was specified pursuant to Section 2.2.1 or such other account
              as may previously have been notified in writing by the Seller to
              the Buyer;

       6.5.7  notwithstanding Section 6.5.6, the Buyer shall not be obliged to
              pay over any sums received by NDESL or any Relevant Party or any
              member of the Abbot Group or by any successor or assign of any of
              them by way of Britannia Bonus Account Payment until the date
              upon which such person receives payment of the Drilling
              Facilities Profit as finally determined at which time the Buyer
              shall pay over a sum equal to the Drilling Facilities Profit less
              the sum of all Britannia Bonus Account Payments received by NDESL
              or any Relevant Party prior to the Closing Date net of a sum
              representing tax at the Notional Tax Rate on the amount of such
              payment and such sums shall be treated for all purposes
              thereafter as if they were part of the Drilling Facilities Profit
              portion of the Britannia Bonus;

       6.5.8  interest shall be chargeable at the rate of 3% per annum over the
              base rate of National Westminster Bank plc compounded monthly on
              sums which are overdue under Section 6.5.6, from the due date for
              payment thereunder until the date of actual payment to the
              Seller.





                                       43
<PAGE>   44
6.6    CONTRACTS. The Seller agrees to indemnify the Buyer and keep the Buyer
       indemnified (for itself and as trustee for the benefit of each member of
       the Target Group) from and against all liabilities damages and costs
       arising out of or in connection with any claim or proceedings made
       (whether commenced before or after the date of this Agreement) against
       any member of the Target Group by any other party to any contract
       (including the Contracts) to which any member of the Target Group is or
       has at any time prior to the date of this Agreement been a party as a
       result of any breach prior to Closing by such member of the Target Group
       of any term of such contract (where such breach gives rise to a
       liability for a member of the Target Group in excess of L.50,000) and
       except to the extent that the Buyer has continued such breach after
       Closing, provided always that the liability of the Seller under this
       Section 6.6 shall be limited to the full amount of the claim made by the
       other party to such contract (including any damages awarded to such
       other party for lost profits or without limitation other consequential
       losses) and shall in no circumstances include any other damages, lost
       profits or, without limitation, other consequential losses of the Buyer
       or other member of the Target Group or the Abbot Group (other than the
       costs and expenses of the Buyer or other relevant member of the Target
       Group of defending such claim) resulting from the termination of such
       contract and provided further that the liability of the Seller shall be
       subject to the limitations referred to in Section 8 other than Section
       8.2.

7.     CONDITIONS TO OBLIGATION TO CLOSE.

7.1    CONDITIONS.  Closing shall be subject to the Buyer's rights under
       Section 5.4 and:

       7.1.1  the passing by Abbot's shareholders without amendment of the
              ordinary resolution and the special resolution set out in the





                                       44
<PAGE>   45
              notice of extraordinary general meeting attached to the Abbot
              Circular; and

       7.1.2  the admission to listing of the shares which are the subject of
              the placing and open offer described in the Abbot Circular on the
              London Stock Exchange becoming effective;

       7.1.3  the Seller having complied with its covenants hereunder to
              discharge intercompany and third party indebtedness, to procure
              transfer of the Excluded Assets out of the Target Group and to
              transfer the Drill Pipe and Equipment to NDESL all as more
              particularly detailed in Sections 5.5 to 5.8; and

7.2    The Buyer shall use all reasonable endeavours to procure fulfilment of
       the Condition set out in Sections 7.1.1 and 7.1.2 including without
       limitation making application to the London Stock Exchange not later
       than 14 November 1996 for the admission of the shares which are subject
       to the placing and open offer described in the Abbot Circular; and the
       Seller shall use all reasonable endeavours to procure fulfilment of the
       Condition set out in Section 7.1.3 in each case as soon as possible and
       shall notify the other immediately upon fulfilment of each such
       Condition.

7.3    If either the Buyer, Abbot or the Seller becomes aware of any matter,
       circumstance or thing that might prevent a Condition being satisfied it
       shall immediately notify the other.

7.4    The Buyer shall be entitled to waive the Condition (or any part of it)
       contained in Section 7.1.3 and the Seller shall be entitled to waive the
       Condition contained in Section 7.1.1 so far as it relates to the passing
       of the special resolution but not so far as it relates to the passing of
       the ordinary resolution.





                                       45
<PAGE>   46
8.     LIABILITY UNDER REPRESENTATIONS AND WARRANTIES. The provisions of this
       Section shall operate to limit the liability of the Seller in respect of
       any claim under or in connection with (i) the Warranties referred to in
       Section 4, (ii) Section 6.6 and (iii), except where expressly provided
       to the contrary, the Tax Covenant and references to "claim" and "claims"
       shall be construed accordingly.  The Parties agree as follows:

8.1    AGGREGATE LIABILITY. The maximum aggregate liability of the Seller in
       respect of all claims shall not exceed Pound Sterling 20,000,000;

8.2    SMALL CLAIMS. Except in relation to a claim in respect of Taxation,
       under the Tax Covenant or under Section 6.6 where no such limit applies,
       no liability shall attach to the Seller where the amount of any claim is
       less than Pound Sterling 20,000, such claims being ignored for the 
       purposes of calculating the liability of the Seller under this Agreement;

8.3    DEDUCTIBLE. Except in relation to a claim in respect of Taxation or
       under the Tax Covenant where no such limit applies, no liability shall
       attach to the Seller unless the aggregate amount of all claims for which
       it would, in the absence of this provision, be liable shall exceed
       Pound Sterling 500,000 and in such event the Seller shall only be 
       liable for the excess;

8.4    NOTIFICATION OF CLAIMS.  No claim shall be brought against the Seller
       unless:-

       8.4.1  written particulars thereof (stating in reasonable detail of
              which the Buyer is aware the specific matters in respect of which
              the claim is made) shall have been notified in writing to the
              Seller before in the case of a claim relating to Taxation or
              under the Tax Covenant 31 December 2003 or in relation to any
              other claim 31 March 1998; and





                                       46
<PAGE>   47
       8.4.2  in the case of a claim other than one relating to Taxation or
              under the Tax Covenant proceedings in respect of the claim shall
              have been commenced by being both issued and served within twelve
              months of the giving of such notice and in the case of a claim
              relating to Taxation or under the Tax Covenant proceedings in
              respect of the claim shall have been commenced by being both
              issued and served on or before 31 December 2004;

8.5    NOTIFICATION AS SOON AS PRACTICABLE.  No liability shall attach to the
       Seller in respect of any claim other than a claim relating to Taxation
       or under the Tax Covenant unless notice is given to the Seller of the
       relevant facts of that claim as soon as reasonably practicable and in
       any event no later than 90 days after the senior management of the Buyer
       or any member of Target Group becomes aware thereof provided that a
       failure to comply with this provision shall not prevent the Buyer
       recovering damages for any such claim to the extent it can show that the
       Seller has not been prejudiced by such failure;

8.6    THIRD PARTY CLAIMS.  In the event that a claim other than a claim under
       the Tax Covenant against the Seller arises as a result of or in
       connection with a liability to or a dispute with any third party, then,

       8.6.1  if the sum claimed is Pound Sterling 250,000 or more and if the 
              Seller notifies the Buyer in writing of its wish to have conduct
              of the liability or dispute with the third party, the Buyer shall
              (provided that it is indemnified and kept indemnified by the
              Seller against any costs and expenses which may be incurred by
              the Buyer in taking such action) take and shall procure that the
              relevant member of the Target Group shall take such action to
              avoid, dispute, resist, appeal, compromise or contest such
              liability or dispute as may be reasonably requested by the
              Seller;
        




                                       47
<PAGE>   48
       8.6.2  if the sum claimed is less than Pound Sterling 250,000, and/or 
              until the Seller has elected to have conduct of a given liability
              or dispute under Section 8.6.1, the Buyer shall be free to
              conduct such liability or dispute provided that no such liability
              or dispute shall be admitted, settled or discharged without the
              written consent of the Seller such consent (or refusal to
              consent) not to be unreasonably delayed;
        
       8.6.3  if the Seller shall have refused to give its consent to any
              admission, settlement or discharge, the Buyer may (i) elect to
              retain conduct of the liability or dispute in which event the
              Buyer shall be responsible for the whole amount of any subsequent
              settlement of or judgment in respect of such liability or dispute
              including any associated costs and expenses and shall not be
              entitled to recover all or any part thereof from the Seller or
              (ii) elect that the Seller take over exclusive conduct of the
              liability or dispute in which event the Seller shall be
              responsible for the whole amount of any subsequent settlement of
              or judgment in respect of such liability or dispute including any
              associated costs and expenses less any deductible which may be
              applicable pursuant to Section 8.4 for which the Buyer shall be
              responsible; and

       8.6.4  where the Seller has conduct of any liability or dispute in
              accordance with Sections 8.6.1 to 8.6.3, the Seller shall report
              to the Buyer at intervals of not less than once in a period of
              thirty days.

8.7    CLAIMS AGAINST THIRD PARTIES.  In the event that the Buyer or any member
       of the Target Group is entitled to recover any sum (whether by payment,
       discount, credit or otherwise) from any third party (including any
       Taxation Authority) in respect of any matter for which a claim other
       than a claim under the Tax Covenant could be made against the Seller,





                                       48
<PAGE>   49
       the Buyer shall provided that it is indemnified and kept indemnified by
       the Seller against any costs and expenses which may be incurred by the
       Buyer in relation to such recovery use, or procure that the relevant
       member of the Target Group shall use, all reasonable endeavours to
       recover such sum before making the claim against the Seller, and any sum
       recovered will reduce the amount of the claim (after deduction of all
       reasonable costs and expenses of recovery); and, in the event of the
       recovery being delayed until after the claim has been satisfied by the
       Seller, the Buyer shall account to the Seller in respect of any amount
       so recovered (after deduction of all reasonable costs and expenses of
       the recovery) up to the amount of the claim.  This Section 8.8 shall not
       apply to any entitlement to recover sums by way of Britannia Bonus from
       the Independent Operator, which shall be governed by Section 6.5.

8.8    GENERAL.  No liability shall attach to the Seller in respect of any
       claim other than a claim under the Tax Covenant:

       8.8.1  to the extent that provision or reserve in respect of the matter
              or thing giving rise to such claim has been provided for in the
              Financial Statements or that such matter or thing has been taken
              into account therein or in determining the amount of the
              Consolidated Working Capital;

       8.8.2  if such claim would not have arisen but for a change in the rate
              of Taxation or a change in legislation made after the date hereof
              with retrospective effect any extra statutory concession or
              practice previously made by any Taxation Authority (whether or
              not such change purports to be effective retrospectively in whole
              or in part) or if such claim would not have arisen but for any
              judgment delivered after the date hereof;

       8.8.3  to the extent that such claim would not have arisen but for a
              change in the treatment of assets and liabilities or of the





                                       49
<PAGE>   50
              Taxation attributable to timing differences (including capital
              allowances) in future accounts of the Target Group or but for any
              other change in the accounting bases upon which the Target Group
              prepares its future accounts except to the extent necessary to
              rectify any non compliance with GAAP as at the date of this
              Agreement;

       8.8.4  to the extent that such claim relates to any loss for which the
              Buyer or any member of the Target Group is indemnified by
              insurance;

       8.8.5  if and to the extent that such claim would not have arisen or
              would have been reduced or eliminated but for a failure on the
              part of any member of the Target Group to make any claim,
              election, surrender or disclaimer or give any notice or consent
              or do any other thing after Closing the making, giving or doing
              of which was taken into account in preparing the Financial
              Statements or determining the Consolidated Working Capital;

       8.8.6  to the extent that the claim or breach would not have arisen but
              for some act, omission, transaction or arrangement whatsoever
              carried out at the written request or with the written approval
              of the Buyer prior to Closing or which was expressly authorised
              by the Agreement.

8.9    USE OF RELIEFS.  Where and to the extent that there are available to the
       Target Group any reliefs, rights of repayment or other rights or claims
       of a similar nature to set against or otherwise mitigate any liability
       arising from any claim for Taxation giving rise to a claim under the
       Warranties or the Tax Covenant and such reliefs, rights of repayment or
       other rights or claims have not been taken into account in computing and
       so reducing or eliminating any provision for deferred Taxation or
       treated as an asset in the Consolidated Working Capital Statement





                                       50
<PAGE>   51
       wholly by reason of any act, omission or transaction of any member of
       the Target Group before the date of Closing, credit for any such
       reliefs, rights of repayment or other rights or claims shall be given to
       the Seller to the extent that they can be set off against the liability
       in question.

8.10   CESSER OF LIABILITY.  The liability of the Seller shall cease and any
       subsisting claim which relates to the business or assets of any member
       of the Target Group shall be withdrawn upon that member of the Target
       Group or its business or substantially all of its assets ceasing for any
       reason within the twelve months after the date of Closing to be directly
       or indirectly controlled by Abbot.

8.11   WARRANTIES EXCLUSIVE.  The Buyer, other than in relation to the
       representations and warranties contained in Sections 3.1 and 4, waives
       any remedies it may have under the Misrepresentation Act 1967 and any
       remedy it may have for breach of warranty in relation to any information
       (written or oral), statements or warranties or representations of any
       description made, supplied or given by the Seller or any member of the
       Retained Group or the Target Group or the officers, agents, employees or
       advisers of any of them in relation to the assets and liabilities of the
       Target Group, their value or amount, or the business or affairs of the
       Target Group.

8.12   WAIVER OF RESCISSION.  The Buyer shall not be entitled to rescind this
       Agreement in any circumstances other than as provided in Section 5.4.

8.13   REDUCTION OF CONSIDERATION.  If the Seller pays any sum to the Buyer
       pursuant to a claim, the Purchase Price shall be deemed to be reduced by
       the amount of such payment.





                                       51
<PAGE>   52
8.14   MITIGATION OF LOSS.  Nothing in this Section 8 shall limit or restrict
       the Buyer's general obligation at law to mitigate any loss or damage
       which it may incur in consequence of any matter giving rise to a
       potential claim under this Agreement.

8.15   BREACH OF THE CONTRACTS.  In addition to the other limitations set out
       in this Section 8, the liability of the Seller in respect of any claim
       by any member of the Abbot Group under or in connection with paragraphs
       8.1 and 8.3 of the Warranties in Schedule 8 shall be limited to the
       amount required to remedy the breach of the applicable law or to obtain
       the relevant Licence.

8.16   DOUBLE CLAIMS.  No claim shall be made under the Warranties in respect
       of any matter for which a claim has been made under Section 6.6 of this
       Agreement or under the Tax Covenant or vice versa.

9.     TERMINATION

9.1    TERMINATION OF AGREEMENT.  The Buyer and Seller may terminate this
       Agreement by mutual written consent at any time prior to the Closing.

9.2    EFFECT OF TERMINATION.  If any Party terminates this Agreement pursuant
       to Section 9.1, Section 2.5.3 and Section 5.4 all rights and obligations
       of the Parties hereunder shall terminate without any liability of any
       Party to any other Party; provided, however, that the confidentiality
       provisions contained in Section 12 and the provisions of Section 14
       (other than Sections 14.5, 14.9 and 14.13) shall survive termination and
       further provided that such termination shall be without prejudice to the
       rights of any Party to claim in respect of any breach of this Agreement
       by any other Party.





                                       52
<PAGE>   53
10.    TAX

10.1   In relation to Taxation the provisions of Schedule 7 shall apply.

10.2   Not later than 7 days after receipt by NDESL or any Relevant Party or
       any member of the Abbot Group of a Tax Refund received in connection
       with the litigation referred to in Section 6.2 the Buyer shall pay to
       the Seller a sum equal to the amount of the Tax Refund after deduction
       of any Liability for Taxation thereon of NDESL or any Relevant Party or
       any member of the Abbot Group related to such Tax Refund.  Such payment
       shall be made by telegraphic transfer of immediately available funds
       into such bank account of the Seller as was specified pursuant to
       Section 2.2.1 or such other account as may be nominated by the Seller.
       For the avoidance of doubt, if any Tax Refund is received by any member
       of the Retained Group, such member shall be entitled to retain the same
       and shall be entitled to set off the obligation of the Buyer pursuant to
       this Section 10.2 against any obligation of Loffland Brothers North Sea,
       Inc to make payment of any Tax Refund to NDESL pursuant to the agreement
       between Loffland Brothers North Sea, Inc and NDESL dated 21 September
       1990.

10.3   If after any payment is made pursuant to Section 10.2 and the receipt by
       NDESL or any Relevant Party or any member of the Abbot Group of the
       relevant Tax Refund gives rise to a Liability for Taxation of NDESL or
       any Relevant Party or any member of the Abbot Group then (if and to the
       extent that the amount of the Liability for Taxation was not deducted
       from the payment made by the Buyer pursuant to Section 10.2) the Seller
       shall pay to the Buyer (by way of refund of any amount paid pursuant to
       Section 10.2) an amount (which is after taking into account any Taxation
       payable on such amount) equal to such Liability for Taxation such
       payment to be made five days after the Buyer shall serve notice on the
       Seller demanding payment.





                                       53
<PAGE>   54
11.    PROTECTION OF GOODWILL.

11.1   The Seller undertakes to the Buyer that, without the written consent of
       the Buyer:-

       11.1.1 in respect of any and all fixed platforms located in the United
              Kingdom Continental Shelf, for a period of 3 years from Closing
              it will not and will procure that no other member of the Retained
              Group shall directly or indirectly and whether as principal,
              agent, shareholder or partner, enter into or offer to enter into
              any agreement for the provision of (i) labour only services of
              substantially the same type and for substantially the same
              purposes as those services presently provided by members of the
              Target Group pursuant to the Contracts or (ii) the services of
              managing platform drilling crews, maintaining platform drilling
              equipment and providing engineering services relating to drilling
              facilities; and

       11.1.2 it will not and will procure that no other member of the Retained
              Group will directly or indirectly and whether as principal,
              agent, shareholder or partner, for a period of 2 years from
              Closing offer employment to any person who is at the date of this
              Agreement and/or was at Closing an employee employed in a
              managerial, technical or sales capacity by any member of the
              Target Group nor do any act or thing intended to cause any such
              employee to terminate his employment with any member of the
              Target Group, whether or not such employee would thereby breach
              his contract of employment.

11.2   Nothing in Section 11.1 shall prevent the Seller or any member of the
       Retained Group from acquiring any company or business or acquiring an
       interest in such company or business whether as principal, agent,





                                       54
<PAGE>   55
       shareholder or partner where part of such business ("the Competing
       Part") comprises the provision of labour services or Relevant Services
       of the type and in the geographic area referred to in Section 11.1,
       provided:

              (i)       that such Competing Part does not comprise a majority
                        (calculated by reference to its profits on ordinary
                        activities before Taxation) of the business acquired;
                        and

              (ii)      that, to the extent the Seller or any member of the
                        Retained Group acquires operating control of the
                        Competing Part, it shall exercise its right of control
                        to procure that the Competing Part does not offer to
                        provide (for the period and in the geographic area
                        referred to in Section 11.1) labour services or
                        Relevant Services of the type referred to in Section
                        11.1 the result of which would be the loss of a
                        contract pursuant to which any member of the Abbot
                        Group is providing at the date of such acquisition
                        substantially the same services provided pursuant to
                        any other contracts to which any member of the Abbot
                        Group may at the date of such acquisition be party.

11.3   The Buyer hereby agrees with the Seller that for the period of 3 years
       from Closing neither the Buyer nor any member of the Abbot Group shall
       offer to provide (for the period and in the geographic area referred to
       in Section 11.1) labour services or Relevant Services of the type
       referred to in Section 11.1 the result of which would be the loss of a
       contract pursuant to which the Competing Part is providing at the date
       of such acquisition substantially the same services.

11.4   Nothing in Section 11.1.2 shall prevent the Seller or any member of the
       Retained Group from offering employment to any of the employees





                                       55
<PAGE>   56
       listed in Part 1 of Schedule 4 (i) at any time after the expiry of six
       months from Closing if they shall by that time have been or at any time
       thereafter are, made redundant or (ii) at any time prior to Closing.

11.5   Each of the undertakings contained in Section 11.1 is separate and
       severable and shall be construed on that basis.  If any of such
       undertakings is found to be void but would be valid if some part of it
       were deleted or if the period or extent of it were reduced such
       undertaking shall apply with such modification as may be necessary to
       make it valid and effective.

11.6   For the avoidance of doubt, the provisions of Section 11 shall not
       extend (i) to any activities carried out by the Seller or any other
       member of the Retained Group in respect of the Excluded Assets; nor (ii)
       to any supply or offer to supply labour services in connection with the
       sale, supply, leasing or other provision of any rig which uses the
       "Sundowner" technology.

11.7   If Closing of this transaction shall not occur on or before 21 November
       1996, Abbot shall not and shall procure that no member of the Abbot
       Group shall for a period of three years following the date of this
       Agreement provide services to those persons who are currently
       independent operators under the Contracts or wireline contracts of a
       type which are provided under the Contracts or wireline contracts as at
       the date of this Agreement in respect of the platforms to which those
       Contracts relate.  This Section 11.7 shall cease to apply upon the
       Seller ceasing to own a majority of the ordinary shares of NDESL or if,
       in respect of any given Contract, such Contract is terminated and NDESL
       is not permitted to tender for the renewal or extension of the Contract
       in question.





                                       56
<PAGE>   57
12.    CONFIDENTIAL INFORMATION

12.1   The Seller shall before and after Closing not make use of or disclose to
       any person Confidential Information belonging to the Target Group, take
       all reasonable steps to prevent the use or disclosure by any member of
       the Retained Group of Confidential Information belonging to and/or used
       by the Target Group and procure that each member of the Retained Group
       complies with the provisions of this Section 12.

12.2   Section 12.1 does not apply to use or disclosure of Confidential
       Information required to be used or disclosed by law, a court of
       competent jurisdiction or by the London Stock Exchange or any exchange
       on which the Seller's shares are traded or to the disclosure of
       Confidential Information to a director, officer or employee of the Buyer
       or to an employee of the Target Group whose function requires that he
       has possession of the Confidential Information or disclosure of
       Confidential Information to an adviser for the purposes of advising the
       Seller in connection with this Agreement or Confidential Information
       which becomes publicly known except as a result of the Seller's breach
       of Section 12.1.

12.3   Section 12.1 does not apply to the use or disclosure of Confidential
       Information belonging to and for use by the Target Group in respect of
       or in any way connected with the Excluded Assets or in any way connected
       with Sundowner or Canrig technology.

12.4   Abbot covenants not to make use of or disclose and to take all
       reasonable steps to prevent the use or disclosure by any member of the
       Abbot Group of any Sundowner or Canrig technology or information
       relating thereto which it may have in its possession.





                                       57
<PAGE>   58
13.    GUARANTEE

13.1   In consideration of the Seller entering into this Agreement, Abbot
       hereby unconditionally and irrevocably guarantees to the Seller the due
       and punctual performance and observance by the Buyer of its obligations,
       undertakings, warranties, indemnities and covenants under or pursuant to
       this Agreement and the Ancillary Documents and agrees to indemnify and
       keep indemnified the Seller against all losses, damages, costs and
       expenses (including legal costs and expenses) which the Seller may
       suffer through or arising from any breach by the Buyer of such
       obligations, warranties, undertakings, indemnities or covenants.  The
       liability of Abbot as aforesaid shall not be released or diminished by
       any arrangements or alterations of terms (whether of this Agreement or
       the Ancillary Documents or otherwise) or any forbearance, neglect or
       delay in seeking performance of the obligations hereby imposed or any
       granting of time for such performance.

13.2   If and whenever the Buyer defaults for any reason whatsoever in the
       performance of any obligation or liability undertaken or expressed to be
       undertaken by it under or pursuant to this Agreement or the Ancillary
       Documents, Abbot shall forthwith upon demand unconditionally perform (or
       procure performance of) and satisfy (or procure the satisfaction of) the
       obligation or liability in regard to which such default has been made in
       the manner prescribed by this Agreement or the Ancillary Documents (as
       the case may be) and so that the same benefits shall be conferred on the
       Seller or any member of the Retained Group as it would have received if
       such obligation or liability had been duly performed and satisfied by
       the Buyer.  Abbot hereby waives any rights which it may have to require
       the Seller to proceed first against or claim payment from the Buyer to
       the intent that as between the Seller and Abbot the latter shall be
       liable as principal debtor as if it had entered





                                       58
<PAGE>   59
       into all undertakings, agreements and other obligations jointly and
       severally with the Buyer.

13.3   This guarantee and indemnity is to be a continuing security to the
       Seller for all obligations, warranties, undertakings, indemnities and
       covenants on the part of the Buyer under or pursuant to this Agreement
       and the Ancillary Documents notwithstanding any settlement of account or
       other matter or thing whatsoever.

13.4   This guarantee and indemnity is in addition to and without prejudice to
       and not in substitution for any rights or security which the Seller may
       now or hereafter have or hold for the performance and observance of the
       obligations, undertakings, covenants, indemnities and warranties of the
       Buyer under or in connection with this Agreement or the Ancillary
       Documents.

13.5   In the event of Abbot having taken or taking any security from the Buyer
       in connection with this guarantee and indemnity, Abbot hereby undertakes
       to hold the same in trust for the Seller pending discharge in full of
       all Abbot's obligations under this Agreement and the Ancillary
       Documents.  Abbot shall not, after any claim has been made pursuant to
       this Section 13, claim from the Buyer any sums which may be owing to it
       from the Buyer or have the benefit of any set-off or counter-claim or
       proof against or dividend, composition or payment by the Buyer until all
       sums owing to the Seller in respect hereof shall have been paid in full.

13.6   As a separate and independent stipulation, Abbot agrees that any
       obligation expressed to be undertaken by the Buyer under this Agreement
       or the Ancillary Documents (including, without limitation, any moneys
       expressed to be payable under this Agreement) which may not be
       enforceable against or recoverable from the Buyer by reason of any legal
       limitation, disability or incapacity of any of them or any other fact or
       circumstance shall nevertheless be enforceable against or





                                       59
<PAGE>   60
       recoverable from Abbot as though the same had been incurred by Abbot and
       Abbot were sole or principal obligor in respect thereof and shall be
       performed or paid by Abbot on demand.

14.    MISCELLANEOUS

14.1   PRESS RELEASES AND PUBLIC ANNOUNCEMENTS.  No Party shall issue any press
       release or make any public announcement relating to the subject matter
       of this Agreement without the prior written approval of the others;
       provided, however, that any Party may make any public disclosure if
       required by applicable law, a court of competent jurisdiction, the
       London Stock Exchange, the Securities and Exchange Commission or any
       listing or trading agreement concerning its publicly-traded securities
       (in which case the disclosing Party will, where practicable, use its
       reasonable endeavours to advise and consult with the other Party as to
       the contents prior to making the disclosure.  This shall not apply to
       announcements made or sent by the Buyer after Closing advising
       customers, suppliers and others who have dealings with the Target Group
       of the change in control of the Target Group.

14.2   NO THIRD-PARTY BENEFICIARIES. This Agreement shall not confer any rights
       or remedies upon any Person other than the Parties and their respective
       successors and permitted assigns.

14.3   ENTIRE AGREEMENT.  This Agreement (including the Ancillary Documents)
       constitutes the entire agreement among the Parties and supersedes any
       prior understandings, agreements, or representations by or among the
       Parties, written or oral, to the extent they have related in any way to
       the subject matter hereof.

14.4   SUCCESSION AND ASSIGNMENT.  This Agreement shall be binding upon and
       inure to the benefit of the Parties named herein and their respective
       successors and permitted assigns.  No Party may assign either this





                                       60
<PAGE>   61
       Agreement or any of its rights, interests, or obligations hereunder
       without the prior written approval of the other Parties except, after
       Closing, to any wholly-owned subsidiary.  No such assignment shall
       relieve the assignor of any obligations under this Agreement.

14.5   COUNTERPARTS. This Agreement may be executed in one or more
       counterparts, each of which shall be deemed an original but all of which
       together will constitute one and the same instrument.

14.6   HEADINGS. The section headings contained in this Agreement are inserted
       for convenience only and shall not affect in any way the meaning or
       interpretation of this Agreement.

14.7   NOTICES. All notices, requests, demands, claims, and other
       communications hereunder ("notices") will be in writing. Any notice
       hereunder shall be deemed duly given if delivered personally at the
       address shown below or if it is sent by first class recorded delivery
       post or certified airmail, postage prepaid, and addressed to the
       intended recipient as set forth below:


       If to the Seller: Nabors Industries Inc.   Copy to: Baker & McKenzie
                         515 West Greens Road              100 New Bridge Street
                         Suite 1200                        London  EC4V 6JA
                         Houston
                         Attention: President              Attention: HS/SCH/APD

       If to the Buyer:  KCA Drilling Group       Copy to: Pinsent Curtis
                         Limited                           Dashwood House
                         Minto Drive, Altens               69 Old Broad Street
                         Aberdeen  AB12 3LW                London
                         Attention: Company Secretary      Attention: AF/CP





                                       61
<PAGE>   62

       If to Abbot:      Abbot Group Plc          Copy to: Pinsent Curtis
                         Minto Drive                       Dashwood House
                         Altens                            69 Old Broad Street
                         Aberdeen  AB12 3LW                London
                         Attention: Company Secretary      Attention: AF/CP


       A Party may change the address to which notices are to be delivered by
       giving the other Parties notice in the manner herein set forth.  Any
       notice delivered personally, shall be deemed served at the time of
       delivery, if delivered by recorded delivery other than airmail two days
       after posting and if sent by airmail five days after posting or if such
       day is not a Business Day then the next following Business Day.

14.8   GOVERNING LAW. This Agreement shall be governed by and construed in
       accordance with the laws of England without giving effect to any choice
       or conflict of law provision or rule whether of England or any other
       jurisdiction that would cause the application of the laws of any
       jurisdiction other than England and the Parties hereto submit to the
       non-exclusive jurisdiction of the English courts.  The Seller hereby
       agrees that service of any legal proceedings may be made on it by
       delivering them to the London office of its solicitors, Baker & McKenzie
       and the Buyer and Abbot each hereby agree that service of any legal
       proceedings may be made on it by delivering them to its solicitors,
       Pinsent Curtis.

14.9   AMENDMENTS.  No amendment of any provision of this Agreement shall be
       valid unless the same shall be in writing and signed by the Parties.

14.10  WAIVER.  The failure by any Party to exercise or delay in exercising any
       right or remedy under this Agreement shall not constitute a waiver of
       the right or remedy or a waiver of any other rights or remedies that
       Party may otherwise have and no single or partial exercise of any right





                                       62
<PAGE>   63
       or remedy under this Agreement shall prevent any further exercise of the
       right or remedy or the exercise of any other right or remedy.

14.11  SEVERABILITY.  Any term or provision of this Agreement that is invalid
       or unenforceable in any situation in any jurisdiction shall not affect
       the validity or enforceability of the remaining terms and provisions
       hereof or the validity or enforceability of the offending term or
       provision in any other situation or in any other jurisdiction.

       14.12    EXPENSES  

       14.12.1  Subject to the remainder of this Section 14, each of
                the Buyer, Abbot and the Seller will bear its own costs and
                expenses (including legal fees and expenses) incurred in
                connection with this Agreement and the transaction contemplated
                hereby.

       14.12.2  If Closing does not occur on or before 21 November 1996
                otherwise than as a result of the Buyer lawfully exercising its
                right to rescind this Agreement pursuant to Section 5.4.1, the
                Seller shall have the following remedies:

                14.12.2.1  Abbot shall forthwith upon the expiry of such period
                           pay to the Seller the sum of L.1,000,000 being a sum
                           agreed between the parties as representing
                           compensation for the costs, expenses and management
                           time that has been incurred by the Seller and its
                           Affiliates in relation to the proposed sale of the
                           Company Shares.  By way of security for the
                           liability of the Buyer under this Section 14.12.2.1,
                           the Buyer shall at the date of this Agreement pay
                           the sum of L.1,000,000 into a separately designated
                           interest-bearing deposit account with National
                           Westminster Bank Plc (the "Escrow Account") which
                           account shall be free from any lien,





                                       63
<PAGE>   64
                           charge, encumbrance, set-off or counterclaim and
                           which shall be operated as provided in Schedule 11.

                14.12.2.2  From the outset of the negotiations leading to this
                           Agreement, the parties have agreed that if this
                           Agreement could not be executed and the transaction
                           closed on essentially a simultaneous basis, then one
                           of the risks of the transaction's failure to close,
                           specifically the risk of loss of profit as a
                           consequence of any termination of a Contract,
                           regardless of the cause of such termination would be
                           borne by Abbot and the Buyer.

                           The parties understand that as a consequence of the
                           requirement for Abbot to obtain the approval of its
                           shareholders for such transaction pursuant to the
                           Listing Rules of the London Stock Exchange a
                           simultaneous execution and closing is not possible.
                           Accordingly, without prejudice to and in addition to
                           the Seller's rights under Section 14.12.2.1 and
                           14.12.2.3, if, after signing of this Agreement, a
                           Contract is terminated (otherwise than by a member
                           of the Target Group or its successors or assigns) or
                           a notice of termination of a Contract is sent to any
                           member of the Target Group or its successors or
                           assigns, then Abbot and the Buyer will be jointly
                           and severally liable for all losses, damages, costs
                           and expenses suffered by the Seller in connection
                           with such termination including without limitation,
                           lost profits for what would have been the remainder
                           of the principal term of the Contract had it not
                           been terminated.





                                       64
<PAGE>   65
                14.12.2.3  Without prejudice to, and in addition to the
                           Seller's rights under Sections 14.12.2.1 and
                           14.12.2.2, the Seller reserves its rights to claim
                           all losses, damage, costs and expenses suffered by
                           the Seller or any member of the Target Group
                           resulting from the inability to consummate the
                           execution and Closing of the sale of the Company
                           Shares on a simultaneous basis.

                14.12.2.4  The remedies specified in Sections 14.12.2.1 to
                           14.12.2.3 shall be without prejudice to any other
                           remedies the Seller may have resulting from a breach
                           by the Buyer or Abbot of this Agreement.

14.13  RTPA.  No party shall give effect to or enforce any restrictions
       contained in this Agreement or any agreement or arrangement of which
       this Agreement forms part and by virtue of which particulars of this
       Agreement (or the relevant agreement or arrangement) are required to be
       furnished under the RTPA until particulars have been duly furnished to
       the Director General of Fair Trading as required by the RTPA.





                                       65
<PAGE>   66
                                   SCHEDULE 1
                                COMPANY DETAILS

Part 1 - Nabors Europe Limited

Registered number:          1189464
Registered office:          Plumtree Court, London EC4A 4HT
Authorised share capital:   Pound Sterling 200 divided into 200 Ordinary 
                            Shares of Pound Sterling 1 each
Issued share capital:       Pound Sterling 102 divided into 102 Ordinary 
                            Shares of Pound Sterling 1 each
Shareholders:               Nabors Industries Inc - 101 Ordinary Shares of
                            Pound Sterling 1 each P&W Trustees (Aberdeen) 
                            Ltd - 1 Ordinary Share of Pound Sterling 1
Accounting Reference Date:  30 September
Directors:                  Garry Robert Allan
                            Larry Philip Heidt
                            Angus Petrie
Secretary:                  Garry Robert Allan

Part 2 Nabors Drilling and Energy Services (UK) Limited

Registered number:          SC125584
Registered office:          Kirkton Avenue
                            Pitmedden Road Industrial Estate
                            Aberdeen, Grampian AB2 0DP
Authorised share capital:   Pound Sterling 4,217,002 divided into 4,217,002 
                            Ordinary Shares of Pound Sterling 1 each
Issued share capital:       Pound Sterling 4,216,904 divided into 4,216,904 
                            Ordinary Shares of Pound Sterling 1 each
Shareholders:               Nabors Europe Limited - 4,216,903 Ordinary Shares
                            of Pound Sterling 1 each





                                       66
<PAGE>   67
                            P&W Trustees (Aberdeen) Limited - 1 Ordinary Share
                            of Pound Sterling 1
Accounting Reference Date:  30 September
Directors:                  Garry Robert Allan
                            Joseph Bruce
                            Larry Philip Heidt
                            Ewan Angus McLeod
                            Ernest Winston Simpson Nelson
                            Angus Petrie
Secretary:                  Garry Robert Allan

Part 3 - Thistle Well Services Limited

Registered number:          SC138344
Registered office:          Kirkton Avenue
                            Pitmedden Road Industrial Estate
                            Aberdeen, Grampian AB2 0DP7
Authorised share capital:   Pound Sterling 100,000 divided into 100,000 
                            Ordinary Shares of Pound Sterling 1 each
Issued share capital:       Pound Sterling 100,000 divided into 100,000 
                            Ordinary Shares of Pound Sterling 1 each
Shareholders:               Nabors Drilling and Energy Services (UK) Limited
                            99,999 Ordinary Shares of Pound Sterling 1 each 
                            P&W Trustees (Aberdeen) Limited - 1 Ordinary Share 
                            of Pound Sterling 1
Accounting Reference Date:  30 September
Directors:                  Garry Robert Allan
                            Larry Philip Heidt
                            Ewan Angus McLeod
                            Angus Petrie
Secretary:                  Garry Robert Allan





                                       67
<PAGE>   68
                                   SCHEDULE 2
         CONSOLIDATED WORKING CAPITAL STATEMENT - ACCOUNTING PRINCIPLES

The Working Capital Statement shall be prepared on the following basis:-

1.     GENERAL REQUIREMENTS

       (a)    as if the period from 30 September 1995 to the Closing Date were
              a financial period of the Target Group;

       (b)    in accordance with the requirements of all relevant statutes and
              generally accepted accounting principles and practices in the
              United Kingdom.

2.     SPECIFIC REQUIREMENTS

       (a)    TAX

              including full provision for Taxation (including deferred tax) up
              to and including the Closing Date and for the avoidance of doubt
              shall include corporation tax due, if any, as a result of (i) the
              transfer of Excluded Assets as detailed in Section 5.6 (ii) the
              repayment or discharge of indebtedness due to any bank or
              financial institution as detailed in Section 5.5 (iii) the
              cancellation or discharge or the intercompany loan account and
              all accounts due to HM Customs and Excise in respect of their
              enquiry into breaches of rules of the Company's IPR System, as
              detailed in the Disclosure Letter;





                                       68
<PAGE>   69
       (b)    PROVISION FOR EMPLOYEES

              including full provision to the extent required by GAAP for
              redundancy and all other employees costs engaged on the Elf and
              Oryx Contracts.

       (c)    STOCK

              Stocks are stated at the lower of cost and net realisable value.
              In general cost is calculated on an average cost basis.  Net
              realisable value is calculated by reference to the estimated
              selling prices less cost of realisation.

              Provision is made for obsolescent and slow moving stocks against
              specific stock items identified by management of the company,
              when the stock is considered to be of nil operational value.

       (d)    DEBTORS

              Sales regarding labour are recognised in accordance with terms of
              contracts.  Sales regarding equipment hire are recognised on a
              daily basis.

              Incentive well profit is recognised in the month in which the
              well is determined to have been completed.

              Foreign currency sales are translated at the average rate ruling
              in the month of the work being carried out.

              Trade debtors are stated at their invoice value after any
              provision for bad or doubtful debts.  A debtor is considered
              receivable on the earliest date on which payment is due, rather
              than on the earliest date on which payment is expected.





                                       69
<PAGE>   70
              Provision for bad debts is considered after a monthly review of
              the aged debt report.  Where customers have become insolvent or
              in liquidation provision is made in full.  When payment is
              overdue management adopt standard credit control procedures.
              When these procedures are exhausted full provision is made.

              Intercompany balances representing transactions with group
              companies are reconciled and agreed on a monthly basis.

              Prepayments are calculated on a time apportionment basis by
              amounts paid pre year end which relate to post year end.

              Accrued income includes work that has been carried out pre year
              end, but for which a sales invoice has not been raised by the
              year end.

       (e)    CASH AT BANK AND IN HAND

              Cash at bank and in hand includes cash in hand and deposits
              denominated in foreign currencies translated into sterling at the
              period end rate of exchange.  Deposits are included where they
              are repayable on demand with any bank.

       (f)    CREDITORS: AMOUNTS FALLING DUE WITHIN ONE YEAR

              Liabilities are recognised when the goods or services have been
              received.

              Trade creditors represent amounts owed to suppliers of goods and
              services which have been approved for payment and processed
              through the purchase ledger for payment.





                                       70
<PAGE>   71
              Loan creditor relates to the amount that is repayable within one
              year.

              Corporation tax creditor relates to the tax charge for the year,
              and any prior years that have not yet been paid.

              PAYE and social security creditor relates to the liability for
              the last month of the year to be paid the following month.  Also
              any other PAYE and National Insurance liabilities that have not
              been paid.

              Accruals represent the costs of goods received or services
              provided where these have not been processed through the purchase
              ledger.





                                       71
<PAGE>   72
                                   SCHEDULE 3
                                   CONTRACTS

(1)    Contract BRT1 - XA1 - Detail Design of Drilling Facilities and Drilling
       Operations and Maintenance.

       Parties:  Chevron U.K. Limited (1)
                 Nabors Drilling & Energy Services U.K. Limited (2)

       Date:     1 November 1994

       As amended by Amendment numbers 1 to 4 to Contract No. BRT1 XA1 dated 1
       November 1994, 1 April 1995, 1 September 1995 and 11 March 1996
       respectively.  (Refer to paragraph 11.1 of Schedule 8)

(2)    Contract ALB-1038 - Alba Field Development Northern Platform.

       Parties:  Chevron U.K. Limited (1)
                 Loffland Nabors U.K. Limited (now NDESL) (2)

       Date:     28 October 1991

       As amended by Amendment numbers 1 to 4 and 6 to 8 to Contract ALB - 1038
       dated 5 March 1992, 23 November 1992, 22 February 1993, September 1993,
       1 September 1994, 22 November 1994 and 1 October 1994 respectively.
       (Refer to paragraph 11.1 of Schedule 8)


(3)    Contract CNS-7174 - Integrated Drilling Services and Well Services -
       Ninian Field Operations.

       Parties:  Chevron U.K. Limited (1)
                 Nabors Drilling & Energy Services U.K. Limited (2)

       Date:     1 January 1994





                                       72
<PAGE>   73
       As amended by Amendment numbers 1 to 3 to Contract CNS - 7174 dated 22
       November 1994, 1 January 1995 and 1 July 1995 respectively.  (Refer to
       paragraph 11.1 of Schedule 8)

(4)    Contract W038 - Drilling, Well Intervention and Rig Maintenance Services
       on the Hutton and Murchison Platforms.

       Parties:  Oryx U.K. Energy Company (1)
                 Nabors Drilling & Energy Services U.K. Limited (2)

       Date:     23 February 1995

(5)    Contract C.A. 7400 - Provision of Platform Drilling Services.

       Parties:  Elf Enterprise Caledonia Ltd. (1)
                 Nabors Drilling & Energy Services U.K. Limited (2)

       Date:     15 July 1995

       As amended by Amendment number 1 to Contract CA. 7400 dated 24 April
       1996.  The letter referred to at Document 7.1/a/3/2 constitutes a de
       facto amendment to Contract CA. 7400. (Refer to paragraph 11.1 of
       Schedule 8)





                                       73
<PAGE>   74
                                   SCHEDULE 4
                          PART 1 - EXCLUDED EMPLOYEES

L. Heidt
E. Nelson
J. Bruce
C. Simpson
R. Morrison

              PART  2 - EMPLOYEES INCLUDED IN REDUNDANCY ADJUSTMENT

<TABLE>
<CAPTION>
NAME                                                                       TOTAL
<S>                                                                    <C>
Janet Ogg                                                              12,175,05
Shaun Huo                                                               4,781.50
Fiona Hay                                                               2,521.75
Else Salem                                                              1,927.22
Charlie Kidd                                                            5,090.67
Charlie Kidd                                                           11,000.00
Donna Cook                                                              1,507.57
Dan Wilton                                                              7,386.98
Calum Macdonald                                                         3,904.80
Laura Cameron                                                             752.56
Ian Penman                                                             10,968.26
Alistair Currie                                                         4,779.11
Stuart Souter                                                           1,428.56
Jimmy White                                                            20,000.00

TOTALS                                                                 88,224.03
</TABLE>





                                       74
<PAGE>   75
                                   SCHEDULE 5
                                EXCLUDED ASSETS

Part 1 - Residential Property:

a)     Dwellinghouse located at 5 Milltimber
       Brae East, Milltimber, Aberdeen

b)     Dwellinghouse located at 134 Deeside
       Gardens, Aberdeen

Part II - Assets assigned to US Branch:

The drilling rigs identified below together with pipe and all related assets
and supplies located and supplied in the USA including receivables and trade
payables:

(i)    Drilling Rig No. 518, a Gardner Denver
       1500.-E, located in the United States.

(ii)   Drilling Rig No. 90, a National 100-UE,
       located in the United States.

(iii)  Drilling Rig No. 93, a Gardner Denver
       1320-UE, located in the United States.

(iv)   Drilling Rig No. 273, a National 1320-
       UE, located in the United States.

Part III - Bids, tenders, proposals and information of a like nature relating
to:

(i)    The activities of Sundowner and its
       technology.





                                       75
<PAGE>   76
(ii)   The activities of Canrig and its
       technology.

(iii)  BHP Prirazlomnoye Project.

(iv)   Texaco Mariner Project.

(v)    All other bids, tenders and proposals
       and related working papers prepared by
       the Target Group, or any of them, which
       have not resulted in a contract being
       awarded to the Target Group, or any of
       them, and whose validity has expired by
       reason of the passing of time.


Part IV - Paloak Shares

99,900 shares of L.1 each in Paloak Limited

The Gleneagles Oilman's (AOGA) Sponsorship





                                       76
<PAGE>   77
                                   SCHEDULE 6
                                   PROPERTIES

1.     Lease of Main Building - sites 15 & 23 Kirkton Avenue Pitmedden Road
       Industrial Estate, Dyce, Aberdeen.

       Date:     21 October 1981 and 9 November 1981

       Parties:  Kabell (Management and Development) Limited (1)
                 Loffland Brothers North Sea Inc. (2)

2.     Lease of Site 19 Pitmedden Road Industrial Estate, Dyce, Aberdeen.

       Date:     10 January 1992 and 5 February 1992

       Parties:  The Grampian Regional Council (1)
                 Loffland Nabors U.K. Limited (2)

3.     Lease of sites 21 & 22 Pitmedden Road Industrial Estate, Dyce, Aberdeen

       Date:     25 November 1991 and 23 December 1991

       Parties:  The Grampian Regional Council (1)
                 Loffland Nabors U.K. Limited (2)

4.     Lease of Unit 6, International Base, Greenwell Road, East Tullos,
       Aberdeen.

       Date:     26 June 1992 and 6 July 1992

       Parties:  Citygate Court Property Limited (1)
                 Thistle Well Services Limited (2)





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<PAGE>   78
5.     Lease of Units 7 and 8 and Office Suites 1 and 4, International Base,
       Greenwell Road, East Tullos, Aberdeen.

       Date:     4 August 1989 and 19 August 1989

       Parties:  Scarborough and Aberdeen Property Company Limited (1)
                 Thistle Well Services Limited (2)

6.     Lease of Unit 2, International Base, Greenwell Road, East Tullos,
       Aberdeen.

       Date:     24 May 1981 and 14 June 1981
       Parties:  Citygate Court Property Company Limited (1)
                 Thistle Well Services Limited (2)

7.     Office Suite 6, International Base, Greenwell Road, East Tullos,
       Aberdeen

       Date:     26 June 1992 and 6 July 1992

       Parties:  Citygate Court Property Company Limited (1)
                 Thistle Well Services Limited (2)





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<PAGE>   79
       LIST OF DOCUMENTS RELATING TO THE PROPERTIES TO BE DELIVERED TO THE
       BUYER AT CLOSING

(a)    UNIT 2, INTERNATIONAL BASE, GREENWELL ROAD, EAST TULLOS INDUSTRIAL
       ESTATE, ABERDEEN

1.     Extract registered Lease between Citygate Court Property Co Ltd and
       Thistle Well Services Ltd registered 12th July 1991.

2.     Extract registered Assignation by Thistle Well Services Ltd in favour of
       Coldeal Ltd registered 18th February 1993.

3.     Copy Sub-Lease between Thistle Well Services Ltd and Nodeco Ltd dated
       28th May and 22nd August 1996.

4.     Letter of Consent dated 14th May 1996 from Landlord to the sub-lease
       between Thistle Well Services Ltd and Nodeco Ltd, with Thistle Well
       Services Ltd's acceptance.

5.     Correspondence relating to installation of crane and testing chamber
       comprising letter from City of Aberdeen Planning Department dated 8th
       November 1989 and letter from Ashley Property Consultants dated 14th
       November 1989.

6.     Copy planning permission dated 7th June 1995 relating to construction of
       unit loading canopy over door opening.

7.     Copy planning permission dated 27th September 1995 relating to proposed
       toilets and changing room.

8.     Copy building warrant B95/1448.

9.     Copy building warrant B95/1449.





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<PAGE>   80
10.    Copy executed an Assignation by Thistle Well Services Ltd in favour of
       Nabors Drilling and Energy Services (UK) Ltd with consent of Citygate
       Court Property Co Ltd dated 16 September 1996 and 8 October 1996.

(b)    UNIT 6, INTERNATIONAL BASE, GREENWELL ROAD, EAST TULLOS INDUSTRIAL
       ESTATE, ABERDEEN

1.     Extract registered Lease between Citygate Court Property Co Ltd and
       Thistle Well Services Ltd, registered 10th August 1992,

2.     Extract registered Assignation by Thistle Well Services Ltd in favour of
       Coldeal Ltd, registered 18th February 1993.

3.     Copy offer of sub-lease by Paull & Williamsons on behalf of Nabors
       Drilling and Energy Services (UK) Ltd to Oil Tech Trading Ltd.

4.     Copy executed an Assignation by Thistle Well Services Ltd in favour of
       Nabors Drilling and Energy Services (UK) Ltd with consent of Citygate
       Court Property Co Ltd dated 16 September 1996 and 8 October 1996.

(c)    UNITS 7 & 8 AND OFFICE SUITES 1 & 4, INTERNATIONAL BASE, GREENWELL ROAD,
       EAST TULLOS INDUSTRIAL ESTATE, ABERDEEN

1.     Extract registered Lease between Scarborough & Aberdeen Property Co Ltd
       and Thistle Well Services Ltd registered 5th September 1989.

2.     Extract registered Minute of Agreement recording a review of rent
       between Citygate Court Property Co Ltd and Thistle Well Services Ltd
       registered 2Oth September 1991.





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<PAGE>   81
3.     Extract registered Assignation by Thistle Well Services Ltd in favour of
       Coldeal Ltd registered 18th February 1993.

4.     Copy building warrant B92/1589 with copy completion certificate dated
       14th July 1992 relating thereto (alterations to office suites 1 & 4).

5.     Letter of Consent from Ashley Property Consultants dated 7th December
       1988 re connecting door between Units 7 & 8.

6.     Copy letter dated 16th June 1992 from Citygate Court Property Co Ltd re
       minor alterations to office suite 1 June/July 1991.

7.     Coloured copy lease plan.

8.     Photocopy Schedule of Condition in respect of Unit 7 prepared by F.G.
       Burnett (undated).

9.     Copy executed an Assignation by Thistle Well Services Ltd in favour of
       Nabors Drilling and Energy Services (UK) Ltd with consent of Citygate
       Court Property Co Ltd dated 16 September 1996 and 8 October 1996.

(d)    OFFICE SUITE 6, INTERNATIONAL BASE, GREENWELL ROAD, EAST TULLOS
       INDUSTRIAL ESTATE, ABERDEEN

1.     Photocopy draft Lease between Citygate Court Property Co Ltd and Thistle
       Well Services Ltd.

2.     Copy missives of lease (four letters) dated 16th March 1992 and
       subsequent dates.





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<PAGE>   82
3.     Extract registered Assignation by Thistle Well Services Ltd in favour of
       Coldeal Ltd registered 18th February 1993.

4.     Letter from Citygate Court Property Co Ltd dated 27th March 1992 re
       formation of new doorway between office suites 4 & 6.

5.     Copy executed an Assignation by Thistle Well Services Ltd in favour of
       Nabors Drilling and Energy Services (UK) Ltd with consent of Citygate
       Court Property Co Ltd dated 16 September 1996 and 8 October 1996.

(e)    INTERNATIONAL BASE- MISCELLANEOUS

1.     Photocopy completion certificate dated 14th May 1990 re building warrant
       B89/2709 dated 22nd December 1989.

2.     Interim Reports on Search against Thistle Well Services Ltd number 74490
       from date of incorporation to 7th July 1992.

3.     Interim Reports on Search against Thistle Well Services Ltd from 29th
       June 1987 to 8th July 1992.

(f)    SITES 15 AND 23 PITMEDDEN ROAD INDUSTRIAL ESTATE, DYCE, ABERDEEN

1.     Photocopy extract registered Lease between the Grampian Regional Council
       and Kabell (Management & Development) Ltd recorded DGRS (Aberdeen) 18th
       August 1981 (Site 15).

2.     Photocopy extract registered Lease between the Grampian Regional Council
       and Kabell (Management & Development) Ltd recorded said DGRS 18th August
       1981 (Site 23).





                                       82
<PAGE>   83
3.     Photocopy completed Lease between Kabell (Management and Development)
       Ltd and Loffland Brothers North Sea Inc dated 21st October and 9th
       November 1981 (various areas of ground generally comprising Units 15 and
       Units 23) (two copies).

4.     Photocopy extract registered Minute of Agreement between Kabell
       (Management & Development) Ltd and Loffland Brothers North Sea Inc
       registered 2nd October 1984.

5.     Photocopy extract registered Minute of Agreement between the Governor
       and Company of the Bank of Scotland and Loffland Brothers North Sea Inc
       registered 16th June 1989.

6.     Photocopy Sub-Lease between Loffland Brothers North Sea Inc and Loffland
       Nabors UK Ltd dated 21st September 1990.

7.     Extract registered Minute of Agreement incorporating Assignation and
       Variation of Lease between Loffland Brothers North Sea Inc and Nabors
       Drilling & Energy Services UK Ltd and Albany Life Assurance Co Ltd
       registered 12th January 1996 (two extracts - one with formal intimation
       attached).

8.     Quick copy Disposition by Commissioner for John Gordon and Another with
       consents to John Mcintosh and Another recorded in the Sasines Register
       for the County of Aberdeen on 18th May 1921.

9.     Quick copy Deed of Servitude by Commissioner for John Gordon and Another
       to the County Council of the County of Aberdeen recorded said Register
       of Sasines 26th September 1925.

10.    Quick copy Disposition by Trustees of James Mcintosh to Robert Lawson &
       Sons (Dyce) Ltd recorded DGRS {Aberdeen) 5th April 1967.





                                       83
<PAGE>   84
11.    Quick copy Deed of Servitude containing Disposition by Trustees of James
       McIntosh to Robert Lawson & Sons (Dyce) Ltd registered DGRS (Aberdeen)
       9th May 1967.

12.    Quick copy Disposition by Trustees of James McIntosh to Robert Lawson &
       Sons (Dyce) Ltd registered DGRS 5th April 1967.

13.    Quick copy Disposition by Trustees of James McIntosh to Dee & Don River
       Purification Board registered DGRS (Aberdeen) 9th July 1969.

14.    Property enquiry certificate issued by City of Aberdeen District Council
       dated 29th January 1991 re Units 21 and 22 Kirkton Avenue, Pitmedden
       Industrial Estate, Aberdeen.

(g)    SITE 19 PITMEDDEN ROAD INDUSTRIAL ESTATE, DYCE, ABERDEEN

1.     Extract registered Lease between the Grampian Regional Council and
       Loffland Nabors UK Ltd recorded DGRS (Aberdeen) 6th March 1992.

(h)    SITES 21 AND 22 PITMEDDEN ROAD INDUSTRIAL ESTATE, DYCE, ABERDEEN

1.     Extract registered Lease between the Grampian Regional Council and
       Loffland Nabors U.K. Ltd recorded DGRS (Aberdeen) 10th February 1992.

2.     Miscellaneous prior titles re Site 21 Pitmedden Road Industrial Estate,
       Dyce, Aberdeen.

3.     Miscellaneous prior titles re Site 22 Pitmedden Road Industrial Estate,
       Dyce, Aberdeen.





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<PAGE>   85
                                   SCHEDULE 7
                                  TAX COVENANT

1.     INTERPRETATION

1.1    In this Schedule unless the context otherwise requires:-

       "Buyer's Relief"     means:

                            (a)    any Relief which arises in respect of, by
                                   reference to or in consequence of any income
                                   profits or gains earned, accrued or received
                                   after Closing and any Event occurring after
                                   Closing;

                            (b)    any Relief which is taken into account in
                                   computing and so reducing or eliminating any
                                   provision for deferred Taxation which
                                   appears in the Consolidated Working Capital
                                   (or which, but for such Relief, would have
                                   appeared in the Consolidated Working
                                   Capital); and

                            (c)    any Relief which is treated as an asset in
                                   the Consolidated Working Capital;

       "Claim for Taxation" means any assessment, notice, demand, letter or
                            other document issued by or action taken by or on
                            behalf of any Taxation Authority or any
                            circumstances indicating that the Company or any of
                            its Subsidiaries is or may be placed or is





                                       85
<PAGE>   86
                            sought to be placed under a Liability for Taxation;

       "Event"              means any event, act, failure, omission (including
                            the failure to make sufficient distributions to
                            avoid an apportionment or deemed distribution of
                            income), transaction (including the sale of the
                            Shares pursuant to this Agreement), or change in
                            residence, whether or not the Company or any of its
                            Subsidiaries was a party thereto;

       "Liability for
       Taxation"            means:

                            (a)    any liability (including a liability which
                                   is a primary liability of some other person
                                   and whether or not there is a right of
                                   recovery against another person) to make an
                                   actual payment or increased payment of
                                   Taxation;

                            (b)    any liability (including a liability which
                                   is a primary liability of some other person
                                   and whether or not there is a right of
                                   recovery against another person) to make a
                                   payment or increased payment of Taxation
                                   which would have arisen but for being
                                   satisfied, avoided or reduced by any Buyer's
                                   Relief; and

                            (c)    the disallowance, loss, clawback, reduction,
                                   restriction or modification of





                                       86
<PAGE>   87
                                   any Buyer's Relief within paragraph (b) or
                                   (c) of the definition of Buyer's Relief;

       "Relief"             includes any relief, saving, allowance, deduction,
                            exemption or set-off relevant to the computation of
                            any Liability for Taxation, any credit against
                            Taxation or any right to a repayment of Taxation;

       "Taxation"           includes (without limitation):

                            (a)    within the United Kingdom advance
                                   corporation tax, capital gains tax,
                                   corporation tax, customs and excise duties,
                                   income tax (including PAYE), inheritance
                                   tax, insurance premium tax, national
                                   insurance contributions, petroleum revenue
                                   tax, rates and community charge, stamp duty,
                                   stamp duty reserve tax and VAT;

                            (b)    outside the United Kingdom (and in
                                   particular in the United States of America),
                                   all taxes on gross or net income, profits or
                                   gains and taxes on receipts, sales, use,
                                   occupation, franchise, value added and
                                   personal property;

                            (c)    all former taxes and all other levies,
                                   imposts, duties, charges or withholdings in
                                   the nature of taxes imposed by any Taxation
                                   Authority;





                                       87
<PAGE>   88
                            (d)    any payment which the Company or any of its
                                   Subsidiaries may be or become bound to make
                                   to any person in respect of any taxation or
                                   as a result of any enactment relating to any
                                   taxation and any obligation to repay any
                                   payment received for group relief,
                                   surrenders of advance corporation tax or
                                   refunds of taxation; and

                            (e)    all interest, penalties, fines and other
                                   charges arising out of the above or to a
                                   failure to make any return or supply any
                                   information in connection with any of the
                                   above;

       "Taxation Authority" means the Inland Revenue, HM Customs & Excise, the
                            Department of Social Security and any other body
                            having functions in relation to the administration
                            and collection of Taxation whether in the United
                            Kingdom or elsewhere.

1.2    In interpreting this Schedule:

       1.2.1  words and expressions defined elsewhere in this Agreement shall
              have the same meanings in this Schedule except where otherwise
              provided or expressly defined in this Schedule and, unless the
              context otherwise requires, Section 1.3 of this Agreement shall
              apply to the interpretation of this Schedule;

       1.2.2  any reference to income, profits or gains earned, accrued or
              received or an Event which has occurred includes income,





                                       88
<PAGE>   89
              profits or gains deemed to have been or treated as or regarded as
              earned, accrued or received or an Event deemed to have or treated
              as having or regarded as having occurred, as the case may be.

2.     COVENANT TO PAY

The Seller covenants with the Buyer to pay to the Buyer an amount equal to:

2.1    any Liability for Taxation of the Company or any of its Subsidiaries in
       respect of, by reference to or in consequence of:

       2.1.1  any income, profits or gains earned, accrued or received on or
              before Closing; or

       2.1.2  any Event which occurred on or before Closing;

2.2    any Liability for Taxation of the Company or any of its Subsidiaries
       under sections 190 and 191 TCGA, section 132 Finance Act 1988, section
       214 ICTA or section 96(8) Finance Act 1990 which would not have arisen
       but for any act or omission of any company (other than (i) any Company
       which at the time the Liability for Taxation arises is an Affiliate of
       the Buyer or (ii) the Company or any of its Subsidiaries) which was at
       any time before Closing a member of the same group of companies as the
       Company or any of its Subsidiaries for any Taxation purposes;

2.3    any Liability for Taxation of the Company or any of its Subsidiaries
       under section 767A ICTA by reason of corporation tax assessed on any
       company (other than (i) any Company which at the time the Liability for
       Taxation arises is an Affiliate of the Buyer or (ii) the Company or any
       of its Subsidiaries) and remaining unpaid where the company in question
       is or was under the control of any person who has at any time prior to





                                       89
<PAGE>   90
       Closing had control of the Company or any of its Subsidiaries (within
       the meaning in section 767B(4) ICTA);

2.4    any Liability for Taxation of the company or any of its Subsidiaries
       arising as a result of the transfer of the Excluded Assets prior to
       Closing pursuant to clause 5.6 of the Agreement;

2.5    any Liability for Taxation of the Company or any of its Subsidiaries
       arising in respect of any operations carried on in the United States of
       America prior to Closing;

2.6    any costs reasonably and properly incurred by the Company or any of its
       Subsidiaries in connection with any liability falling within 2.1 to 2.5
       above.

3.     EXCLUSIONS

The Covenant contained in paragraph 2 shall not apply and the Buyer shall have
no claim against the Seller under it to the extent that:

3.1    provision or reserve in respect of the liability in question is made in
       the Financial Statements or that payment or discharge of such liability
       has been taken into account therein or in determining the amount of the
       Consolidated Working Capital;

3.2    the Buyer has recovered damages from the Seller for breach of any of the
       Warranties in respect of the same liability or otherwise pursuant to the
       Agreement;

3.3    the liability in question arises as a result of a change in rates of
       Taxation or a change in legislation relating to Taxation or a change in
       any extra statutory concession or the published practice of any





                                       90
<PAGE>   91
       Taxation Authority, made, in each case, after Closing and with
       retrospective effect;

3.4    the claim would result in the maximum aggregate liability of the Seller
       set out in Clause 8.1 (Liability under Representatives and Warranties)
       of this Agreement being exceeded;

3.5    the claim is made outside the time limit contained in Clause 8.4 of this
       Agreement;

3.6    such claim would not have arisen but for a change in the treatment of
       assets and liabilities or of the Taxation attributable to timing
       differences (including capital allowances) in future accounts of the
       Target Group or but for any other change in the accounting bases upon
       which the Target Group prepares its future accounts except to the extent
       necessary to rectify any non-compliance with GAAP as at the date of this
       Agreement;

3.7    such claim would not have arisen but for an omission, act or transaction
       (other than an omission, act or transaction carried out pursuant to a
       legally binding obligation created on or before Closing) occurring after
       Closing otherwise than in the Ordinary Course of Business which the
       Buyer knew or ought reasonably to have known would give rise to the
       liability in question;

3.8    such claim would not have arisen or would have been reduced or
       eliminated but for a failure on the part of any member of the Target
       Group to make any claim, election, surrender or disclaimer or give any
       notice or consent or do any other thing after Closing the making, giving
       or doing of which was taken into account in preparing the Financial
       Statements or determining the Consolidated Working Capital and which was
       reasonably apparent from the face thereof;





                                       91
<PAGE>   92
3.9    to the extent that the claim or breach would not have arisen but for
       some act, omission, transaction or arrangement whatsoever carried out at
       the written request of the Buyer prior to Closing;

4.     AMOUNT OF LIABILITY FOR TAXATION

The amount of any Liability for Taxation shall be as follows:

4.1    to the extent that a Liability for Taxation involves a liability of the
       Company or any of its Subsidiaries to make an actual payment or
       increased payment of Taxation, the amount of such payment or increased
       payment;

4.2    to the extent that a Liability for Taxation involves a liability of the
       Company or any of its Subsidiaries to make a payment or increased
       payment of Taxation which would have arisen but for being satisfied,
       avoided or reduced by any Buyer's Relief, the amount of Taxation which
       the Buyer's Relief in fact saves;

4.3    to the extent that a Liability for Taxation involves the disallowance,
       loss, clawback, reduction, restriction or modification of any Buyer's
       Relief (other than a right to a repayment of Taxation) which has been
       taken into account in the Consolidated Working Capital, the amount by
       which the working capital of the Company or its Subsidiaries as shown in
       the Consolidated Working Capital Statement would have been reduced but
       for the presumed availability of the Buyer's Relief; and

4.4    to the extent that a Liability for Taxation involves the disallowance or
       reduction by any Taxation Authority of a right to a repayment of
       Taxation, the amount of the repayment so disallowed or lost.





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<PAGE>   93
5.     TIME FOR PAYMENT

5.1    Any amount which the Seller is obliged to pay to the Buyer under this
       Schedule shall be paid in cleared funds on or before the following dates
       (or, if later, the fifth Business Day after the Buyer notifies the
       Seller of the relevant Claim in accordance with paragraph 6.1):

       5.1.1  in the case of a Liability for Taxation which involves a
              liability of the Company or any of its Subsidiaries to make an
              actual payment or increased payment of Taxation, the fifth
              Business Day prior to the date on which the Taxation is due and
              payable to the relevant Taxation Authority;

       5.1.2  in the case of a Liability for Taxation which involves a
              liability of the Company or any of its Subsidiaries to make a
              payment or increased payment of Taxation which would have arisen
              but for being satisfied, avoided or reduced by the use by the
              Company or any of its Subsidiaries of any Buyer's Relief, the
              fifth Business Day prior to the date on which the Taxation would
              have been payable to the relevant Taxation Authority;

       5.1.3  in the case of a Liability for Taxation which involves the
              disallowance or reduction by any Taxation Authority of a right to
              repayment of Taxation, the fifth Business Day after the date on
              which such repayment of Taxation would otherwise have been due to
              be made by such Taxation Authority; and

       5.1.4  in any other case, the fifth Business Day after service by the
              Buyer to the Seller of a written demand for payment.

5.2    If any amount payable by the Seller to the Buyer under this Schedule is
       not paid on or before the due date for payment, that sum shall carry





                                       93
<PAGE>   94
       interest at the rate of 2 per cent above the base lending rate of
       National Westminster Bank plc from the due date until payment.

6.     CONDUCT OF CLAIMS

6.1    If the Buyer becomes aware of any Claim for Taxation which could give
       rise to a claim being made by the Buyer under this Schedule or the
       warranties contained in Clause 9 of Schedule 8 of the Agreement it shall
       notify the Seller as soon as reasonably practicable.

6.2    The Buyer agrees (if the Seller indemnifies and secures the Buyer and
       the Company or any of its Subsidiaries to the reasonable satisfaction of
       the Buyer against any loss, liability, costs or damages which may
       thereby be incurred including the Taxation the subject matter of the
       Claim) to take and procure that the Company or any of its Subsidiaries
       shall take such action and give such information and assistance as the
       Seller may reasonably request to resist, appeal or compromise any Claim
       for Taxation notified to the Seller in accordance with paragraph 6.1.

6.3    The action which the Seller may request under paragraph 6.2 shall
       include the Buyer or the Company or any of its Subsidiaries applying to
       postpone (so far as legally possible) the payment of any Taxation and
       allowing professional advisers nominated by the Seller (subject to
       approval by the Buyer, such approval not to be unreasonably withheld or
       delayed) to take over at the Seller's own expense the conduct of all
       negotiations and proceedings in connection with the Claim for Taxation.

6.4    The Seller shall keep the Buyer fully informed as to any action taken or
       postponed to be taken in conjunction with the conduct of all
       negotiations and proceedings of whatever nature arising in connection
       with the such dispute and all other relevant matters and shall supply to





                                       94
<PAGE>   95
       the Buyer in advance copies of all returns and communications proposed
       to be made to any Taxation Authority.

7.     RELIEFS

7.1    If the auditors for the time being of the Company or its Subsidiaries
       shall determine (at the request and expense of the Seller) that any
       Liability for Taxation which has resulted in a payment having been made
       by the Seller under this Schedule or the Warranties contained in Clause
       9 of Schedule 8 of the Agreement has given rise to a Relief for the
       Company, any of its Subsidiaries or the buyer which would not otherwise
       have arisen or subject to Clause 8.2 that the provision for Taxation in
       the Consolidated Working Capital Statement was an overprovision, then,
       as and when the liability of the Company, its Subsidiaries or the Buyer
       to make an actual payment of or in respect of Taxation is reduced by
       reason of that Relief or a payment is received in respect of a Relief
       (after taking account of the effect of all other Reliefs that are or
       become available to the Company, its Subsidiaries or the Buyer including
       any Relief derived from a subsequent accounting period) from the amount
       that that liability would have been but for the availability of that
       Relief, (or in the case of an overprovision forthwith upon the
       determination of the auditors) the amount by which that liability is so
       reduced or the amount of the payment or the amount of the overprovision
       shall be dealt with in accordance with paragraph 7.3.

7.2    The amount of the overprovision shall be calculated on the basis that no
       overprovision may arise or be increased by:-

       7.2.1  a retrospective change in the law of Taxation announced after
              Closing;

       7.2.2  any Relief arising after Closing; or





                                       95
<PAGE>   96
       7.2.3  any act of the Buyer or the Company carried out after Closing
              except if any of clause 3.7, clause 3.8, or clause 3.9 hereof are
              applicable.

7.4    Where it is provided under paragraph 8.1 that any amount (the "Relevant
       Amount") is to be dealt with in accordance with this paragraph:-

       7.4.1  the Relevant Amount shall first be set off against any payment
              then due from the Seller under this Schedule or under the
              Agreement in respect of the Warranties contained in clause 9 of
              Schedule 8 of the Agreement; and

       7.4.2  to the extent there is an excess of the Relevant Amount over any
              payment referred to in clause 7.4.1 hereof, a refund shall be
              made to the Seller of any previous payment or payments made by
              the Seller under this Schedule or under the Agreement in respect
              of the Warranties contained in clause 9 of Schedule 8 of the
              Agreement and not previously refunded under this paragraph up to
              the amount of such excess; and

       7.4.3  to the extent that the excess referred to in paragraph 7.4.2 is
              not exhausted under that paragraph, except in the case of an
              overprovision the remainder of that excess shall be carried
              forward and set off against any future payment or payments which
              become due from the Seller under this Schedule or under the
              Agreement in respect of the Warranties contained in clause 9 of
              Schedule 8 of the Agreement and in the case of an overprovision
              the amount of the excess shall be paid to the Seller forthwith.





                                       96
<PAGE>   97
7.4    The Buyer shall use its reasonable endeavours to procure that the
       auditors make a timely determination when requested to do so by the
       Seller for the purposes of paragraph 7.1 hereof.

7.5    For the avoidance of doubt, the amount of any overprovision shall
       include not only the amount of any provision for Taxation in the
       Consolidated Working Capital to the extent the same is determined to
       have been an overprovision, but also the amount of any Tax Refund of any
       Company arising as a result of any Event on or before Closing, to the
       extent the same was not reflected in the Consolidated Working Capital or
       exceeds the amount of any Tax Refund reflected in the Consolidated
       Working Capital other than any Tax Refund received in connection with
       the litigation referred to in Section 6.2 of the Agreement.  Where the
       auditors determine no Tax Refund has been received or that a Tax Refund
       has been received and in either case the amount is less than that
       provided in the Consolidated Working Capital, the amount of such
       shortfall shall be treated as reducing any overprovision for Taxation.





                                       97
<PAGE>   98
8.     CLAIMS AGAINST THIRD PARTIES

8.1    Where the Seller has made a payment under this Schedule or the
       Warranties contained in clause 9 of Schedule 8 of the Agreement and the
       Company or any of the Subsidiaries is entitled to recover from any third
       party (including a Taxation Authority but excluding the Buyer, the
       Company or any of the Subsidiaries) any sum in respect of the matter to
       which the payment made by the Seller relates (including recoveries by
       way of discount, credit or set-off), the Buyer shall or shall procure
       that the Company or any of its Subsidiaries shall (at the request and
       expense of the Seller and upon the Seller indemnifying and securing the
       Buyer, the Company and its Subsidiaries against all costs or expenses
       which may thereby be incurred) subject to paragraph 8.3, take such
       action as the Seller may reasonably request to enforce such recovery
       against the person in question.

8.2    The Buyer shall account to the Seller for any sums recovered in
       accordance with paragraph 8.1 (including any interest or repayment
       supplement paid by such a person) net of Taxation (if any) on such sum
       and after deduction of any costs or expenses reasonably incurred by the
       Buyer, the Company or any of its Subsidiaries in recovering such sum,
       provided that the amount paid by the Buyer under this paragraph
       (excluding interest or repayment supplement) shall not exceed the amount
       paid by the Seller in respect of the relevant claim under Warranties
       contained in clause 9 of Schedule 8 of the Agreement.





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9.     TAXATION ON PAYMENTS BY SELLER

9.1    All payments by the Seller under this Schedule shall be made in full
       without any deduction or withholding (whether in respect of Taxation,
       set-off, counter claim or otherwise) unless the deduction or withholding
       is required by law, in which case the Seller shall forthwith pay to the
       Buyer such additional amount as will ensure that the Buyer receives a
       net amount equal to the full amount which it would have received but for
       such deduction or withholding.  The Buyer shall account to the Seller
       for the benefit of any credit obtained by the Buyer in respect of the
       deduction or withholding.

9.2    If any payment received by the Buyer under this Schedule is subject to
       Taxation, the Seller shall pay to the Buyer such additional amount
       (after taking into account any Taxation payable in respect of such
       additional amount) as will ensure that the Buyer receives a net amount
       equal to the full amount which it would have received had the payment
       not been subject to Taxation.

9.3    The provisions of paragraph 9 shall not apply to interest payable under
       paragraph 5.2





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10.    ASSIGNMENT

The benefit of the provisions of this Schedule 10 shall not be assigned by the
Buyer.

11.    BUYER'S INDEMNITY

11.1   The Buyer agrees to indemnify the Seller against any liability which the
       Seller may incur under section 767A and section 767B ICTA as a result of
       a failure by the Company or any of the Subsidiaries to discharge any
       liability for Taxation for which provision has been made in the
       Consolidated Working Capital Statement (for itself and as agent for any
       company controlled by the Seller).

11.2   The Seller shall use any amount paid by the Buyer pursuant to clause
       11.1 to discharge the liability for Taxation which has given rise to the
       Claim.





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                                   SCHEDULE 8
                                   WARRANTIES

1.     ORGANIZATION, QUALIFICATION, AND CORPORATE POWER

Each of the Company and its Subsidiaries is a company duly organized and
validly existing under the laws of the jurisdiction of its incorporation.  Each
of the Company and its Subsidiaries is duly authorised to conduct business in
the United Kingdom.  Each of the Company and its subsidiaries is duly
authorised under the laws of each jurisdiction where such qualification is
required, except where the lack of such qualification would not have a material
adverse effect on the financial condition of the Company and its Subsidiaries
taken as a whole. Each of the Company and its Subsidiaries has full corporate
power and authority to carry on the businesses in which it is engaged and to
own and use the properties owned and used by it.  Schedule 1 lists the
directors and secretary of each of the Company and its Subsidiaries.

2.     CAPITALIZATION

The Seller owns the entire legal and beneficial interest in the Company Shares
free and clear of Encumbrances. The Company Shares constitute the whole of the
Company's allotted and issued share capital and are fully paid or credited as
fully paid.  There are no outstanding or authorised options, warrants, purchase
rights, subscription rights, conversion rights, exchange rights, or other
contracts or commitments that could require the Company or any of the
Subsidiaries to issue, sell, or otherwise cause to become outstanding any of
its share capital.  There is no Encumbrance on, over or affecting any of the
Company Shares or any unissued shares, debentures or other securities of any
member of the Target Group and no person has, or has claimed, the right
(whether exercisable now or in the future and whether contingent or not) to
call for the issue or transfer of any shares, debentures or other securities of
any member of the Target Group.





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3.     NONCONTRAVENTION

Neither the execution and the delivery of this Agreement, nor any of the
Ancillary Documents nor the consummation of the transactions contemplated
hereby, will (i) violate any constitution, statute, regulation, rule,
injunction, judgment, order, decree, ruling, charge, or other restriction of
any government, governmental agency, or court to which any of the Company and
its Subsidiaries is subject or (ii) violate any provision of the Memorandum or
Articles of Association of any of the Company and its Subsidiaries or (iii)
conflict with, result in a breach of, constitute a default under, result in the
acceleration of, create in any party the right to accelerate, terminate,
modify, or cancel, or require any notice under any agreement, contract, lease,
license, instrument, or other arrangement to which any of the Company and its
Subsidiaries is a party or by which it is bound or to which any of their
respective assets is subject (or result in the imposition of any Encumbrance
upon any of their respective assets) or (iv) of itself result in the creation
of an Encumbrance on any of the assets of the Target Group; or (v) of itself
result in any member of the Target Group losing the benefit of any Licence.
None of the Company and its Subsidiaries needs to give any notice to, make any
filing with, or obtain any authorisation, consent, or approval of any
government or governmental agency in order for the Parties to consummate the
transactions contemplated by this Agreement.

4.     BROKERS' FEES

None of the Company and its Subsidiaries has any liability or obligation to pay
any fees or commissions to any broker, finder, or agent with respect to the
transactions contemplated by this Agreement.





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5.     ASSETS AND STOCK

5.1    All assets included in the Financial Statements or acquired by the
       Company or its Subsidiaries since the Accounts Date and all assets owned
       by the Company and each Subsidiary are:-

       (i)    legally and beneficially owned by the Target Group free from any
              Encumbrance;

       (ii)   in the possession or under the exclusive control of the Target
              Group; and

       (iii)  where subject to a requirement for a Licence, duly licensed or
              registered in the sole name of a member of the Target Group.

5.2    The Asset register marked "A" attached to the Disclosure Letter
       comprises a record which is true, complete and accurate as to the plant,
       machinery, equipment and vehicles owned by or leased to each member of
       the Target Group and actively used in the performance of its business.

5.3    All equipment (other than the Drill Pipe and Instrumentation, in respect
       of which no such warranty is given) owned by or leased to the Target
       Group or parties to the Contracts (other than the Target Group) which is
       located on the relevant platforms on which services are being provided
       pursuant to the Contracts at the date of this Agreement and which is
       required for the performance of such services has been maintained in
       accordance with good oilfield practice.

5.4    No member of the Target Group is a party to a lease or hire, agreement
       in respect of the assets listed in the asset register marked "A"
       attached to the Disclosure Letter, nor party to any such agreement in
       respect of any other assets under which there is an obligation to make
       an annual payment in excess of Pound Sterling 50,000 or a hire purchase,
       credit





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       sale or conditional sale agreement, under which there is an outstanding
       obligation to make payments in excess of Pound Sterling 50,000.

5.5    No member of the Target Group has purchased any raw materials or
       finished products on terms that title thereto does not pass until full
       payment is made.

6.     SUBSIDIARIES

6.1    Schedule 1 sets forth for the Company and each Subsidiary as a true and
       complete record of (i) its name and registered office, (ii) its
       authorised and issued share capital of each class, and (iii) the names
       of the registered holders of the issued shares and the number of shares
       held by each such holder.  All of the shares of the Company and each
       Subsidiary have been duly authorised, validly issued and are fully paid.
       Neither the Company nor any Subsidiary currently holds or has at any
       time held any shares or any interest therein in any other company (save
       for the Company's holding of shares in the Subsidiaries).

6.2    TWSL is and has been since the Accounts Date dormant as defined in
       Section 250(3) of the Act.





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7.     FINANCIAL STATEMENTS

7.1    Attached to the Disclosure Letter are the Financial Statements and the
       Most Recent Financial Statements.  The Financial Statements (including
       the notes thereto) and the Most Recent Financial Statements have been
       prepared in accordance with GAAP applied on a consistent basis
       throughout the period covered thereby and present a true and fair view
       of the financial condition of the Company and its Subsidiaries as of
       such dates and the results of the operation of the Company and its
       Subsidiaries for such periods PROVIDED, HOWEVER, that the Most Recent
       Financial Statements are subject to normal year-end adjustments and lack
       footnotes and other presentation items and do not include any income,
       expenditure or capital sum referable to the U.S. branch assets as
       described in Schedule 5.

7.2    The Financial Statements have been prepared on a basis and using
       accounting conventions, standards, principles and practices which are
       consistent in all material respects for the three financial years ended
       on the Accounts Date.

7.3    The Company's and its Subsidiaries' accounting reference date is as set
       out in Schedule 1 and has not at any time in the 3 years prior to the
       Accounts Date been any other date.

7.4    Since the Accounts Date:

       (i)    the business of Target Group has been carried on in the ordinary
              and usual course so as to maintain the business as a going
              concern;

       (ii)   no distributions within the meaning of Part VIII of the Act or of
              ICTA have been declared paid or made by any member of the Target
              Group except as provided in the Accounts;





                                      105
<PAGE>   106
       (iii)  no share or loan capital of any Target Group has been or agreed
              to be issued allotted redeemed purchased or repaid by any member
              of the Target Group;

       (iv)   no asset with a book value in excess of Pound Sterling 50,000 
              (nor assets with an aggregate book value in excess of Pound
              Sterling 500,000) have been acquired or disposed of by any member
              of the Target Group except for current assets in the ordinary and
              usual course of trading;
        
       (v)    no contract, arrangement or transaction has been entered into and
              no payment has been made by any member of the Target Group
              otherwise than in the Ordinary Course of Business and on entirely
              arm's length terms;

       (vi)   no single item of capital expenditure has been or agreed to be
              incurred and no single commitment of a capital nature has been or
              agreed to be entered into exceeding Pound Sterling 50,000 (nor 
              capital expenditure or commitments of a capital nature in an
              aggregate amount of Pound Sterling 500,000) in total by any
              member of the Target Group;
        
       (vii)  no resolution of the shareholders of any member of the Target
              Group has been passed;

       (viii) to the Knowledge of the Seller, there has not been any material
              adverse change in the financial condition of the Company and its
              Subsidiaries taken as a whole.

7.5    Each member of the Target Group's accounts, books, ledgers, financial
       and other records are in its possession or under its control, up





                                      106
<PAGE>   107
       to date and contain a record of all matters required to be entered  in
       them by the Act, GAAP and other relevant legislation.

8.     LEGAL COMPLIANCE

8.1    To the Knowledge of the Seller, each of the Company and its Subsidiaries
       has complied with all applicable laws (including rules, regulations,
       codes, plans, injunctions, judgments, orders, decrees, rulings, and
       charges thereunder).

8.2    Neither the Seller nor any member of the Target Group has received
       written notice of any current, pending or threatened governmental,
       regulatory or other investigation, enquiry or disciplinary action
       regarding any member of the Target Group.

8.3    To the Knowledge of the Seller, each member of the Target Group has all
       necessary Licences for the proper carrying on of its business in the
       United Kingdom and each Licence is valid, in force and unconditional or
       subject only to a condition that has been fulfilled and under which no
       further action is required.

8.4    All returns, particulars, resolutions and other documents required to be
       delivered to the Registrar of Companies by each member of the Target
       Group have been properly prepared and delivered.

8.5    The copy of the memorandum and articles of association of the Target
       Group attached to the Disclosure Letter is true, complete, accurate and
       up-to-date and includes copies of all resolutions or agreements required
       by law to be annexed to it and each register, minute book and other book
       required to be kept by the Act has been properly kept, is up-to-date and
       contains a true, accurate and complete record of the matters which
       should be dealt with in those books and no notice or





                                      107
<PAGE>   108
       allegation that any of them is incorrect or should be rectified has been
       received.

8.6    Due compliance has been made with the provisions of the Act and other
       legal requirements in connection with the formation of each member of
       the Target Group, the allotment and issue, purchase and redemption of
       shares, debentures or other securities of the Target Group, the payment
       of dividends, any reduction of share capital and no notice or allegation
       has been received that any of the foregoing is incorrect of should be
       rectified.

8.7    No member of the Target Group has received notice that any of the
       Licences necessary for the operation of their respective businesses has
       been or will be cancelled or not renewed.

9.     TAX MATTERS

9.1    Each of the Company and its Subsidiaries has filed all Tax returns that
       it was required to file, and has paid all Tax shown thereon as owing,
       except where the failure to file Tax returns or to pay Tax would not
       have a material adverse effect on the financial condition of the Company
       and its Subsidiaries taken as a whole.

9.2    The Disclosure Letter lists all Tax returns filed with respect to any of
       the Company and its Subsidiaries for taxable periods ended on or after
       31 December 1990, and indicates those Tax returns that have been subject
       to Inland Revenue enquiry and indicates those Tax returns that are
       currently subject to audit.

9.3    None of the Company and its Subsidiaries has waived any statute of
       limitations in respect of taxes or agreed to any extension of time with
       respect to an Tax assessment or deficiency except as noted in the
       Disclosure Letter.





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9.4    None of the Company and its Subsidiaries is a party to any Tax
       allocation or sharing agreement.

10.    REAL PROPERTY

10.1   To the Seller's Knowledge all members of the Target Group have obtained
       planning permission in terms of the Planning Acts and all necessary
       consents and warrants required under the Buildings Regulations with
       respect to any development of an alteration or addition to the
       Properties carried out by such member.

10.2   With regard to any property held on lease by any member of the Target
       Group and forming part of the Properties true, accurate and complete
       copies of each relevant lease of any such property to any such member
       have been supplied to the Buyer each such lease is valid and subsisting
       and no member of the Target Group has received notice of any dispute or
       claim outstanding thereunder.

10.3   No member of the Target Group has contracted to purchase or lease any
       property for future settlement nor has any such member contracted or
       agreed to dispose of or in any way alienate any of the Properties.

10.4   The Properties are held subject to and with the benefit of the tenancies
       (which expression includes sub-tenancies and sub-under tenancies) as set
       out in Part 2 of the Schedule 6 and none others.

10.5   With respect to such tenancies referred to in paragraph 10.4:

       10.5.1 true, accurate and complete copies of each relevant tenancy of
              any such property by all members of the Target Group have been
              supplied to the Buyer such tenancy is valid and subsisting,





                                      109
<PAGE>   110
              no member of the Target Group has received notice of any dispute
              or claims outstanding thereunder;

       10.5.2 the relevant member of the Target Group has observed and
              performed the covenants on the part of the landlord thereunder.

10.6   No member of the Target Group has in relation to the Properties been
       served with any notices at the instance of the Local Authority as
       environmental health authority or other official regulatory body or
       authority in respect of any breach of legislation, regulations, codes of
       practice, circulars or guidance notes made thereunder relating to:
       waste; contaminated land; discharges to land, ground and surface water
       and sewers; emissions to air; noise; dangerous, hazardous or toxic
       substances of materials;  nuisance; health and safety.

11.    MATERIAL CONTRACTS

11.1   Attached to the Disclosure Letter are true, accurate and complete copies
       of the Contracts and any amendments thereto which comprise all of the
       contractual terms and material written arrangements and understandings
       (whether or not legally binding) between the parties to the Contracts.

11.2   There are no drilling contracts or other material written arrangements
       or understandings in relation to drilling (whether or not legally
       binding) to which any member of the Target Group is a party other than
       the Contracts.

11.3   No member of the Target Group is a party to, or subject to, any
       contract, or material written arrangement or understanding (whether or
       not legally binding) the performance or discharge of which could involve
       consideration or payment in excess of Pound Sterling 50,000 and which:-





                                      110
<PAGE>   111
       11.3.1 is long term (ie. not terminable on 90 days' notice or less
              without payment of compensation or damages);

       11.3.2 is not wholly on an arm's length basis in the Ordinary Course of
              Business;

       11.3.3 expressly restricts its freedom to carry on its business in any
              part of the world in such manner as it thinks fit;

       11.3.4 is an outstanding offer, tender, proposal, estimate or quotation
              which, if accepted or incorporated into a contract would
              constitute a contract which, if now in existence, would fall
              within any of paragraphs 11.2 or 11.3 and which would account for
              more than 5% of the turnover for 1996 as shown in the Most Recent
              Financial Statements;

       11.3.5 is a distributorship, agency or management agreement or
              arrangement;

       11.3.6 accounted for more than 5% of the Target Group's turnover in the
              period since the Accounts Date as shown by the Most Recent
              Financial Statements.

11.4   Save as disclosed in the Financial Statements, there is not outstanding
       any guarantee, indemnity or suretyship given by or for the benefit of
       any member of the Target Group.

11.5   To the Knowledge of the Seller no Contract has been terminated and no
       notice of termination or intention to terminate has been served by or on
       any member of the Target Group in respect of any of the Contracts.

11.6   There will at Closing be no outstanding obligations and no continuing
       contracts or arrangements between any member of the Retained Group





                                      111
<PAGE>   112
       and the Target Group except as contemplated by this Agreement or any of
       the Ancillary Documents.

12.    POWERS OF ATTORNEY

There are no outstanding powers of attorney executed on behalf of any of the
Company and its Subsidiaries.

13.    LITIGATION

The Disclosure Letter sets forth each instance in which any of the Company and
its Subsidiaries (i) is subject to any outstanding injunction, judgment, order,
decree, ruling, or charge or (ii) is a party to any action, suit, proceeding,
hearing, or investigation of, in, or before any court or quasi-judicial or
administrative agency of any local, or foreign jurisdiction and to the Seller's
Knowledge no such action, suit, proceeding, hearing or investigation is pending
by or against any member of the Target Group.

14.    JOINT VENTURE

No member of the Target Group is or has agreed to become a member of any
partnership or other unincorporated association, joint venture, European
Economic Interest Grouping or consortium (other than a recognised trade
association) or other profit or income sharing arrangement.

15.    BRANCH

No member of the Target Group has any branch, agency or place of business
outside the United Kingdom and does not use its letterhead, books or vehicles
or otherwise carry on its business under any name other than its corporate
name.





                                      112
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16.    ACCURACY OF SCHEDULES

The contents of Schedules 1, 3, 4, 5, 6 and 10 are true and accurate.

17.    COMPETITION AND FAIR TRADING

17.1   No member of the Target Group has given or been requested to give an
       undertaking or written assurance (legally binding or not) to any court
       or a governmental authority or an authority of the European Communities
       or European Economic Area under the RTPA, Fair Trading Act 1973,
       Competition Act 1980, Resale Prices Act 1976, Treaty of Rome, Agreement
       on the European Economic Area or other statute or legal instrument of
       the United Kingdom or other jurisdiction.  To the Seller's Knowledge, no
       member of the Target Group is affected by an order or regulation made
       under the Fair Trading Act 1973 or Competition Act 1980 or the
       competition law of another jurisdiction or by a decision of the
       Commission of the European Communities or EFTA Surveillance Authority or
       a competition authority of another jurisdiction.

17.2   To the Seller's Knowledge, no member of the Target Group has received a
       communication or request for information relating to any aspect of the
       Target Group's business from or by the Director General of Fair Trading,
       Monopolies and Mergers Commission, Secretary of State for Trade and
       Industry, Commission of the European Communities or EFTA Surveillance
       Authority or competition or governmental authority of another
       jurisdiction.  No agreement, arrangement or conduct (by omission or
       otherwise) of any member of the Target Group has been the subject of an
       investigation, report or decision by any of those persons or bodies.





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17.3   No member of the Target Group has received any grant or subsidy which
       would be repayable as a result of the sale of the Company Shares to the
       Buyer.

18.    INSOLVENCY

18.1   In relation to each member of the Target Group:-

       18.1.1 no resolution has been passed (and no meeting has been convened,
              and no written resolution has been circulated with a view to any
              resolution), no petition has been presented and no order has been
              made for administration or winding up or for the appointment of a
              receiver or provisional liquidator;

       18.1.2 no procedure has been commenced, by the Registrar of Companies or
              any other person, with a view to striking off under section 652
              of the Act;

       18.1.3 no receiver has been appointed, no Encumbrance has been enforced,
              and no floating charge has crystallised on or over any of its
              assets, and no event has occurred or will occur by virtue of the
              execution and performance of this Agreement or the Ancillary
              Documents and the other agreements and documents referred to in
              it which would cause, or entitle any person to cause, any of
              these things to happen;

       18.1.4 it has not stopped paying its creditors, is not insolvent, and is
              not unable to pay its debts for the purposes of section 123 of
              the Insolvency Act 1986;

       18.1.5 there is no unsatisfied judgement or order of any court or
              tribunal, or award of any arbitrator, against it;





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       18.1.6 no distress, execution or other process has been levied against
              any of its assets;

       18.1.7 no meeting of its creditors, or any class of them, has been held
              or summoned, no proposal has been made for a moratorium,
              composition or arrangement in relation to any of its debts, or
              for a voluntary arrangement under Part 1 of the Insolvency Act
              1986; and

       18.1.8 no event analogous to any of the above has occurred in any
              jurisdiction.

18.2   In relation to the Seller:-

       18.2.1 no resolution has been passed, no petition has been presented and
              no order has been made for administration or winding up or for
              the appointment of a receiver or provisional liquidator;

       18.2.2 no receiver has been appointed, no Encumbrance has been enforced,
              no floating charge has crystallised and no distress, execution or
              other process has been levied, on or over any of the Company
              Shares; and

       18.2.3 no event analogous to any of the above has occurred in any
              jurisdiction.

19.    INTELLECTUAL PROPERTY

19.1   No member of the Target Group is the registered proprietor of any
       Registered Intellectual Property and there are no applications for the
       registration of any Intellectual Property by any member of the Target
       Group pending.





                                      115
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19.2   All Intellectual Property currently used in or in connection with the
       business of the Target Group and which is material to the Target Group
       as a whole is legally and beneficially owned by a member of the Target
       Group and is used exclusively by it.

19.3   To the Knowledge of the Seller, the processes and methods employed, the
       services provided, the business conducted and the products manufactured
       used or dealt with by the Target Group do not infringe any Intellectual
       Property of any third party.

20.    INSURANCE

Attached to the Disclosure Letter is a true and complete copy of the insurances
maintained for the two years prior to the date of this Agreement in respect of
the Target Group's assets and Properties which are of an insurable nature.  All
premiums under such insurances have been paid up to date, and there have been
no claims made under such insurances during the twelve months prior to the date
hereof and there are no claims outstanding thereunder.

21.    PENSION SCHEMES

21.1   Other than the Legal and General Group Personal Pension Plan ("Pension
       Plan") there are no pension, retirement benefit or similar schemes or
       arrangements for the provision of "relevant benefits" within the meaning
       of Section 612 of the Taxes Act for or in respect of the employees or
       former employees of the Company or any of the Subsidiaries and neither,
       to the Knowledge of the Seller, the Company nor any of the Subsidiaries
       is there any legally binding obligation, other than those under the
       Pension Plan, to pay any pension or make any other payment after
       retirement or death or otherwise to provide "relevant benefits" as
       aforesaid to or in respect of any employee of the Target Group.





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21.2   The level of contributions made by the Company or any of the
       Subsidiaries pursuant to, and the terms of, the Pension Plan are
       contained in the Disclosure Letter.

22.    EMPLOYMENT MATTERS

22.1   No member of the Target Group is a party (i) to any consultancy
       agreements or arrangements with any person nor to any contract for
       services to be provided to any member of the Target Group by any
       individual as a sub-contractor, outworker or otherwise where the
       consideration paid under the agreement or arrangement or contract for
       services exceeds L.25,000 nor (ii) to any written service agreements
       with any of its directors.

22.2   There are no contracts of service with employees (whether or not in
       writing) which cannot be terminated by a member of the Target Group by
       three months' notice or less without giving rise to any claim for
       damages or compensation (other than a statutory redundancy payment or
       statutory compensation for unfair dismissal) and no member of the Target
       Group has given or received notice of resignation from any of the
       employees.

22.3   Save as set out in the schedule of employees attached to the Disclosure
       Letter:

       22.3.1 no member of the Target Group has any employees with an annual
              salary in excess of L.25,000;

       22.3.2 there are no material terms and conditions of employment for any
              employee other than Target Group's written standard terms and
              conditions of employment as annexed to the Disclosure Letter;





                                      117
<PAGE>   118
       22.3.3 no employee receives or is entitled (contingently or otherwise)
              to receive any bonus, commission, variable remuneration,
              insurance, benefit in kind, motor vehicle for private use or
              other reward other than wages or salary at a fixed rate;

       and true, complete and accurate particulars of each employee's current
       remuneration, date of commencement of continuous employment (for the
       purposes of the Employment Protection (Consolidation) Act 1978) appear
       in that schedule together with such employee's age and sex as notified
       to the relevant company.

22.4   No member of the Target Group has offered or agreed to increase the
       remuneration of, or altered or sought to alter any of the terms and
       conditions of employment of, any employee compared to those shown in the
       schedule to the Disclosure Letter.

22.5   There are no trade unions or other bodies representing employees or any
       of them and no member of the Target Group recognises any trade union or
       other body representing employees or any of them.

22.6   There has been no strike or work to rule by any employee or collective
       withdrawal of labour by more than five employees for the purposes of
       industrial action within the 2 years prior to the date of this
       Agreement.

22.7   No member of the Target Group has within the period of 12 months
       preceding the date of this Agreement given notice of any redundancies to
       the Secretary of State or started consultations with any appropriate
       representative under the provisions of Part IV of the Trade Union and
       Labour Relations (Consolidation) Act 1992, nor has any member of the
       Target Group failed to comply with such obligation under that Part.





                                      118
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22.8   No member of the Target Group has within the period of 12 months
       preceding the date of this Agreement been a party to any relevant
       transfer as defined in the Transfer of Undertakings (Protection of
       Employment) Regulations 1981 nor has any member of the Target Group
       failed to comply with any duty to inform and consult any appropriate
       representative under the said Regulations.

22.9   Each member of the Target Group has in relation to each of its present
       employees complied with all terms of their contracts of employment and
       all statutes, statutory instruments, collective agreements, customs and
       practices which are binding upon it and no such member has any
       obligation to make any ex gratia payment to any such employee.

22.10  There is no share incentive scheme, share option scheme, profit sharing
       scheme or other bonus or incentive scheme for all or any employees nor
       has any proposal been announced to establish any such scheme.

22.11  No member of the Target Group has any liability as a former member,
       officer or shadow director of any person.

22.12  There are no outstanding claims or proceedings by or against any former
       employee of any member of the Target Group and the Seller has no
       knowledge of any such claim or proceedings pending or threatened.





                                      119
<PAGE>   120
                                   SCHEDULE 9
                            GUARANTEES AND SURETIES

                                     Part 1

(i)    CONTRACT DATED 1 NOVEMBER 1994 BETWEEN (1) CHEVRON UK LIMITED AND (2)
       NDESL IN RESPECT OF BRITANNIA FIELD (NO. BRT1-XA7)

       Guarantee dated 20 September 1994 between

       (1)    Chevron UK Limited and
       (2)    Nabors Industries, Inc. (guarantor)

(ii)   CONTRACT DATED 15 JULY 1995 BETWEEN (1) ELF ENTERPRISE CALEDONIAN LTD
       AND (2) NDESL (NO. CA-7400)

       Guarantee dated 20 July 1995 between

       (1)    Elf Enterprise Caledonian Ltd and
       (2)    Nabors Industries, Inc. (guarantor)

                                     Part 2

None





                                      120
<PAGE>   121
                                  SCHEDULE 10
                         DRILL PIPE AND INSTRUMENTATION


PART 1 - DRILL PIPE

                             SOVEREIGN DRILL STRING


<TABLE>
<CAPTION>
STRING                                                                 NUMBER OF
NO.                              DESCRIPTION                            JOINTS
------                           -----------                           ---------
<S>   <C>                                                                 <C>
1.    5 1/2" FH S 135 Drill Pipe Range 2, 2.90# per foot Armacor M        383
      hardbanding on box.  Internal coating TK34 Tool Joints 2"
      longer than standard Tool Unit OD 7 1/4" x 3 1/2"

2.    5" Drill Pipe S-135 Range 2, 19.5 lb/ft 4 1/2 IF Connection 6       466
      5/8" OD x 3 1/4" ID Tool Joints 2" longer than standard Armacor
      M hardbanding on box.  Internal coating PC200 c/w pressed steel
      protectors.

3.    5" Drill Pipe S-135 Range 2, 19.5 lb/ft 4 1/2 IF Connection 6       483
      5/8" OD x 3  1/4" ID Tool Joints 2" longer than standard
      Armacor M hardbanding on box.  Internal coating PC200 c/w
      pressed steel protectors.

4.    3 1/2 Grade S-135 Range 2, 13.3 lbs/ft, 3 1/2 IF Connections 4      326
      3/4" OD x 2 9/16 ID 2" longer than standard Armacor M
      hardbanding on box.  Internal coating PC200 c/w pressed steel
      protectors.

5.    3 1/2 Grade S-135 Range 2, 13.3 lbs/ft, 3 1/2 IF Connections 4      322
      3/4" OD x 2 9/16 ID 2" longer than standard Armacor M
      hardbanding on box.  Internal coating PC200 c/w pressed steel
      protectors.
</TABLE>





                                      121
<PAGE>   122
PART 2 - INSTRUMENTATION

               MARTIN DECKER TOTCO DATA ACQUISITION (DAQ) SYSTEM

The MD Totco TOTAL Data Acquisition (DAQ) System is configured with a
combination of the following "TOTAL" modules:

o      TOTAL Data Acquisition Module System 3* USX 000A
o      VISULOGGER XC Management Module
o      WITS Interface Module UY 200 B
o      SAFE Area Display Module UYX 021
o      M/D TOTCO Certification Module
o      M/D TOTCO Sensor Module

In addition, the GASWATCH - XC Gas Detection System has been installed.





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

     * To be upgraded  by MD  Totco to System  4 at no  cost (refer 2.10/1/d
       of Disclosure Bundle).

                                      122
<PAGE>   123
                                  SCHEDULE 11

                                 ESCROW ACCOUNT

1.     The Escrow Account shall be in the joint names of Baker & McKenzie of
       100 New Bridge St, London EC4 ("the Seller's Solicitors") and Pinsent
       Curtis of 69 Old Broad St, London EC2 ("the Buyer's Solicitors") and
       shall be designated "Nabors Europe Escrow Account" and the amount for
       the time being standing to its credit (including the amount of interest
       credited thereto) is hereinafter referred to as "the Deposit".

2.     Subject as ordered by a court of competent jurisdiction :-

       2.1    except as provided herein, no payment shall be made out of the
              Escrow Account;

       no payment shall be made out of the Escrow Account except in accordance
       with the bank mandate in relation to the Escrow Account which shall
       require the signature of one authorised signatory from each of the
       Seller's Solicitors and the Buyer's Solicitors;

       2.2    if Closing does not occur on or before 21 November 1996, the
              Deposit shall be paid to the Seller's Solicitors as agent for the
              Seller forthwith without further authority on the part of the
              Buyer; and

       2.3    if Closing shall occur at any time on or before 21 November 1996,
              then the Deposit shall be paid immediately following Closing to
              the Buyer's Solicitors as agent for the Buyer without further
              authority on the part of the Seller.





                                      123
<PAGE>   124
3.     The payment out to the Seller or to the Buyer of the Deposit pursuant to
       paragraph 2.3 or 2.4 above shall be without prejudice to the rights of
       the other to claim that it is lawfully entitled to all or some part of
       the Deposit pursuant to the terms of the Agreement.

IN WITNESS WHEREOF, the Parties hereto have executed this Agreement on the date
first above written.



SIGNED BY _____________     )
for and on behalf of        )
NABORS INDUSTRIES INC       )



SIGNED BY _____________     )
for and on behalf of        )
KCA DRILLING GROUP LIMITED  )



SIGNED BY _____________     )
for and on behalf of        )
ABBOT GROUP PLC             )





                                      124