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                                                                   EXHIBIT 10.28

          GLOBAL AMENDMENT and ASSIGNMENT AND ACCEPTANCE, dated as of October
9, 1996 (this "Global Amendment"), among: i) RIGCO NORTH AMERICA, L.L.C., a
Delaware limited liability corporation (the "Borrower"); ii) the several
lenders and other financial institutions listed on the signature pages of this
Global Amendment (individually, a "Lender", and collectively, the "Lenders")
and iii) BHF-BANK AKTIENGESELLSCHAFT, as Administrative Agent (the
"Administrative Agent") iv) HIBERNIA NATIONAL BANK, as Collateral and
Documentation Agent (the "Collateral and Documentation Agent") and v) LEHMAN
COMMERCIAL PAPER INC., as Syndication Agent, Arranger and as a Lender ("LCPI").


                             W I T N E S S E T H :


                 WHEREAS, the Borrower and LCPI are parties to the Credit
Agreement (as amended, supplemented or otherwise modified prior to the date
hereof, the "Credit Agreement") and the other Loan Documents thereunder, each
dated as of September 30, 1996;

                 WHEREAS, the parties wish to amend the Credit Agreement and
the other Loan Documents to, among other things, add the Lenders as parties to
the Credit Agreement, replace LCPI, as administrative agent and collateral and
documentation agent with the Administrative Agent and the Collateral and
Documentation Agent, respectively, and to effectuate certain other changes
requested by the Lenders, all as set forth in this Global Amendment;

                 NOW THEREFORE, in consideration of the premises, the parties
hereto agree as follows:


                 SECTION 1.  DEFINITIONS.

                 1.1  Defined Terms.  Unless otherwise defined herein and
except as set forth in this Global Amendment, terms defined in the Credit
Agreement are used herein as therein defined.

                 SECTION 2.  AMENDMENT OF CREDIT AGREEMENT.

                 2.1  Amendment to Subsection 2.10.  Subsection 2.10 of the
Credit Agreement is hereby amended by deleting such subsection in its entirety
and substituting in lieu thereof the following new subsection 2.10:

                          "2.10  Fees.  The Borrower shall pay to the Arranger
         an annual agent's fee in an amount equal to $25,000, payable on the
         Closing Date and on the first anniversary thereof.  The Arranger
         hereby acknowledges that it has received from the Borrower the agent's
         fee payable on the Closing Date.  The Arranger shall pay to each of
         the Administrative Agent and the Collateral and Documentation Agent
         for their own accounts an annual agent's fee in an amount equal to
         $25,000, payable on each of the Second Closing Date and on the first
         anniversary of the Closing Date."
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                                                                               2


                 2.2      Amendment to Subsection 3.3.  Subsection 3.3 of the
Credit Agreement is hereby amended as follows:

                 (a)      by inserting the phrase "and the other Loan Parties"
         immediately following the word "Subsidiaries" in the second line
         thereof; and

                 (b)      inserting the phrase "and the other Loan Parties
         (other than the Borrower)" immediately following the word "Borrower"
         in the third line thereof and immediately following the word
         "Borrower" in the seventh line thereof.

                 2.3      Amendment to Section 5.  Section 5 of the Credit
Agreement is hereby amended by inserting, immediately after Subsection 5.14,
the following new subsection 5.15:

                          "5.15  Monthly Schedule.  Within 10 days after the
                 end of each calendar month, provide each Lender with a
                 schedule of the number of days each Rig was in use during such
                 calendar month and the average day rate payable with respect
                 to such Rig during such month."

                 2.4      Amendment to Subsection 5.7.  Subsection 5.7 of the
Credit Agreement is hereby amended by inserting the phrase ", and the
Collateral and Documentation Agent" immediately following the words
"Administrative Agent" in the first line thereof.

                 2.5      Amendment to Subsection 5.8.  Subsection 5.8 of the
Credit Agreement is hereby amended by adding the phrase "and the operators of
the Rigs" immediately following the word "subtenants" in the second line
thereof.

                 2.6      Amendment to Subsection 9.1.  Subsection 9.1 of the
Credit Agreement is hereby amended as follows:

                 (a)      by adding the phrase "or increase any Commitment
         thereunder" immediately following the words "payment thereof" at the
         end of clause (i) of the proviso thereof;

                 (b)      by adding the phrase "without the written consent of
         all of the Lenders" immediately following the word "Collateral" in the
         second line of clause (iv) of the proviso thereof; and

                 (c)      by deleting the phrase ",in each case" immediately
         following the term "subsection 2.5" in the second line of clause (iv)
         of the proviso thereof.


                 2.7     Amendment to Subsection 9.2.  Subsection 9.2 of the 
Credit Agreement is hereby amended as follows:

                 (a)      by deleting the name and address of the
         Administrative Agent therein and substituting in lieu thereof the
         following:
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                                                                               3


                          BHF-Bank Aktiengesellschaft
                          590 Madison Avenue
                          New York, New York 10022

                          Attention:  Amanda Montgomery
                          Fax:  (212) 756-5536

                 (b)      by deleting the name and address of the Collateral
         and Documentation Agent therein and substituting in lieu thereof the
         following:

                          Hibernia National Bank
                          313 Carondelet Street
                          New Orleans, Louisiana 70130

                          Attention:  Frank Russo
                          Fax:  (504) 533-5494

                 2.8      Amendment to Subsection 9.15.  Subsection 9.15 of the
Credit Agreement is hereby amended by inserting the phrase "or prospective
Transferee" immediately following the word "Transferee" in the fifth line
thereof.

                 2.9      Amendment to Schedule I.  The Credit Agreement is
hereby amended by inserting as a new Schedule I the Schedule I attached hereto.

                 SECTION 3.  AMENDMENT OF OTHER LOAN DOCUMENTS.

                 3.1      Amendment to Section 5.3(e) of the Borrower Security
Agreement.  Section 5.3(e) of the Borrower Security Agreement is hereby amended
by inserting immediately after the word "shall" in the second line thereof the
following phrase ", after consulting with the Administrative Agent to ensure
that no Default or Event of Default has occurred and is continuing,".

                 3.2      Amendment to Warrant Agreement.  (a)  the Warrant
Agreement is hereby amended to reflect that the Borrower will, on the Effective
Date, issue, in exchange for the Warrant delivered to an affiliate of LCPI on
the Closing Date, new Warrants (the "New Warrants") to each Lender (or its
affiliate), each such New Warrant representing the ownership interest in the
Borrower specified by the Arranger to the Borrower;

                 (b)      Subsection 2.1 of the Warrant Agreement is hereby
amended by deleting such subsection in its entirety and substituting in lieu
thereof the following new subsection 2.1:

                                  "2.1.  Issuance of Warrants.  The Company
                 hereby agrees that, upon receipt for cancellation of the
                 Warrant issued on the Closing Date in favor of an Affiliate of
                 the Arranger, it will, on the Second Closing Date, issue in
                 favor of the Persons specified on Exhibit B hereto, Warrants
                 representing the percentage of Interests in the Company
                 opposite such Person's name on Exhibit B.  On the Second
                 Closing Date the Company shall deliver to such Persons Warrant
                 Certificates evidencing the Warrants issued to such Persons.
                 Each Warrant issued
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                                                                               4


                 on the Closing Date shall entitle the Holder thereof to
                 purchase from the Company the percentage of Interests in the
                 Company (after giving effect to any such exercise of the
                 Warrants) set forth opposite such Person's name on Exhibit B
                 (subject to adjustment as provided in Section 4)."

                 (c)      Exhibit B to the Warrant Agreement is hereby amended
to reflect the information specified by the Arranger to the Borrower with
respect to the ownership interests in the Borrower held by the Lenders (or
their affiliates) and represented by the New Warrants and the Company agrees to
adjust the Warrant Register to reflect the issuance on the Second Closing Date
of the New Warrants in favor of the Lenders (or their affiliates) and the
retirement of the Warrant issued on the Closing Date.

                 SECTION 4.       REPLACEMENT OF ADMINISTRATIVE AGENT AND
COLLATERAL AND DOCUMENTATION AGENT.

                 Pursuant to subsection 8.9 of the Credit Agreement, LCPI
hereby resigns as administrative agent and collateral and documentation agent
under the Credit Agreement and the other Loan Documents and LCPI and each of
the Lenders hereby appoint BHF-Bank Aktiengesellschaft as administrative agent
and Hibernia National Bank as collateral and documentation agent under the
Credit Agreement and the other Loan Documents and such parties hereby accept
such appointments.  The Borrower hereby consents to such resignation and
appointments.  Each of the Credit Agreement and the other Loan Documents are
hereby amended to reflect such resignation and appointments and BHF-Bank
Aktiengesellschaft shall be treated as the Administrative Agent and Hibernia
National Bank shall be treated as the Collateral and Documentation Agent under
the Credit Agreement and the other Loan Documents.


                 SECTION 5.       ADDITION OF LENDERS.

                 By their signature below each of the Lenders (other than LCPI
which is already a Lender) shall become a Lender party to the Credit Agreement
and the other Loan Documents with all rights, powers and obligations of a
Lender thereunder and with an aggregate Commitment as set forth on Schedule I
attached hereto.  All notices to the Lenders under the Credit Agreement shall
be given to the Lenders at the address specified on Schedule I hereto.  On the
Effective Date each of the Lenders shall transfer in immediately available
funds to LCPI at an account previously instructed by LCPI to each such Lender
the amount set forth opposite its name on Schedule I hereto.

                 SECTION 6.  MISCELLANEOUS.

                 6.1  Effectiveness.  The amendments provided for herein shall
become effective as of October 9, 1996 (the "Effective Date") upon the
satisfaction of the following condition precedent:

                 (a)      the Administrative Agent shall have received
         counterparts of this Global Amendment, duly executed and delivered by
         the Borrower and each of the other parties hereto;
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                                                                               5


                 (b)      UCC financing statements shall have been executed by
         the appropriate parties and assignments of the Ship Mortgages shall
         have been executed and filed in the appropriate filing office (with an
         accompanying opinion of Bahamian counsel with respect to such
         assignments), in each case to reflect the replacement of LCPI with
         Hibernia National Bank as Collateral and Documentation Agent, and such
         further actions as may be reasonably requested by the Arranger in
         connection with the modifications and events contemplated hereby shall
         have been taken; and

                 (c)      LCPI (or its affiliate) shall have surrendered the
         Warrant issued to its affiliate on the Closing Date and the Borrower
         shall have executed and delivered the New Warrants to each Lender (or
         its affiliate), each such New Warrant representing the ownership
         interest in the Borrower notified by the Arranger to the Borrower.

                 6.2  Representations and Warranties.  After giving effect to
the amendments contained herein, on the Effective Date, the Borrower hereby
confirms, reaffirms and restates the representations and warranties set forth
in Section 3 of the Credit Agreement; provided that each reference in such
Section 3 to "this Agreement" shall be deemed to be a reference both to this
Global Amendment and to the Credit Agreement as amended by this Global
Amendment.




                 6.3  Continuing Effect; No Other Amendments.  Except as
expressly amended or waived hereby, all of the terms and provisions of the
Credit Agreement and the other Loan Documents are and shall remain in full
force and effect.  The amendments contained herein shall not constitute an
amendment or waiver of any other provision of the Credit Agreement or the other
Loan Documents or for any purpose except as expressly set forth herein.

                 6.4  No Default.  No Default or Event of Default shall have
occurred and be continuing as of the Effective Date after giving effect to this
Global Amendment.

                 6.5  Counterparts.  This Global Amendment may be executed in
any number of counterparts by the parties hereto, each of which counterparts
when so executed shall be an original, but all the counterparts shall together
constitute one and the same instrument.

                 6.6  GOVERNING LAW.  THIS GLOBAL AMENDMENT SHALL BE GOVERNED
BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
NEW YORK.
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                 IN WITNESS WHEREOF, the parties hereto have caused this Global
Amendment to be executed and delivered by their respective duly authorized
officers as of the date first above written.


                                    RIGCO NORTH AMERICA, L.L.C.
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    BHF-BANK AKTIENGESELLSCHAFT, as 
                                    Administrative Agent and as a Lender
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    
                                    HIBERNIA NATIONAL BANK, as Collateral and 
                                    Documentation Agent and as a Lender
                                    
                                    
                                    By:
                                        Title:
                                    
                                    LEHMAN COMMERCIAL PAPER INC., as 
                                    Syndication Agent and as a Lender
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    PRIME INCOME TRUST
                                    
                                    
                                    By:
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                                    VAN KAMPEN AMERICAN CAPITAL PRIME     
                                    RATE INCOME TRUST
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    PROTECTIVE LIFE INSURANCE COMPANY
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    MERRILL LYNCH PRIME RATE PORTFOLIO
                                    
                                    By: MERRILL LYNCH ASSET MANAGEMENT L.P., 
                                    as Investment Adviser
                                    
                                    
                                    By:
                                        Title:
                                    
                                    
                                    MERRILL LYNCH SENIOR FLOATING RATE
                                      FUND, INC.
                                    
                                    
                                    By:
                                        Title:
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                                                                      SCHEDULE I


<TABLE>
<CAPTION>
              Lender                                           Commitment
              ------                                           ----------
<S>                                                            <C>
BHF-BANK AKTIENGESELLSCHAFT                                    9,800,000
590 Madison Avenue                                             
New York, NY 10022                                             
Attention:  Paul Travers                                       
Fax:  (212) 756-5536                                           
                                                               
DEAN WITTER PRIME INCOME TRUST                                 9,800,000
Two World Trade Center, 72nd Floor                             
New York, NY 10048                                             
Attention:  Rafael Scolari                                     
Fax:  (212) 392-5345                                           
                                                               
HIBERNIA NATIONAL BANK                                         3,000,000
313 Carondelet Street                                          
New Orleans, LA 70130                                          
Attention:  Bruce Ross                                         
Fax:  (504) 533-5434                                           
                                                               
LEHMAN COMMERCIAL PAPER INC.                                   16,300,000
3 World Financial center                                       
New York, NY 10285                                             
Attention:  Robert Chambers                                    
Fax:  (212) 528-6600                                           
                                                               
MERRILL LYNCH PRIME RATE PORTFOLIO                             4,900,000
Merrill Lynch Asset Management                                 
800 Scudders Mill Road                                         
Plainsboro, NJ 08536                                           
Attention:  Doug Henderson                                     
Fax:  (609) 282-2757                                           
                                                               
MERRILL LYNCH SENIOR FLOATING RATE FUND, INC.                  4,900,000
Merrill Lynch Asset Management
800 Scudders Mill Road
Plainsboro, NJ 08536
Attention:  Doug Henderson
Fax:  (609) 282-2757
</TABLE>
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<TABLE>
<S>                                                            <C>
PROTECTIVE LIFE INSURANCE COMPANY                              9,800,000
1150 Two Galleria Tower                                        
13455 Noel Road, Suite 1150                                    
Dallas, TX 75240                                               
Attention:  Mark Okada                                         
Fax:  (214) 233-4343                                           
                                                               
VAN KAMPEN AMERICAN CAPITAL                                    6,500,000
PRIME RATE INCOME TRUST                                        
1 Parkview Plaza                                               
Oakbrook Terrace, IL 60181                                     
Attention:  Jeffrey Maillet                                    
Fax:  (630) 684-6740                                           
</TABLE>