Exhibit 10.45

Third Supplemental Subsidiary Guarantee Agreement

     Third Supplemental Subsidiary Guarantee Agreement (this “Supplemental
Subsidiary Guarantee Agreement”) dated December 10, 2004, among Seabulk
International, Inc., a Delaware corporation (the “Borrower”) and Fortis Capital
Corp. (the “Agent”).

Preliminary Statement

     Pursuant to the terms of the Swap Agreements, each of the Counterparties
agreed to provide the Borrower with an interest rate swap to enable the Borrower
to manage its interest rate exposure. As a condition to providing such Swap
Agreements and any other Swap Agreements from time to time outstanding, each of
the Counterparties has requested that the Subsidiary Guarantors, jointly and
severally, guarantee the Obligations of the Borrower under the Swap Agreements
by entering into the Guarantee Agreement and securing the Subsidiary Guarantors’
obligations hereunder by granting to the Agent, on behalf of the Counterparties,
a lien in, to and under the Guarantee Collateral. The Borrower has requested
that the SEABULK MISSISSIPPI (the “Vessel”), owned by one of the Subsidiary
Guarantors, be re-flagged from the maritime registry of the Republic of Panama
to the maritime registry of the Republic of the Marshall Islands. In order to
induce the Counterparties to permit the re-flagging, Seabulk Offshore, Ltd. (the
“Owner”) has agreed to execute and deliver (and cause to be recorded where
appropriate) in favor of the Agent, on behalf of the Counterparties, any and all
documents necessary to evidence the continuation of the lien in, to and under
the Vessel and the Collateral related thereto, concurrently with or immediately
following the re-documentation of the Vessel so that the Vessel shall remain for
all purposes a “Vessel” under the Transaction Documents.

     All things necessary to make this Third Supplemental Subsidiary Guarantee
Agreement a valid agreement of the Borrower, Owner and the other Subsidiary
Guarantors in accordance with its terms have been done.

     NOW, THEREFORE, and in consideration of the premises, it is mutually
covenanted and agreed, for the equal and proportionate benefit of the Agent and
each of the Counterparties, as follows:

          (i) Owner hereby confirms that it unconditionally and irrevocably
guarantees, jointly and severally, to the Agent and the Counterparties (i) the
full and prompt payment of an amount equal to each and all of the payments and
other sums when and as the same shall become due, required to be paid by the
Borrower under each of the Swap Agreements and (ii) the full and prompt
performance and observance by the Borrower of the obligations, covenants and
agreements required to be performed and observed by the Borrower under each of
the Swap Agreements (items (i) and (ii), the “Subsidiary Guarantee
Obligations”). Owner hereby confirms that it irrevocably and unconditionally
agrees that upon any default by the Borrower in the payment, when due, of any
amounts (including amounts in respect of fees and indemnification owing to the
Agent or the Counterparties) due

 

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under the Swap Agreements, Owner will promptly pay the same within ten (10) days
after receipt of written demand therefor from the Agent or any Counterparty.
Owner further hereby confirms that it irrevocably and unconditionally agrees
that upon any default by the Borrower in any of its obligations, covenants and
agreements required to be performed and observed by the Borrower under the Swap
Agreements, Owner will effect the observance of such obligations, covenants and
agreements within ten (10) days after receipt of written demand therefor from
the Agent or any Counterparties.

     Owner further confirms that it agrees that the Subsidiary Guarantee
Obligations may be extended or renewed, in whole or in part, without notice or
further assent from Owner and that Owner will remain bound under the Subsidiary
Guarantee Agreement notwithstanding any extension or renewal of any Subsidiary
Guarantee Obligation. Owner confirms that it is subject to all the provisions of
the Subsidiary Guarantee Agreement applicable to a Subsidiary Guarantor. Without
limiting the effect of the foregoing, Owner hereby agrees that it is hereby
bound by the provisions of Section 5.02 of the Subsidiary Guarantee Agreement
relating to the assignment to the Agent as security, and hereby grants to the
Agent a security interest in (subject to the provisions of the Assignment of
Earnings and Insurances), all the freights, hires, charters and Insurances to
which Owner is entitled in respect of the Vessel and the other Vessels that it
owns subject to the Mortgages.

     SECTION 2. The Subsidiary Guarantee Agreement, as supplemented and amended
by this Third Supplemental Subsidiary Guarantee Agreement and all other
Subsidiary Guarantee Agreements supplemental thereto, is in all respects
ratified and confirmed, and the Subsidiary Guarantee Agreement, this Third
Supplemental Subsidiary Guarantee Agreement and all Subsidiary Guarantee
Agreements supplemental thereto shall be read, taken and construed as one and
the same instrument.

     SECTION 3. If any provision hereof limits, qualifies or conflicts with
another provision hereof which is required to be included in this Supplemental
Subsidiary Guarantee Agreement by any of the provisions of the Subsidiary
Guarantee Agreement, such required provision shall control.

     SECTION 4. All covenants and agreements in this Third Supplemental
Subsidiary Guarantee Agreement by Owner shall bind its successors and assigns,
whether so expressed or not.

     SECTION 5. In case any provision in this Third Supplemental Subsidiary
Guarantee Agreement shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.

     SECTION 6. Nothing in this Third Supplemental Subsidiary Guarantee
Agreement, expressed or implied, shall give to any Person, other than the
parties hereto and their successors hereunder, and the Counterparties any
benefit or any legal or equitable right, remedy or claim under this Second
Supplemental Subsidiary Guarantee Agreement.

     SECTION 7. THIS THIRD SUPPLEMENTAL CREDIT AGREEMENT SHALL BE GOVERNED BY,
AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT
GIVING EFFECT TO PRINCIPLES OF CONFLICTS OF LAW.

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     SECTION 8. All terms used in this Third Supplemental Subsidiary Guarantee
Agreement not otherwise defined herein that are defined in Appendix A to the
Subsidiary Guarantee Agreement shall have the meanings set forth therein.

     SECTION 9. This Third Supplemental Subsidiary Guarantee Agreement may be
executed in any number of counterparts, each of which shall be an original; but
such counterparts shall together constitute but one and the same instrument.

REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK

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     WHEREOF, the parties have caused this Supplemental Subsidiary Guarantee
Agreement to be duly executed as of the date first written above.

SEABULK INTERNATIONAL, INC.,
as Borrower,

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Name: Patrice M. Johnston
Title: Attorney-in-Fact

 

FORTIS CAPITAL CORP.
as Agent,

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Name:
Title:

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Name:
Title:

SEABULK OFFSHORE, LTD., hereby
acknowledges and agrees to the terms,
conditions and provisions of the above
Third Supplemental Subsidiary Guarantee
Agreement.

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Name: Patrice M. Johnston
Title: Attorney-in-Fact

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