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Exhibit 99.1

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL DATA

        The following unaudited pro forma condensed combined balance sheet as of December 31, 2004 and unaudited pro forma condensed combined statement of income for the year ended December 31, 2004 (collectively the "pro forma statements") are based on the historical financial statements of SEACOR and Seabulk after giving effect for the Seabulk merger using the purchase method of accounting and our preliminary estimates, assumptions and pro forma adjustments as described in the accompanying notes to the pro forma statements. Certain reclassifications of information as presented in SEACOR's and Seabulk's historical financial statements included elsewhere herein have been made to conform to the presentation of the pro forma statements.

        The unaudited pro forma condensed combined balance sheet as of December 31, 2004 gives effect to the Seabulk merger as if it had occurred on that date. The unaudited pro forma condensed combined statement of income for the year ended December 31, 2004 has been prepared to illustrate the effects of the Seabulk merger as if it had occurred on January 1, 2004. Preliminary estimates, assumptions and pro forma adjustments to state the acquired assets and liabilities of Seabulk at fair value are as of the announcement date of the Seabulk merger, March 16, 2005. Shares of SEACOR common stock assumed issued in the pro forma statements to acquire the outstanding Seabulk shares as of the announcement date were valued using an average market price over a period of days shortly before and after the announcement date. The pro forma statements are presented for information purposes only and have been derived from, and should be read in conjunction with, the historical consolidated financial statements of SEACOR and Seabulk, including the notes thereto. The pro forma adjustments, as described in the notes to the pro forma statements, are based on currently available information that we believe are reasonable. These adjustments are not necessarily indicative of our financial position or results of operations that would have occurred had the Seabulk merger taken place on the dates indicated, nor are they necessarily indicative of SEACOR's future financial position or results of operations.

        Pro forma adjustments reflect an allocation of the purchase price, material charges, credits and related tax effects that are directly attributable to the Seabulk merger and to conform Seabulk's accounting policies with those of SEACOR. Certain pro forma adjustments were based on a preliminary assessment of the value of assets and liabilities acquired as part of the Seabulk merger. However, changes to adjustments included in the pro forma statements are expected as valuations of assets and liabilities are finalized and additional information becomes available. The final purchase price allocations for the Seabulk merger will be affected by formal valuation analysis of certain assets by outside appraisal firms and may result in material adjustments to the amounts presented in the pro forma statements. Furthermore, the impact of integration activities and the finalization of charges and credits directly attributable to the Seabulk merger could also cause actual results to materially differ from the pro forma statements presented herein.

Unaudited Pro Forma Condensed Combined Balance Sheet
As of December 31, 2004
(in thousands)

			SEACOR			Seabulk			Adjustments			Pro Forma Condensed Combined
ASSETS
Current Assets:
	Cash and cash equivalents		$	214,389		$	18,949		$	(108,058	)(a)	$	125,280
	Restricted cash			—			35,681			—			35,681
	Available-for-sale securities			136,992			—			(12,866	)(h)		124,126
	Accounts receivable, net			193,050			58,993			—			252,043
	Inventories			18,837			7,868			(4,114	)(b)		22,591
	Prepaid expenses and other			35,453			3,627			—			39,080
		Total current assets		598,721			125,118			(125,038	)		598,801
Investments, at Equity, and Receivables From 50% or Less Owned Companies				47,870			—			—			47,870
Property and Equipment, net				925,597			598,793			284,751	(c)		1,809,141
Construction Reserve Funds				144,006			—			—			144,006
Goodwill				28,755			—			143,303	(a)		172,058
Deferred Drydocking				—			32,377			(32,377	)(d)		—
Deferred Debt Issuance Costs				7,338			12,676			(12,676	)(e)		7,338
Other Assets				13,722			17,824			—			31,546
			$	1,766,009		$	786,788		$	257,963		$	2,810,760
LIABILITIES AND STOCKHOLDERS' EQUITY
Current Liabilities:
	Accounts payable and accrued expenses		$	63,461		$	14,918		$	—		$	78,379
	Current portion of long-term debt			13,228			16,653			—			29,881
	Current obligations under capital leases			—			3,708			—			3,708
	Other current liabilities			65,797			40,196			6,400	(f)		112,393
		Total current liabilities		142,486			75,475			6,400			224,361
Long-Term Debt and Capital Lease Obligations				582,367			507,439			(20,572	)(g)		1,069,234
Deferred Income Taxes				211,542			—			40,726	(i)		252,268
Deferred Income and Other Liabilities				28,988			4,879			—			33,867
Minority Interest in Subsidiaries				6,869			—			—			6,869
Stockholders' Equity:
	Common stock			245			234			(168	)(j)		311
	Additional paid-in capital			412,210			259,843			170,977	(j)		843,030
	Retained earnings (deficit)			551,273			(60,379	)		60,379	(j)		551,273
	Treasury shares			(197,850	)		—			—			(197,850	)
	Unearned restricted stock			(2,423	)		(758	)		758	(k)		(2,423	)
	Accumulated other comprehensive income			30,302			55			(537	)(h)		29,820
		Total stockholders' equity		793,757			198,995			231,409			1,224,161
			$	1,766,009		$	786,788		$	257,963		$	2,810,760

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Notes to Unaudited Pro Forma Condensed Combined Balance Sheet

(a)

The preliminary estimated consideration is allocated as follows (in thousands, except share data):

Consideration to purchase all outstanding Seabulk stock, warrants and options
	Cash consideration		$	98,608
	Estimated direct transaction fees and expenses			9,450
		Total cash consideration		108,058
	Premium over par paid by SEACOR for Seabulk long-term debt (see note h)			540
	6,641,270 SEACOR shares issued at $64.88 per share (exchange ratio of 0.2694)			430,886
		Total consideration		539,484
Preliminary allocation of consideration
	Book value of Seabulk net assets			(199,698	)
	Adjustments to historical net book value:
		Inventories policy change, net of $1,440 in tax (see note b)		2,674
		Property and Equipment, net of $99,663 in tax (see note c)		(185,088	)
		Drydocking policy change, net of $11,332 in tax (see note d)		21,045
		Write-off deferred debt issuance costs, net of $4,437 in tax (see note e)		8,239
		Compensation reserves, net of $2,240 in tax (see note f)		4,160
		Long-term debt, net of $3,175 in tax (see note g)		(5,897	)
		Reduction of deferred tax valuation allowance (see note i)		(42,374	)
		Unearned Seabulk restricted stock (see note k)		758
Adjustment to Goodwill			$	143,303

(b)

Represents the elimination of Seabulk's capitalized non-fuel inventories and supplies relating to its offshore marine vessel fleet to conform with SEACOR's accounting policy.

(c)

Represents preliminary purchase price adjustments to state Seabulk's acquired property and equipment at its estimated fair value of $883.5 million. Final purchase price adjustments based on the final valuation may materially differ from our preliminary estimates presented herein. Deferred tax liabilities associated with non-deductible fair market value adjustments were calculated using an income tax rate of 35% as the future depreciation of the fair market value adjustments will not be tax deductible.

(d)

Represents the elimination of Seabulk's deferred drydocking expense to conform with SEACOR's accounting policy.

(e)

Represents the elimination of Seabulk's deferred debt issuance costs as a result of stating its long-term debt at fair value (see note g).

(f)

Represents accrued payments related to various employment agreements among Seabulk and its senior officers triggered by the Seabulk merger and reserves for potential redundancies of personnel.

(g)

Represents the revaluation of Seabulk's remaining outstanding senior notes, after the elimination of $11.5 million par value of senior notes held by SEACOR (see note h), and Seabulk's Title XI debt to their estimated fair values. All other long-term debt and capital lease obligations of Seabulk are considered to approximate fair value in the pro forma statements. Final purchase price adjustments based on the final valuation of these Seabulk obligations may materially differ from our preliminary estimate presented herein.

(h)

Represents the elimination of SEACOR's investment in Seabulk's senior notes, stated at a fair value of $12.9 million, and the related unrealized gain of $0.5 million, net of $0.3 million in tax,

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against Seabulk's corresponding long-term debt of $11.5 million par value. The premium over par paid by SEACOR for its investment in Seabulk's senior notes of $0.5 million is included as additional consideration paid in the Seabulk merger.

(i)

Represents additional net deferred tax liabilities of $83.4 million recognized as a result of net of tax adjustments relating to the preliminary allocation of consideration (see note a), offset by reductions in Seabulk's valuation allowance of $42.4 million (see note a and as discussed below) and in SEACOR's deferred tax liability for unrealized gains on marketable securities of $0.3 million (see note h). As of December 31, 2004, Seabulk had outstanding deferred tax assets of $189.8 million (primarily net operating loss carryforwards and foreign tax credits), deferred tax liabilities of $127.4 million (primarily property differences) and recognized a valuation allowance of $62.4 million to offset the entire net deferred asset. The utilization of Seabulk's net operating loss carryforwards by the combined group will be subject to significant limitations; however, we have assumed that its entire net deferred tax asset will be realized except for $20.0 million of foreign tax credits for purposes of the pro forma statements. The final determination of these limitations may materially differ from our preliminary estimate presented herein.

(j)

Represents the total increase in capital for the combined group, comprised of SEACOR stock consideration of $430.9 million issued as a result of the Seabulk merger, offset by the historical net book value of Seabulk of $199.7 million.

(k)

Represents the elimination of Seabulk unvested restricted stock as a result of accelerated vesting triggered by the Seabulk merger.

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Unaudited Pro Forma Condensed Combined Statement of Income
For the Year Ended December 31, 2004
(in thousands, except per share data)

		SEACOR			Seabulk			Adjustments			Pro Forma Condensed Combined
Operating Revenues		$	491,860		$	352,328		$	—		$	844,188
Cost and Expenses:
	Operating expenses		354,163			218,039			(3,242	)(a)		568,960
	Administrative and general		61,425			37,526			—			98,951
	Depreciation and amortization		57,834			40,537			39,760	(b)		138,131
			473,422			296,102			36,518			806,042
Gains on Asset Sales			10,234			4,116			—			14,350
Operating Income			28,672			60,342			(36,518	)		52,496
Other Income (Expense):
	Interest income		8,422			309			—			8,731
	Interest expense		(22,485	)		(33,888	)		1,075	(c)		(55,298	)
	Other, net		9,677			4,624			—			14,301
			(4,386	)		(28,955	)		1,075			(32,266	)
Income Before Income Tax Expense, Minority Interest and Equity in Earnings of 50% or Less Owned Companies			24,286			31,387			(35,443	)		20,230
Income Tax Expense (Benefit)			8,573			5,189			(6,690	)(d)		7,072
Income Before Minority Interest and Equity in Earnings of 50% or Less Owned Companies			15,713			26,198			(28,753	)		13,158
Minority Interest in Net Income of Subsidiaries			(483	)		(264	)		—			(747	)
Equity in Earnings of 50% or Less Owned Companies			4,659			—			—			4,659
Net Income		$	19,889		$	25,934		$	(28,753	)	$	17,070
Basic Earnings Per Common Share		$	1.09		$	1.11					$	0.68
Diluted Earnings Per Common Share		$	1.08		$	1.09					$	0.68
Weighted Average Common Shares Outstanding:
	Basic		18,306			23,264						24,947
	Diluted		18,609			23,761						25,251

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Notes to Unaudited Condensed Combined Pro Forma Statement of Income

(a)

Represents the elimination of Seabulk's capitalized non-fuel inventories and supplies amortization of $0.6 million and a $2.6 million reduction to restate Seabulk's drydock costs to an as incurred basis to conform with SEACOR's accounting policy.



(b)

Represents the restatement of Seabulk's depreciation expense to $80.3 million resulting from our preliminary valuation of its property and equipment of $883.5 million and to conform with SEACOR's accounting policies regarding depreciable useful lives and salvage values.



(c)

Represents the elimination of Seabulk's deferred debt issuance costs and premium amortization of $1.7 million offset by an expected net increase of $0.6 million resulting from the revaluation of Seabulk's senior notes and Title XI debt.



(d)

Represents the restatement of Seabulk's Income Tax Expense to an effective tax rate of 37% as a result of the recognition of Seabulk's net operating carryforwards by the combined group.

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UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL DATA
Unaudited Pro Forma Condensed Combined Balance Sheet As of December 31, 2004 (in thousands)
Notes to Unaudited Pro Forma Condensed Combined Balance Sheet
Unaudited Pro Forma Condensed Combined Statement of Income For the Year Ended December 31, 2004 (in thousands, except per share data)
Notes to Unaudited Condensed Combined Pro Forma Statement of Income