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  <xsd:element abstract="true" id="smhi_InsuranceAndLossReservesMember" name="InsuranceAndLossReservesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_InvestmentInAffiliatesAmountOfPreferredEquityOffereingParticipated" name="InvestmentInAffiliatesAmountOfPreferredEquityOffereingParticipated" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="smhi_JointVentureContributionFromNoncontrollingInterest" name="JointVentureContributionFromNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_JointVentureContributionFromPreviousJointVenture" name="JointVentureContributionFromPreviousJointVenture" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_JointVentureTotalCapital" name="JointVentureTotalCapital" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="smhi_LeaseObligationMember" name="LeaseObligationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_LeasedinEquipmentMember" name="LeasedinEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_LiftboatsMember" name="LiftboatsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_LoanFacilityWithDNBBankASAMember" name="LoanFacilityWithDNBBankASAMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_LongtermDebtObligationMember" name="LongtermDebtObligationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ManagementFeeRelatedParty" name="ManagementFeeRelatedParty" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_MerchantNavyRatingsPensionFundMember" name="MerchantNavyRatingsPensionFundMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_MexMarMember" name="MexMarMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_MiddleEastAndAsiaMember" name="MiddleEastAndAsiaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_MultiemployerPlansCumulativeFundingDeficit" name="MultiemployerPlansCumulativeFundingDeficit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="smhi_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_NumberOfEquipmentAcquired" name="NumberOfEquipmentAcquired" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_NumberOfEquipmentOperated" name="NumberOfEquipmentOperated" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_NumberOfEquipmentSold" name="NumberOfEquipmentSold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OSVPartnersMember" name="OSVPartnersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OffshoreSupportVesselsMember" name="OffshoreSupportVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OtherDNBCreditFacilitiesMember" name="OtherDNBCreditFacilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OtherDirectCostsAndExpensesMember" name="OtherDirectCostsAndExpensesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_OtherLaborAndPerformanceGuarantee" name="OtherLaborAndPerformanceGuarantee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="smhi_OtherMarineServicesMember" name="OtherMarineServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OtherNoncontrollingInterestsMember" name="OtherNoncontrollingInterestsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_OtherOffshoreMarineServicesJointVenturesMember" name="OtherOffshoreMarineServicesJointVenturesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_PIPEWarrantsMember" name="PIPEWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_PaymentsForDebtorInPossessionObligations" name="PaymentsForDebtorInPossessionObligations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_PaymentsForProceedsFromDerivativeInstrumentsOperatingActivities" name="PaymentsForProceedsFromDerivativeInstrumentsOperatingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_PaymentsToAcquirePropertyPlantAndEquipmentIncludingFairValueHedges" name="PaymentsToAcquirePropertyPlantAndEquipmentIncludingFairValueHedges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_PersonnelMember" name="PersonnelMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_PoundSterlingDebtMember" name="PoundSterlingDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ProceedsFromDeposits" name="ProceedsFromDeposits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ProceedsFromInvestmentsDistributionReturnOfCapital" name="ProceedsFromInvestmentsDistributionReturnOfCapital" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ProceedsFromSaleOfPropertyPlantAndEquipmentExcludingDepositsForFutureVesselSales" name="ProceedsFromSaleOfPropertyPlantAndEquipmentExcludingDepositsForFutureVesselSales" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ProceedsFromSaleOfPropertyPlantAndEquipmentIncludingDeposits" name="ProceedsFromSaleOfPropertyPlantAndEquipmentIncludingDeposits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ProceedsFromStockOptionsAndWarrantsExercised" name="ProceedsFromStockOptionsAndWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="smhi_PropertyAndEquipmentMeasurementInput" name="PropertyAndEquipmentMeasurementInput" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant"/>
  <xsd:element id="smhi_PropertyPlantAndEquipmentExcludingConstructionInProgress" name="PropertyPlantAndEquipmentExcludingConstructionInProgress" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="smhi_RecentlyAdoptedAccountingStandardsPolicyTextBlock" name="RecentlyAdoptedAccountingStandardsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_RepairsAndMaintenanceMember" name="RepairsAndMaintenanceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_RestrictedStockVesting" name="RestrictedStockVesting" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SEACORHoldingsMember" name="SEACORHoldingsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SEACORMarlinLLCMember" name="SEACORMarlinLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ScheduleOfDeferredGainTableTextBlock" name="ScheduleOfDeferredGainTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_ScheduleOfNoncontrollingInterestTableTextBlock" name="ScheduleOfNoncontrollingInterestTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SeaCatCrewzerIIMember" name="SeaCatCrewzerIIMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SeaCoscoOffshoreLLCMember" name="SeaCoscoOffshoreLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SeacatCrewzerMember" name="SeacatCrewzerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_SharesPaidForTaxWithholdingForExerciseOfWarrants" name="SharesPaidForTaxWithholdingForExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_StandbySafetyVesselsMember" name="StandbySafetyVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_StockRepurchasedDuringPeriodValueExerciseOfWarrants" name="StockRepurchasedDuringPeriodValueExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SupplyVesselPreviouslyRetiredMember" name="SupplyVesselPreviouslyRetiredMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_SupplyVesselsMember" name="SupplyVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_TermLoanMember" name="TermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_TermLoanToAcquireTwoVesselsMember" name="TermLoanToAcquireTwoVesselsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_TimeCharterMember" name="TimeCharterMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_TwoCustomersMember" name="TwoCustomersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="smhi_WarrantsAndRightsTextBlock" name="WarrantsAndRightsTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_WarrantsIssuedInPrivatePlacementMember" name="WarrantsIssuedInPrivatePlacementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_WindFarmUtilityVesselMember" name="WindFarmUtilityVesselMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_WindcatWorkboatsMember" name="WindcatWorkboatsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-1-basis-of-presentation-and-accounting-policies-accumulated-other-comprehensive-income-details" name="statement-statement-note-1-basis-of-presentation-and-accounting-policies-accumulated-other-comprehensive-income-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-1-basis-of-presentation-and-accounting-policies-deferred-gain-activity-details" name="statement-statement-note-1-basis-of-presentation-and-accounting-policies-deferred-gain-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-1-basis-of-presentation-and-accounting-policies-deferred-revenues-details" name="statement-statement-note-1-basis-of-presentation-and-accounting-policies-deferred-revenues-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-1-basis-of-presentation-and-accounting-policies-property-and-equipment-useful-life-details" name="statement-statement-note-1-basis-of-presentation-and-accounting-policies-property-and-equipment-useful-life-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-1-basis-of-presentation-and-accounting-policies-tables" name="statement-statement-note-1-basis-of-presentation-and-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-10-noncontrolling-interests-in-subsidiaries-noncontrolling-interest-details" name="statement-statement-note-10-noncontrolling-interests-in-subsidiaries-noncontrolling-interest-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-10-noncontrolling-interests-in-subsidiaries-tables" name="statement-statement-note-10-noncontrolling-interests-in-subsidiaries-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-13-share-based-compensation-equity-incentive-plan-transactions-details" name="statement-statement-note-13-share-based-compensation-equity-incentive-plan-transactions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-13-share-based-compensation-tables" name="statement-statement-note-13-share-based-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-15-segment-information-income-loss-in-equity-method-investments-details" name="statement-statement-note-15-segment-information-income-loss-in-equity-method-investments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-15-segment-information-summary-of-reportable-segments-details" name="statement-statement-note-15-segment-information-summary-of-reportable-segments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-15-segment-information-tables" name="statement-statement-note-15-segment-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-5-income-taxes-income-tax-rate-reconciliation-details" name="statement-statement-note-5-income-taxes-income-tax-rate-reconciliation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-5-income-taxes-tables" name="statement-statement-note-5-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-6-derivative-instruments-and-hedging-strategies-derivative-instruments-details" name="statement-statement-note-6-derivative-instruments-and-hedging-strategies-derivative-instruments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-6-derivative-instruments-and-hedging-strategies-gains-losses-on-derivative-instruments-details" name="statement-statement-note-6-derivative-instruments-and-hedging-strategies-gains-losses-on-derivative-instruments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-6-derivative-instruments-and-hedging-strategies-tables" name="statement-statement-note-6-derivative-instruments-and-hedging-strategies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-7-fair-value-measurements-assets-and-liabilities-on-recurring-basis-details" name="statement-statement-note-7-fair-value-measurements-assets-and-liabilities-on-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-7-fair-value-measurements-estimated-fair-value-details" name="statement-statement-note-7-fair-value-measurements-estimated-fair-value-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-7-fair-value-measurements-other-assets-and-liabilities-at-fair-value-details" name="statement-statement-note-7-fair-value-measurements-other-assets-and-liabilities-at-fair-value-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-7-fair-value-measurements-tables" name="statement-statement-note-7-fair-value-measurements-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-8-warrants-tables" name="statement-statement-note-8-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-note-8-warrants-warrant-activity-details" name="statement-statement-note-8-warrants-warrant-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smhi_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
