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<!-- Creation Date      : 2021-08-04T07:04:00.6733498+00:00 -->
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  <xsd:element id="smhi_ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock" name="ScheduleOfSupplementalCashFlowInformationRelatedToLeasesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_ScheduleOfOtherInformationRelatedToLeasesTableTextBlock" name="ScheduleOfOtherInformationRelatedToLeasesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_BasisOfPresentationAndAccountingPoliciesLineItems" name="BasisOfPresentationAndAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_BasisOfPresentationAndAccountingPoliciesTable" name="BasisOfPresentationAndAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORMarineForeignHoldingsMember" name="SEACORMarineForeignHoldingsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_PrepaidVesselManagementFeesMember" name="PrepaidVesselManagementFeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_PrepaidCharterModificationAndReservationFeesMember" name="PrepaidCharterModificationAndReservationFeesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OffshoreSupportVesselsMember" name="OffshoreSupportVesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SpecialtyVesselMember" name="SpecialtyVesselMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_ConstructionReserveFundsCurrent" name="ConstructionReserveFundsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_ImpairmentOfLongLivedAssetsFourOwnedLiftboats" name="ImpairmentOfLongLivedAssetsFourOwnedLiftboats" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_ImpairmentOfLongLivedAssetsTwoLeasedInLiftboat" name="ImpairmentOfLongLivedAssetsTwoLeasedInLiftboat" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_AdditionalImpairmentOfRightToUseAssets" name="AdditionalImpairmentOfRightToUseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxNotCreditablePercent" name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxNotCreditablePercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_EffectiveIncomeTaxRateReconciliationForeignWithholdingTax" name="EffectiveIncomeTaxRateReconciliationForeignWithholdingTax" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_PaymentsToAcquirePropertyPlantAndEquipmentIncludingFairValueHedges" name="PaymentsToAcquirePropertyPlantAndEquipmentIncludingFairValueHedges" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_NumberOfEquipmentAcquired" name="NumberOfEquipmentAcquired" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_NumberOfEquipmentSold" name="NumberOfEquipmentSold" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_SetoffOfDebtUnderCreditFacility" name="SetoffOfDebtUnderCreditFacility" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_ProceedsFromPropertyPlantAndEquipmentIncludingDepositsAndGainOnSale" name="ProceedsFromPropertyPlantAndEquipmentIncludingDepositsAndGainOnSale" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_ProceedsFromDeposits" name="ProceedsFromDeposits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_DepositsForFutureSales" name="DepositsForFutureSales" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_PlatformSupplyVesselsMember" name="PlatformSupplyVesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FastSupportVesselsMember" name="FastSupportVesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_PlatformSupplyVesselsAndFastSupportVesselsMember" name="PlatformSupplyVesselsAndFastSupportVesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_AnchorHandlingTowingSupplyVesselMember" name="AnchorHandlingTowingSupplyVesselMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_VesselUnderConstructionAndOtherEquipmentMember" name="VesselUnderConstructionAndOtherEquipmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_VesselUnderConstructionMember" name="VesselUnderConstructionMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FalconGlobalUSATermLoanFacilityMember" name="FalconGlobalUSATermLoanFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_WindcatWorkboatsMember" name="WindcatWorkboatsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_ProceedsFromSaleOfPropertyPlantAndEquipmentGross" name="ProceedsFromSaleOfPropertyPlantAndEquipmentGross" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_PaymentsForTransactionsFeesAndOtherCosts" name="PaymentsForTransactionsFeesAndOtherCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_CashSoldOnPropertyPlantAndEquipmentDisposal" name="CashSoldOnPropertyPlantAndEquipmentDisposal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_MexMarMember" name="MexMarMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OSVPartnersMember" name="OSVPartnersMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORMarlinLLCMember" name="SEACORMarlinLLCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_MEXMAROffshoreMember" name="MEXMAROffshoreMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OffshoreVesselHoldingsMember" name="OffshoreVesselHoldingsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OtherOffshoreMarineServicesJointVenturesMember" name="OtherOffshoreMarineServicesJointVenturesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_ConvertibleSeniorNotesMember" name="ConvertibleSeniorNotesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORMarineForeignHoldingsCreditFacilityMember" name="SEACORMarineForeignHoldingsCreditFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SeaCatCrewzerIIITermLoanFacilityMember" name="SeaCatCrewzerIIITermLoanFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACOROffshoreDeltaFormerlyKnownAsSEACOSCOAcquisitionDebtMember" name="SEACOROffshoreDeltaFormerlyKnownAsSEACOSCOAcquisitionDebtMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORDeltaFormerlyKnownAsSEACOSCOShipyardFinancingMember" name="SEACORDeltaFormerlyKnownAsSEACOSCOShipyardFinancingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORAlpineShipyardFinancingMember" name="SEACORAlpineShipyardFinancingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACOR88888TermLoanMember" name="SEACOR88888TermLoanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FalconGlobalUSARevolverMember" name="FalconGlobalUSARevolverMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_NumberOfLiftboatsReleasedFromMortgagesAndSecurityArrangements" name="NumberOfLiftboatsReleasedFromMortgagesAndSecurityArrangements" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="smhi_ConditionalPayoffAgreementMember" name="ConditionalPayoffAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_TermAndRevolvingLoanFacilityMember" name="TermAndRevolvingLoanFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_LongtermDebtObligationMember" name="LongtermDebtObligationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_HullAndMachineryInsuranceProceeds" name="HullAndMachineryInsuranceProceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_TroubledDebtRestructuringDebtorCurrentPeriodIncreaseDecreaseOfBasicEarningsPerShare" name="TroubledDebtRestructuringDebtorCurrentPeriodIncreaseDecreaseOfBasicEarningsPerShare" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_TroubledDebtRestructuringDebtorCurrentPeriodIncreaseDecreaseOfDilutedEarningsPerShare" name="TroubledDebtRestructuringDebtorCurrentPeriodIncreaseDecreaseOfDilutedEarningsPerShare" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_NumberOfOperatingLeasesOnEquipment" name="NumberOfOperatingLeasesOnEquipment" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_LiftboatsMember" name="LiftboatsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_VesselsMember" name="VesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OtherEquipmentMember" name="OtherEquipmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FinanceLeaseCostsAbstract" name="FinanceLeaseCostsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_ExpectedCashTaxRefundsReceivable" name="ExpectedCashTaxRefundsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_InterestReceivedOnCashRefunds" name="InterestReceivedOnCashRefunds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_ProceedsOfCashTaxRefunds" name="ProceedsOfCashTaxRefunds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_TaxRefundAndIndemnificationAgreementMember" name="TaxRefundAndIndemnificationAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_InterestRateSwapAgreementThreePointThreeTwoPercentMember" name="InterestRateSwapAgreementThreePointThreeTwoPercentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_InterestRateSwapAgreementThreePointOneNineFivePercentMember" name="InterestRateSwapAgreementThreePointOneNineFivePercentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACOR88888Member" name="SEACOR88888Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DerivativesNotionalAmount" name="DerivativesNotionalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="smhi_NumberOfPropertyAndEquipmentWithFairValue" name="NumberOfPropertyAndEquipmentWithFairValue" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_PlatformSupplyVesselMember" name="PlatformSupplyVesselMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FSVOffshoreSupportVesselsMember" name="FSVOffshoreSupportVesselsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DeficiencyNoticeMember" name="DeficiencyNoticeMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SeabulkOverseasMember" name="SeabulkOverseasMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SEACORHoldingsMember" name="SEACORHoldingsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_CostAllocationPercentage" name="CostAllocationPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="smhi_GeneralAndAdministrativeExpenseIncludingShortTermLeaseExpense" name="GeneralAndAdministrativeExpenseIncludingShortTermLeaseExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_AfricaAndEuropeMember" name="AfricaAndEuropeMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_MiddleEastAndAsiaMember" name="MiddleEastAndAsiaMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_TimeCharterMember" name="TimeCharterMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_BareboatCharterMember" name="BareboatCharterMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OtherMarineServicesMember" name="OtherMarineServicesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_PersonnelMember" name="PersonnelMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_RepairsAndMaintenanceMember" name="RepairsAndMaintenanceMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DrydockingMember" name="DrydockingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_InsuranceAndLossReservesMember" name="InsuranceAndLossReservesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_FuelLubesAndSuppliesMember" name="FuelLubesAndSuppliesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OtherDirectCostsAndExpensesMember" name="OtherDirectCostsAndExpensesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_AssetsExcludingCorporateAssets" name="AssetsExcludingCorporateAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_EquityInEarningsLossesOfOwnedCompanies" name="EquityInEarningsLossesOfOwnedCompanies" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_SegmentInformationLineItems" name="SegmentInformationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_SegmentInformationTable" name="SegmentInformationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_WindcatWorkboatsLtdMember" name="WindcatWorkboatsLtdMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationLeaseExpense" name="DisposalGroupIncludingDiscontinuedOperationLeaseExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationExpenses" name="DisposalGroupIncludingDiscontinuedOperationExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationOtherNonoperatingIncomeExpense" name="DisposalGroupIncludingDiscontinuedOperationOtherNonoperatingIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationIncomeLossBeforeIncomeTaxesAndIncomeLossFromEquityMethodInvestments" name="DisposalGroupIncludingDiscontinuedOperationIncomeLossBeforeIncomeTaxesAndIncomeLossFromEquityMethodInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationIncomeTaxExpenseBenefit" name="DisposalGroupIncludingDiscontinuedOperationIncomeTaxExpenseBenefit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationIncomeLossBeforeEquityMethodInvestmentsAfterTax" name="DisposalGroupIncludingDiscontinuedOperationIncomeLossBeforeEquityMethodInvestmentsAfterTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationIncomeLossFromEquityMethodInvestments" name="DisposalGroupIncludingDiscontinuedOperationIncomeLossFromEquityMethodInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="smhi_DisposalGroupDiscontinuedOperationOperatingRevenueAbstract" name="DisposalGroupDiscontinuedOperationOperatingRevenueAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DisposalGroupDiscontinuedOperationCostsAndExpensesAbstract" name="DisposalGroupDiscontinuedOperationCostsAndExpensesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_DisposalGroupIncludingDiscontinuedOperationOtherNonoperatingIncomeExpenseAbstract" name="DisposalGroupIncludingDiscontinuedOperationOtherNonoperatingIncomeExpenseAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="smhi_OtherRevenueMember" name="OtherRevenueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
</xsd:schema>
