【英文标准名称】:StandardGuideforUsingtheFrequencyDomainElectromagneticMethodforSubsurfaceInvestigations
【原文标准名称】:地下勘察用频域电磁法使用的标准指南
【标准号】:ASTMD6639-2001(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:2001
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:D18.01
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:electromagnetics;frequencydomainelectromagnetics;geophysics;groundconductivity;surfacegeophysics;Electromagnetictesting;Environmentalsiteassessment(ESA);Frequencydomainelectromagneticmethod;Subsurfaceinvestigation--soil/rock
【摘要】:Concepts:Thisguidesummarizestheequipment,fieldproceduresandinterpretationmethodsusedforthecharacterizationofsubsurfacematerialsandgeologicalstructureasbasedontheirpropertiestoconduct,enhanceorobstructtheflowofelectricalcurrentsasinducedinthegroundbyanalternatingelectromagneticfield.Thefrequencydomainmethodrequiresatransmitterorenergysource,atransmittercoil,receiverelectronics,areceivercoil,andinterconnectcables(Fig.5).Thetransmittercoil,whenplacedonorneartheearth''ssurfaceandenergizedwithanalternatingcurrent,inducessmallcurrentsinthenearearthmaterialproportionaltotheconductivityofthematerial.Theseinducedalternatingcurrentsgenerateasecondarymagneticfield(Hs),whichissensedwiththeprimaryfield(Hp)bythereceivercoil.Underaconstraintknownasthex201C;lowinductionnumberapproximationx201D;(McNeill,1980)andwhenthesubsurfaceisnonmagnetic,thesecondarymagneticfieldisfullyout-of-phasewiththeprimaryfieldandisgivenbyafunctionofthesevariables.where:x03C3;a
【中国标准分类号】:P13
【国际标准分类号】:07_060
【页数】:14P.;A4
【正文语种】:英语