用大地电磁勘探方法研究大陆动力学(英文)
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摘要
大地电磁法通过测量地表的天然电场和磁场来提供地壳和上地幔的电阻率图像。在仪器和处理解释技术方面的进展使得大地电磁法现在能够快速采集大地电磁数据并进行二维或三维地质模型解释。由于电阻率对地下连通的流体 (如局部熔融和水 )反应灵敏 ,大地电磁资料能够给出地球介质结构成分和流变特性的信息 ,作为地震勘探所获得信息的补充。大地电磁法现在被应用于对构造运动活跃区域的大陆动力学研究。对美国圣安德烈斯断层的大地电磁研究已经揭示了地震比较活跃的断层区段和在脆性上地壳中的断裂带的电阻率之间的相关性。在青藏高原采集的大地电磁资料描绘了地壳中的主要局部熔融区域 ,其结果和大陆碰撞地球动力学模型的结果相一致。将大地电磁法应用于大陆动力学研究肯定能获得对形成大陆地壳的构造运动过程的新见解 ,尤其是在有“研究大陆动力学的天然实验室”之称的中国的构造运动活跃区域。
The magnetotelluric (MT) method provides images of the electrical resistivity of the crust and upper mantle from surface measurements of natural electric and magnetic fields. Developments in instrumentation and analysis techniques now permit MT data to be collected rapidly and interpreted in terms of two dimensional and three dimensional Earth models. Owing to the sensitivity of electrical resistivity to interconnected fluids, such as partial melt and water, magnetotelluric data can give information about the composition and rheology of the Earth that are complementary to that derived from seismic exploration. The MT method is now being applied to studies of continental dynamics in regions where tectonic processes are active. Magnetotelluric studies of the San Andreas Fault in the United States have revealed a correlation between segments of the fault that are seismically active and the resistivity of the fault zone in the brittle upper crust. Magnetotelluric data collected on the Tibetan Plateau have imaged a major zone of partial melting in the crust, that agrees well with geodynamic models for this continent continent collision. The continued application of the magnetotelluric method to continental dynamics will surely yield new insights into the tectonic processes that have formed the continental crust. This is especially true for the many tectonically active regions of China that provide a natural laboratory for the study of continental dynamics.
The magnetotelluric (MT) method provides images of the electrical resistivity of the crust and upper mantle from surface measurements of natural electric and magnetic fields. Developments in instrumentation and analysis techniques now permit MT data to be collected rapidly and interpreted in terms of two dimensional and three dimensional Earth models. Owing to the sensitivity of electrical resistivity to interconnected fluids, such as partial melt and water, magnetotelluric data can give information about the composition and rheology of the Earth that are complementary to that derived from seismic exploration. The MT method is now being applied to studies of continental dynamics in regions where tectonic processes are active. Magnetotelluric studies of the San Andreas Fault in the United States have revealed a correlation between segments of the fault that are seismically active and the resistivity of the fault zone in the brittle upper crust. Magnetotelluric data collected on the Tibetan Plateau have imaged a major zone of partial melting in the crust, that agrees well with geodynamic models for this continent continent collision. The continued application of the magnetotelluric method to continental dynamics will surely yield new insights into the tectonic processes that have formed the continental crust. This is especially true for the many tectonically active regions of China that provide a natural laboratory for the study of continental dynamics.
引文
[1] ARCHIEGE .Theelectricalresistivitylogasanaidindeterminingsomereservoircharacteristics[J].TransAmInstMinMetallPetEng,1942,146:5462.
[2] ANDERSONJL ,OSBORNERH ,PALMERDE .CataclasticrocksoftheSanGabrielfault anexpressionofdeformationatdeepercrustallevelsintheSanAndreasFault[J].Tectonophysics,1987,98:209251.
[3] BAHRK .Geologicalnoiseinmagnetotelluricdata:aclassificationofdistortiontypes[J].PhysEarthPlanetInt,1991,66:2438.
[4] BAKUNWH ,LINDHAG .TheParkfield,California,earthquakepredictionexperiment[J].Science,1985,229:619.
[5] BEDROSIANPA ,UNSWORTHMJ,WANGF .StructureoftheAltynTaghFaultandDaxueShanfrommagnetotelluricsurveys:impli cationsforfaultingassociatedwiththeriseoftheTibetanPlateau[J].Tectonics,2001,20:474486.
[6] BEDROSIANPA ,UNSWORTHMJ ,EGBERTGD .MagnetotelluricimagingofthecreepingsegmentoftheSanAndreasFaultnearHollister[J].GeophysResLett,2002,29:14.
[7] BERDICHEVSKYMN ,DMITRIEVVI .MagnetotelluricsintheContextoftheTheoryofIllPosedProblems[M ].Tulsa,Oklahoma,USA :SocExplorationGeophysicists,2002.
[8] BRASSEH ,LEZAETAP ,ROTHV ,etal.TheBolivianAltiplanoconductivityanomaly[J].JGeophysRes,2002,107:10.1029/2001JB000391.
[9] BROWNLD ,ZHAOW ,NELSONKD ,etal.Brightspots,structureandmagmatisminsouthernTibetfromINDEPTHseismicreflec tionprofiling[J].Science,1996,274:16881690.
[10] BYERLEEJ.Modelforepisodicflowofhigh pressurewaterinfaultzonesbeforeearthquakes[J].Geology,1993,21:303.
[11] CAGNIARDL .Basictheoryofthemagnetotelluricmethodofgeophysicalprospecting[J].Geophysics,1953,18:605635.
[12] CHENLB ,JONESJR ,WUAG ,etal.ElectricallyconductivecrustinSouthernTibetfromINDEPTHmagnetotelluricsurveying[J].Science,1996,274:16941696.
[13] EBERHART PhillipsD ,MICHAELA .Three dimensionalvelocitystructure,seismicityandfaultstructureintheParkfieldregion,CentralCalifornia[J].JGeophysRes,1993,98:1573715578.
[14] EGBERTGD .Robustmultiple stationmagnetotelluricdataprocessing[J \〗.GeophysicalJournalInternational,1997,130:475496.
[15] GAMBLETB ,GOUBAUWM ,CLARKEJ .Magnetotelluricswitharemotereference[J].Geophysics,1979,44:5368.
[16] GLOVERP ,HOLEMJ ,POUSJ.AmodifiedArchie sLawfortwoconductingphases[J].EarthPlanetSciLett,2000,180:369383.
[17] GROOMRW ,BAILEYRC .Decompositionofmagnetotelluricimpedancetensorsinthepresenceoflocalthree dimensionalgalvanicdistor tion[J].JGeophysRes,1989,94:19131925.
[18] INGHAMM ,BROWNC .AmagnetotelluricstudyoftheAlpineFault,NewZealand[J].GeophysJInt,1998,135:542552.
[19] JANSSENC ,HOFFMAN RotheA ,TAUBERS ,etal.Internalstructureofthepre cordilleranfaultsystem(Chile)—insightsfromstruc turalandgeophysicalobservations[J].JStructuralGeology,2002,24:123143.
[20] JONESAG .StaticshiftofMTdataandit’sremovalinasedimentarybasinenvironment[J].Geophysics,1988,53:967978.
[21] JONESAG ,FERGUSONIJ .TheelectricMoho[J].Nature,2001,409:33133.
[22] JONESAG ,CHAVEAD ,EGBERTGD ,etal.Acomparisonoftechniquesformagnetotelluricresponsefunctionestimates[J].JGeo physRes,1989,94:1420114213.
[23] KELLERGV .Rockandmineralproperties[A].NABIGHIANMN .ElectromagneticMethodsinAppliedGeophysics[M ].SocietyofExplorationGeophysicists,Tulsa,1987,1:2.
[24] LIS ,UNSWORTHMJ,BOOKERJR ,etal.PartialmeltoraqueousfluidsintheTibetancrust:constraintsfromINDETHmagnetotel luricdata[J].GeophysJInt,2003(inpress).
[25] MACKIERL ,LIVELYBROOKSDW ,MADDENTR ,etal.AmagnetotelluricinvestigationoftheSanAndreasFaultatCarrizoPlain,California[J].GeophysResLett,1997,24:18471850.
[26] MADDENT ,NELSONP .AdefenceofCagniard sMagnetotelluricMethod:ProjectNR 371401[Z].GeophysicalLab,Mas sachusettsInstituteofTechnology,1964.41.
[27] MARQUIS ,HYNDMAN .Geophysicalsupportforaqueousfluidsinthedeepcrust:seismicandelectricalrelationships[J].GJI ,1992,110:91.
[28] NADEAUR ,McEVILLYTV .SeismologicalstudiesatParkfieldV :Microearthquakesequencesasfault zonedrillingtargets[J].BulSeismolSocAm,1997,87:14631472.
[29] NELSONKD ,ZHAOW ,BROWNLD ,etal.PartiallymoltenmiddlecrustbeneathSouthernTibet:synthesisofProjectINDEPTHre sults[J].Science,1996,274:16841686.
[30] PALACKYGJ .Resistivitycharacteristicsofgeologictargets[A].NABIGHIANMN .Electromagn
[2] ANDERSONJL ,OSBORNERH ,PALMERDE .CataclasticrocksoftheSanGabrielfault anexpressionofdeformationatdeepercrustallevelsintheSanAndreasFault[J].Tectonophysics,1987,98:209251.
[3] BAHRK .Geologicalnoiseinmagnetotelluricdata:aclassificationofdistortiontypes[J].PhysEarthPlanetInt,1991,66:2438.
[4] BAKUNWH ,LINDHAG .TheParkfield,California,earthquakepredictionexperiment[J].Science,1985,229:619.
[5] BEDROSIANPA ,UNSWORTHMJ,WANGF .StructureoftheAltynTaghFaultandDaxueShanfrommagnetotelluricsurveys:impli cationsforfaultingassociatedwiththeriseoftheTibetanPlateau[J].Tectonics,2001,20:474486.
[6] BEDROSIANPA ,UNSWORTHMJ ,EGBERTGD .MagnetotelluricimagingofthecreepingsegmentoftheSanAndreasFaultnearHollister[J].GeophysResLett,2002,29:14.
[7] BERDICHEVSKYMN ,DMITRIEVVI .MagnetotelluricsintheContextoftheTheoryofIllPosedProblems[M ].Tulsa,Oklahoma,USA :SocExplorationGeophysicists,2002.
[8] BRASSEH ,LEZAETAP ,ROTHV ,etal.TheBolivianAltiplanoconductivityanomaly[J].JGeophysRes,2002,107:10.1029/2001JB000391.
[9] BROWNLD ,ZHAOW ,NELSONKD ,etal.Brightspots,structureandmagmatisminsouthernTibetfromINDEPTHseismicreflec tionprofiling[J].Science,1996,274:16881690.
[10] BYERLEEJ.Modelforepisodicflowofhigh pressurewaterinfaultzonesbeforeearthquakes[J].Geology,1993,21:303.
[11] CAGNIARDL .Basictheoryofthemagnetotelluricmethodofgeophysicalprospecting[J].Geophysics,1953,18:605635.
[12] CHENLB ,JONESJR ,WUAG ,etal.ElectricallyconductivecrustinSouthernTibetfromINDEPTHmagnetotelluricsurveying[J].Science,1996,274:16941696.
[13] EBERHART PhillipsD ,MICHAELA .Three dimensionalvelocitystructure,seismicityandfaultstructureintheParkfieldregion,CentralCalifornia[J].JGeophysRes,1993,98:1573715578.
[14] EGBERTGD .Robustmultiple stationmagnetotelluricdataprocessing[J \〗.GeophysicalJournalInternational,1997,130:475496.
[15] GAMBLETB ,GOUBAUWM ,CLARKEJ .Magnetotelluricswitharemotereference[J].Geophysics,1979,44:5368.
[16] GLOVERP ,HOLEMJ ,POUSJ.AmodifiedArchie sLawfortwoconductingphases[J].EarthPlanetSciLett,2000,180:369383.
[17] GROOMRW ,BAILEYRC .Decompositionofmagnetotelluricimpedancetensorsinthepresenceoflocalthree dimensionalgalvanicdistor tion[J].JGeophysRes,1989,94:19131925.
[18] INGHAMM ,BROWNC .AmagnetotelluricstudyoftheAlpineFault,NewZealand[J].GeophysJInt,1998,135:542552.
[19] JANSSENC ,HOFFMAN RotheA ,TAUBERS ,etal.Internalstructureofthepre cordilleranfaultsystem(Chile)—insightsfromstruc turalandgeophysicalobservations[J].JStructuralGeology,2002,24:123143.
[20] JONESAG .StaticshiftofMTdataandit’sremovalinasedimentarybasinenvironment[J].Geophysics,1988,53:967978.
[21] JONESAG ,FERGUSONIJ .TheelectricMoho[J].Nature,2001,409:33133.
[22] JONESAG ,CHAVEAD ,EGBERTGD ,etal.Acomparisonoftechniquesformagnetotelluricresponsefunctionestimates[J].JGeo physRes,1989,94:1420114213.
[23] KELLERGV .Rockandmineralproperties[A].NABIGHIANMN .ElectromagneticMethodsinAppliedGeophysics[M ].SocietyofExplorationGeophysicists,Tulsa,1987,1:2.
[24] LIS ,UNSWORTHMJ,BOOKERJR ,etal.PartialmeltoraqueousfluidsintheTibetancrust:constraintsfromINDETHmagnetotel luricdata[J].GeophysJInt,2003(inpress).
[25] MACKIERL ,LIVELYBROOKSDW ,MADDENTR ,etal.AmagnetotelluricinvestigationoftheSanAndreasFaultatCarrizoPlain,California[J].GeophysResLett,1997,24:18471850.
[26] MADDENT ,NELSONP .AdefenceofCagniard sMagnetotelluricMethod:ProjectNR 371401[Z].GeophysicalLab,Mas sachusettsInstituteofTechnology,1964.41.
[27] MARQUIS ,HYNDMAN .Geophysicalsupportforaqueousfluidsinthedeepcrust:seismicandelectricalrelationships[J].GJI ,1992,110:91.
[28] NADEAUR ,McEVILLYTV .SeismologicalstudiesatParkfieldV :Microearthquakesequencesasfault zonedrillingtargets[J].BulSeismolSocAm,1997,87:14631472.
[29] NELSONKD ,ZHAOW ,BROWNLD ,etal.PartiallymoltenmiddlecrustbeneathSouthernTibet:synthesisofProjectINDEPTHre sults[J].Science,1996,274:16841686.
[30] PALACKYGJ .Resistivitycharacteristicsofgeologictargets[A].NABIGHIANMN .Electromagn
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