钻孔雷达探测地下裂缝

,,(,130026):,,,,,,,,30m,,,:;;;:V443.2:A:(40474042):(19662),,,,,,Tel:[phone]SubsurfaceFracturesDetectionbyBoreholeRadarLIUSi2xin,ZENGZhao2fa,XUBo(CollegeofGeoExplorationScienceandTechnology,JilinUniversity,Changchun130026,China)Abstract:BoreholeradarisaspecialmodeofGroundPenetratingRadar.Ithasseveraldistinguishedfeaturesfromsurfaceradar.Forexamples,bymeansofboreholeaccesstoregionsbelowthesurface,theantennascanbelocatedrelativelyclosetotheanomaliesortargetstobemeasured,resultinginmoreprecisetargetsresponseindeepsubsurfaceapplications.TheexperimentalsiteislocatedonthetopofagranitehillwestofBeijing.Thereisagroupofboreholesintersectedbymanyfractures;bothsingle-holeandcross-holemeasurementswerecarriedout.Themeasureddataareprocessedandinterpreted.Theradialdetectingrangeismorethan30metersatthissite.Thesubsurfacefracturedistributioncanbeimagedveryclearly.Manyfracturescanbeseen,andtheirdistancefromboreholeandtheirdipan2glecanbedetermined.Theazimuthdeterminationsforthesefracturesarepossibleinsomesituations.Itisconcludedthattheboreholeradarisaneffectivetoolforsubsurfaceimaging.Keywords:boreholeradar;antenna;fracture;dataprocessing,[13],:-VRP,,,[4,5],,,,135()Vol135Sup120057JournalofJilinUniversity(EarthScienceEdition)July2005,,-,1,,,,360,,,,360,,,,,,,1Fig11Antennaconfigurationforsingleholemeasur-ementandreflectioncharacteristic2,FR,AE1,AE2,AE3,AE4,2FR,AE1,AE3,AE4FRAE2AE13(a)2Fig12Theexperimentalsite3,,(AGC)AE13(b),3AE1()()Fig13BoreholeAE1radarprofilesbefore(right)andafter(left)dataprocessing921,,:,01128möns,30m4-4,,,,,,,5,4Fig14Interpretedfracturesfromsingle-holeme-asurement5Fig15Spatialdistributionoffractures,,,,5,5060,,,,,,,,,30m031()35,,,,40m,,,FR,FR5675,AE1AE3AE4,6,65Fig16Possible3Ddistributionofafracture#5FR5,AE4,,,7171904412,5257155218,63575719,,,5,,,,,,,:[1]OlssonLF,ForslundO,LundmarkL,etal.Boreho2leradarappliedtothecharacterizationofhydraulicallyconductivefracturezonesincrystallinerock[J].Geophys.Prospecting,1992,40:1092142.[2]Sandberg,EricV,OlssonOlleL,FalkLarsR.Com2binedinterpretationoffracturezonesincrystallinerockusingsingle2hole,crossholetomographyanddirectionalborehole-radardata[J].TheLogAnalyst,1991,32:1082119.[3]SatoM,ThierbachR.Analysisofaboreholeradarincross-holemode[J].IEEETrans.Geosci.RemoteSensing,1991,29:8992904.[4]AndrewBinley,GiorgioCassiani,RoyMiddlrton.Vadosezoneflowmodelparameterisationusingcross2boreholeradarandresistivityimaging[J].JournalofHydrology,2002,267(3-4):1472159.[5]AndrewBinley,PeterWinship,JaredWestL,Mag2delinePokar,andRoyMiddlrton.Seasonalvariationofmoisturecontentinunsaturatedsandstoneinferredfromboreholeradarandresistivityprofiles[J].JournalofHydrology,2002,267(324):1602172.131,,: