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1.
INTRODUCTIONThepresenceofmagneticanomaliesoveroilandgasfieldshasbeenknownforseveraldecades,butitisonlyinrecentyearsthatthephenomenonhasbeencriticallyinvestigated .Themag neticcharacteristicsofsoilandsedimentarecloselyrelatedtosomegeochemicalprocesses,s…  相似文献   

2.
Association Rule Discovery and Its Applications   总被引:1,自引:0,他引:1  
INTRODUCTIONDataminingorknowledgediscoveryindatabase (KDD)hasinrecentyearsattractedalotofinterestinthedatabasecommunity .Theinterestismotivatedbythelargeamountofcomputerizeddatathatmanyorganizationsnowhavetheirbusi ness .Forinstance,supermarketsstoreelec…  相似文献   

3.
INTRODUCTIONTheSimaoregion (SWYunnan ,China) ,situatedbe tweentheAilaoshanbeltintheeastandtheLancangjiangzoneinthewest (Fig .1) ,isakeyareatochronologicallyconstrainlatePaleozoiccompressionaldeformationsandthusofprimein terestwhendiscussingtheplate tectonichi…  相似文献   

4.
INTRODUCTIONDrillingoptimizationisthelogicalprocessofanalyzingef fectsandinteractionsofdrillingvariablesthroughmathematicalmodelingtoachievemaximumdrillingefficiency .Thereductionofcoststhroughtheuseofoptimumtechniquesdoesnotstemfromfasterpenetrationr…  相似文献   

5.
INTRODUCTIONLargeareasofaridandsemiaridregionsoftheworldareaf fectedbywinderosion .Approximately 2 8.4%ofthisareaareaffectedbysevereandveryseverewinderosion (Katesetal.,1977) .InIraq ,thearidandsemiaridregionsrepresentnearly 75%ofthetotalland .5 0 %ofthislandissubjec…  相似文献   

6.
INTRODUCTIONItisanacknowledgedfactthataragonite,ahigh pressurepolymorphofCaCO3 ,occurswidelyasanindexmineralofhigh pressureandlow temperaturemetamorphism (glaucophaneschistfacies)withinthegeodynamiccontextofsubduction obductionandcontinentalcollision (Liou…  相似文献   

7.
INTRODUCTIONGroundwaterorfluidflowmodelinginfracturedrocksisacomplicatedtheoreticalandappliedtopic.Boththeoreticallyandoperationally ,itisimportantinmanyfieldssuchasgeologicalandhydrogeologicalengineering ,environmentalengineeringandpetroleumengineerin…  相似文献   

8.
INTRODUCTIONTheearthquakeactivityofafaultisthoughttobecon-strainedbythefaultcharacteristicsandtectonicstressfield(DengandZhan...  相似文献   

9.
INTRODUCTIONDespitethedevelopmentofelastic-plastic-viscousnumeri-calmethodfortheanalysisofslopes,traditionaltechniquesbasedon...  相似文献   

10.
INTRODUCTIONTheQinling Tongbai DabieorogenicbeltisacollisionalorogenicbeltbetweentheSino KoreanandYangtzecratons.Ultrahighpressure (UHP)andhighpressure (HP)metamor phicrockssuchascoesite bearingeclogitesarewidelydistribut edintheeasternendoftheorogenicbelt …  相似文献   

11.
INTRODUCTIONThequantitativereconstructionofpaleoclimatefactorsisthefocusofstudyonenvironmentinthepast ,andanef fectivetoolforthequantitativeresearchintothepaleocli mateisthetransformationofspore pollendata .ThemainperiodthusinvolvedwastheQuaternaryinste…  相似文献   

12.
ANENIGMA :EXTINCTIONOFDINOSAURThestratarecordthehistoryoftheearth .Everyscalecatas trophiceventallkeptsometraceinthestratum .Manyenigmascanberevealedthroughthecharactersofstrataandthefossilsinthestrata .TheextinctionofdinosaurisoneenigmahappenedintheCret…  相似文献   

13.
INTRODUCTIONThetemperaturestructureoftheearthinteriorhasapro foundscientificsignificanceforthestudyonthedynamicevolutionprocessoftheearth .Ingeneral,thecrustalandlithospherictem peraturefieldisdeterminedbytheequationofthermalconductionwiththesurfacehea…  相似文献   

14.
Fractal Correction of Well Logging Curves   总被引:6,自引:0,他引:6  
INTRODUCTIONBecausewellloggingmeasurementsgiveanaverageresultsnearbyconcurrentdepthpointsoftheprobesasshowninFig .1a ,wellloggingcurvedoesnotsupplytherealgeophysicalpropertiesatconcurrentdepthbutadisturbedresultofadjacentlayersandboreholeenvironment .Ho…  相似文献   

15.
INTRODUCTIONTheYujiapengtunnel,animportantpartofJuguiroadinZiguioftheThreeGorges,locatedonthesouthernbeachoftheYangtzeRiver,isveryimportanttotheThreeGorgesproject,totheeconomicdevelopmentofthisareaandfinallytothemigrationproject.Thistunnel,about 2kmlong ,…  相似文献   

16.
INTRODUCTIONThetheoreticalcalculationsofwatermigration ,whetherinanindividualfractureorinafissurenetwork ,haveallbeenbasedontheequationforviscousflowbetweenparallelplates.WilsonandWither spoon (1976 )firstaccomplishedahydraulicsimulationoffracturewatercross…  相似文献   

17.
INTRODUCTIONManystudiesofglobalchangesshowthatthehydrologicalcycleofacontinentalscalecanberelatedtoclimaticchanges(Andersonetal.,2 0 0 1;KarenandDara,2 0 0 1;MichaelandMichael,1999;Hugoetal.,1996 ;Larryetal.,1996 ) .Cur rentdistributionpatternsofdeuteriumandoxygen 18concen …  相似文献   

18.
INTRODUCTIONANDBRIEFGEOLOGICALDESCRIP┐TIONSTheUpperOrdovicianmarinevolcanicrocksonthenorthmarginofQaidamhavebeenrepeatedlydis...  相似文献   

19.
INTRODUCTIONOneofthemostimportanttopicsinearthquakegeotech-nicalengineeringistheaseismaticdesignofearth-retainingstructures(H...  相似文献   

20.
INTRODUCTIONAmodelmethod ,createdinthescientificresearch ,isusedtorepresentanobject.Suchamodelismodifiedandimprovedinor dertoapproacharealresearchobject.Thiskindofmodel,widelyandeffectivelyusedinthepresentresearchintoacomplexsystem ,mayhelpustodescribeand…  相似文献   

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