简介:Theproblemsoftheearth'sgravityfields'visualizationarebothfocusandpuzzlecurrently.Aimingatmultiresolutionrendering,modelingoftheEarth'sgravityfields'dataisdiscussedinthepaperbyusingLODalgorithmbasedonQuadTree.First,thispaperemployedthemethodofLODbasedonQuadTreetodivideuptheregionalgravityanomalydata,introducedthecombinednodeevaluationsystemthatwascomposedofviewpointrelatedandroughnessrelatedsystems,andtheneliminatedtheT-cracksthatappearedamongthegravityanomalydatagridswithdifferentresolutions.Thetestresultsdemonstratedthatthegravityanomalydatagrids'renderingeffectswereliving,andthecomputationalpowerwaslow.Therefore,theproposedalgorithmwasasuitablemethodformodelingthegravityanomalydataandhaspotentialapplicationsinvisualizationoftheearth'sgravityfields.
简介:ResearchonnonlinearR/SmethodanditspplicationinearthquakepredictionBi-QuanWANG(王碧泉);Han-MingHUANG(黄汉明);Hong-ShunFAN(范洪顺);Chuen...
简介:EstimatedGreen'sfunction(EGF)betweenstationshasbeenextractedfromambientseismicnoise,directsurfacewaveandcodawaves.Itisalsoconfirmedbylaboratoryexperimentsonultrasonicsandtheoreticalderivationsassumingdiffusivewavefield,equi-partitionofmodesorrandomsourcesonanenclosedsurface.Thismethodprovidesanewapproachtostudythecrustandmantlestructureatregionalscale,continentalscaleandglobalscale.Followingtheachievementswithseismometerrecords,therecordsofinfrasonicstation,hydrophoneandmicrophonewerealsousedtoobtaintheEGFsofdifferentwavefields.Sincesuperconductinggravimeterisabetterlongperiodinstrumentthanregularseismometer,EGFatlongerperiodisexpectedtobeobtainedwiththecrosscorrelationofgravitydata.Inthispaper,wewillshowtheEGFsextractedbycross-correlationsbetweenthesuperconductinggravimetersandtheseismometers.Boththetraveltimesanddispersioncurvesobtainedfromdifferentdatatypesareconsistent.Theresultshowsthatitispossibletoretrievethedeepstructurebythecrosscorrelationofgravitydata.
简介:Thesimplelinearrelationshipbetweenclear-skyplanetaryandsurfacealbedocanbeadoptedforcertainaccuracy.Therearedifferentparameterizationschemesofatmosphericcorrectionfordifferentretrievalmodels.Inthispaper,severalrepresentativeretrievalmodelsarecomparedandtestedwithobservationaldatafromHEIhebasinFieldExperiment(HEIFE)inwesternChina.Someevaluationsandsuggestionsonimprovementareproposedformodelswhichwouldbemoreapplicabletoplateauandaridareas.
简介:EstimationofThomsen'sanisotropicparametersisveryimportantforaccuratetime-to-depthconversionanddepthmigrationdataprocessing.Comparedwithothermethods,itismucheasierandmorereliabletoestimateanisotropicparametersthatarerequiredforsurfaceseismicdepthimagingfromverticalseismicprofile(VSP)data,becausethefirstarrivalsofVSPdatacanbepickedwithmuchhigheraccuracy.Inthisstudy,wedevelopedamethodforestimatingThomsen'sP-waveanisotropicparametersinVTImediausingthefirstarrivalsfromwalkawayVSPdata.Modelfirst-arrivaltraveltimesarecalculatedonthebasisofthenear-offsetnormalmoveoutcorrectionvelocityinVTImediaandraytracingusingThomsen'sP-wavevelocityapproximation.Then,theanisotropicparameters0andearedeterminedbyminimizingthedifferencebetweenthecalculatedandobservedtraveltimesforthenearandfaroffsets.Numericalforwardmodeling,usingtheproposedmethodindicatesthaterrorsbetweentheestimatedandmeasuredanisotropicparametersaresmall.Usingfielddatafromaneight-azimuthwalkawayVSPinTarimBasin,weestimatedtheparameters0andeandbuiltananisotropicdepth-velocitymodelforprestackdepthmigrationprocessingofsurface3Dseismicdata.Theresultsshowimprovementinimagingthecarbonatereservoirsandminimizingthedeptherrorsofthegeologicaltargets.
简介:Inthefirsthalfyearof2018,therewerechangesinChina'seconomic,industrialstructureandthechangesingovernment'spolicyonlandandmineralresources.China'sgeologicalexplorationiscontinuedtomaintainatrendofthegrowth.Thefundinvestmentingeologicalexplorationdeclinedandtheimpetusforinvestmentininitialexplorationwasinsufficient.Theminingmarketshowedagooddevelopmenttrendandthesocialinvestmentdepictedaslightrise.Inthefirsthalfoftheyear,theinvestmentsinhydrogeologicexploration,environmentalgeologyexplorationandgeologicaldisasterinvestigationincreasedontheyear-onyearbasis.
简介:ByusingobservedCHAMPorbitephemeredesandMSISE-90dryairmodelandregardingtheearthasasphereandanellipsoidrespectively,phasedelaysaresimulatedandthesimulateddataareretrievedunderdifferentschemes.Thecomparisonbetweentheinvertedtemperatureprofilesandthemodeltemperatureprofilesshowsthatbyinvertingobserveddata,wewillgettemperatureresultswithlargeerrorsiftheeffectofEarth'soblatenessisomitted.Thecorrectionmethodisprovedtobeeffectivebecausethetemperatureerrorsdecreasedobviouslywiththismethod.
简介:Itispresentedthatthereisapumpingeffectatitsbaseinthedevelopmentprocessofacumulus.Inthestrongeststageofcumulusdevelopment,thepumpingismainlyproducedbythebuoyanceatthebase,andmaybetakenasthefirstapproximationoftheascendingspeedatthebase.Theresultsofnumericalcalculationsandsimulationsoffourobservedradarechoesshowthatasthefirstapproximation,theheightofair-masscumulusmaybesimulatedbyHaltinermodelintheabsenceofob-servedascendingspeedsatthebase,andtheHaltinermodelcanbecharacterizedbythesensitivityofthecumulusdevelopmenttothevirtualtemperatureexcessoverenvironmentatthebase.
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简介:AstatisticalanalysisoftectonicenvironmentforM≥6.0strongearthquakesinChina'scontinentsincethebeginningofrecordedhistoryisperformedbasedonthedataofactivefaultsstudiedduringlast10yearsandresultofcompilationofthefourthversionoftheMapofSeismicRegionalizationofChinaforEarthquakeProtection.Tectonictypesofseismicsourcesofstrongearthquakesinallseismicregionsandthemovementmodesofseismogenicstructuresarediscussed.Meanwhile,ananalysisoflengthsofsurfacerupturezonesproducedbyalltypesofearthquakes,orientationsoflongaxesofmeizoseismalareas,regionaltectonicstressfieldsinseismicsourceregionsforstrongearthquakes,geophysicalfields(gravityanomaly,highconductivitylayeranomaly,andterrestrialheatflowdensity),andrecentverticalcrustaldeformationfieldshavebeencarriedout.
简介:TheeasternandwesternfrontsofplatemovementinTaiwanIslandandTibetanPlateaurespectivelyarethetwomajorsourcesoftectonicforceforthemorphogensisduringQuaternaryinChina'stropics.SevenexamplesofgeomorphologicaleffectsofplatemovementareenumeratedtodiscussthedifferentiationoftectoniclandformsinspaceandtimeduringQuaternary.ThetectonicmovementtendstobemoreactivesincemiddlePleistocene.Somephenomenasuchasthearc-shapemountainsystems,volcanismandcrustaldeformationimplythatthejuncturezoneofeasternandwesterntectonicforcesislocatedatabout110°E.