简介：AseismometerdataacquisitionunithasbeenusedintheChangpingseismicstationtorecordtheoutputofastrainmeter.Theoutputofastrainmeterwassampledatarateof100/secbyseismometeracquisitionfromtheoriginalrateof1perminute.Plentyofhighfrequencysampleddatawasrecorded.Theminutevaluecurvecalculatedfromtheseismometeracquisitionareconsistentwiththatoftheoriginaldatasampledbythestrainacquisitionsystem.Morecompletewaveformswererecordedwithahighersamplingrate,andseismicphaseparameterscalculatedbyusinghighersamplingratestrainseismicwavesarealsoinconsistencywiththeresultsofitspredecessors.SpectraofthestrainseismicwavesarecomparedwiththatofseismicwavesrecordedbyaseismometerintheShisanlingseismicstation,andtheirtrendsarealmostthesame.Besides,somelowerfrequencycomponentsstillexistinstrainseismicwaves.

简介：ＳｅｖｅｒａｌｑｕｅｓｔｉｏｎｓａｂｏｕｔｕｓｉｎｇｎａｔｉｏｎａｌｌｅｇａｌｍｅｔｒｏｌｏｇｉｃａｌｕｎｉｔｉｎｓｅｉｓｍｏｌｏｇｉｃａｌｐｅｒｉｏｄｉｃａｌｓＹｉ－ＪｕｎＦＥＮＧ（冯义钧），Ｘｕｅ－ＬｉａｎｇＬＩ（李学良）ａｎｄＣｈｅｎｇ－ＹｅＸ...

简介：Organicreefs,thetargetsofdeep-waterpetroleumexploration,developedwidelyinXishaarea.However,thereareconcealedigneousrocksundersea,towhichorganicrockshavenearlyequalwaveimpedance.Sotheigneousrockshavebecomeinterferenceforfutureexplorationbyhavingsimilarseismicreflectioncharacteristics.Yet,thedensityandmagnetismoforganicreefsareverydifferentfromigneousrocks.Ithasobviousadvantagestoidentifyorganicreefsandigneousrocksbygravityandmagneticdata.Atfirst,frequencydecompositionwasappliedtothefree-airgravityanomalyinXishaareatoobtainthe2Dsubdivisionofthegravityanomalyandmagneticanomalyintheverticaldirection.Thus,thedistributionofigneousrocksinthehorizontaldirectioncanbeacquiredaccordingtohigh-frequencyfield,low-frequencyfield,anditsphysicalproperties.Then,3Dforwardmodelingofgravitationalfieldwascarriedouttoestablishthedensitymodelofthisareabyreferencetophysicalpropertiesofrocksbasedonformerresearches.Furthermore,3Dinversionofgravityanomalybygeneticalgorithmmethodofthegraphicprocessingunit(GPU)parallelprocessinginXishatargetareawasapplied,and3Ddensitystructureofthisareawasobtained.Bythisway,wecanconfinetheigneousrockstothecertaindepthaccordingtothedensityoftheigneousrocks.Thefrequencydecompositionand3DinversionofgravityanomalybygeneticalgorithmmethodoftheGPUparallelprocessingprovedtobeausefulmethodforrecognizingigneousrockstoits3Dgeologicalposition.Soorganicreefsandigneousrockscanbeidentified,whichprovideaprescientinformationforfurtherexploration.