简介：BasedonthesolutionsoftheGreen'sfunctionforasaturatedporousmediumobtainedbytheauthors,andusingtransformationofaxisymmetriccoordinates,Sommerfeldintegralsandsuperpositionoftheinfluencefieldonafreesurface,theauthorshaveobtaineddisplacementsolutionsofasaturatedporousmediumsubjectedtoatorsionalforceinahalf-space.Therelationshipcurvesofthedisplacementsolutionsandvariousparameters(permeability,frequency,etc.)underactionofaunitoftorquearealsogiveninthispaper.TheresultsareconsistentwithpreviousReissner'ssolutions,whereatwo-phasemediumdecaystoasingle-phasemedium.Thesolutionisusefulinsolvingrelevantdynamicproblemsofatwophasesaturatedmediuminengineering.

简介：OnApril25,2015,aM_S8.1earthquakeoccurredinNepal.IntheTibetareaofChina,thisearthquakecausedheavycasualtiesanddamagetohousing,roads,communications,otherlifelineengineering,waterconservancyandotherinfrastructure.Thispaperintroducesthebasicsituationoftheearthquake,andbasedontheinvestigationandassessmentofseismicintensity,thedamageofthedisasterareaisanalyzed,andbuildingtypesanddamagetothelifelinesystemsandvariousindustriesaregiven.Throughtheanalysisofthecharacteristicsoftheearthquakedisaster,thispaperpointsouttheexistingproblemsinseismicfortification,andfinallyputsforwardproposalsforthepreventionandcontrolofearthquakegeologicaldisasters,scientificplanningfortherestorationandreconstruction,strengtheningearthquakepreventionanddisasterreductionpropaganda,improvingtheawarenessofearthquakepreparednessintheagriculturalandpastoralareas,strengtheningtheguidanceandsupervisionofhousingconstructioninruralareastoreducethecasualtiesandlosses,andpromotingtheharmoniousdevelopmentofeconomyinTibet.

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简介：2006年7月4日11时56分在河北省文安县（东经116．3°、北纬38．9°）发生5．1级地震，北京市、天津市、河北和山西均有震感。本文作者在地震现场调查的基础上，对比分析了我国其他大陆地区5级左右地震的人员伤亡和震害情况，探讨了此次地震未造成人员伤亡和较大损失的原因。

简介：１９９５年７月２２日０６时４４分于北纬３６°２３＇，东经１０３°１３＇甘肃省永登县七山乡发生Ｍｓ５．８级地震。该地震震中距兰州市中心仅９０ｋｍ，并发生在甘肃青海两省前兆台网密度较大地区。本文将对震前甘肃局对这次地震的预报情况，甘肃中东部及其毗邻的青海东北部地区前兆异常显示及其时空分布特征作一介绍。

简介：Inordertodeterminethedegreeofreturning-to-zerooftemperaturesofdeformedcalcite,aseriesofrock-breakingexperimentsweredesignedtotestcalcite-richlimestonesamplesunderfixedconfiningpressuresanddifferenttemperatures.Theconsolidateddeformedsamplesintheirinitialstatewereobservedunderamicroscopeandthemicroscopicindicatorsindifferentzero-returningstateswereputforward,thusprovidingamicroscopicfoundationforevaluationofreliabilityofdatingvaluesofdeformationincalcite.Atlast,thecorrectionofdatingvaluesofdeformationforsampleswhosetemperaturehasnotyetreturnedtozeroisdiscussed.

简介：Inthispaper,basedonGansuDigitalSeismicNetworkdatasince1990,wecalculatedb-valueand⊿b-valueoftheneighborhoodareabeforethe2013Minxian-ZhangxianM_S6.6,earthquake.Theresultsshowthattheearthquakeoccurredatthemarginofthesignificantlylowerb-valueareainsoutheastofGansuandbeforetheearthquaketheneighborhoodareahadanobviouslyabnormal⊿b-value.Fromtheearthquakeandthespatialdistributionoflowb-value,theregionstillhasthepossibilityofgeneratingdangerousstrongearthquakes.

简介：ＩｎｔｅｒｐｒｅｔａｔｉｏｎｏｆＳｗａｖｅｄａｔａｆｒｏｍＴａｉ′ａｎＸｉｎｚｈｏｕＤＳＳｐｒｏｆｉｌｅａｎｄｉｔｓｒｅｌａｔｉｏｎｓｈｉｐｗｉｔｈＸｉｎｇｔａｉｅａｒｔｈｑｕａｋｅｓＳＯＮＧＹＡＮＳＯＮＧ（宋松岩）１）ＸＵＥＳＯＮＧＺＨＯ...

简介：2014年11月15日,在甘肃省白银市景泰县发生MS4.7地震,震源深度10km。在震中附近200km以内,甘肃省地震局共安装架设有14台各类形变观测仪器。本文通过对这些形变观测仪产出的分钟值观测资料做小波分析发现,在地震前1个月内共有11台(套)形变观测仪记录到了异常变化。其中:SSY、TJ、DSQ、SSQ型观测仪记录到异常的同步性非常好;CZB型观测仪记录到的异常比较乱,没有固定的规律。通过对这些异常变化的总结能够为地震预测提供一定的判断依据。

简介：汶川Ms8．0级地震发生在青藏高原东缘著名的龙门山断裂带上，造成了中央断裂和前山断裂共约330kin的地震地表破裂带。初步研究表明，龙门山断裂带上大震复发可能属特征地震模式。结合龙门山断裂带的地震地质情况和汶川地震地表破裂带的基本参数综合分析，本文从地质学、地震学和GPS数据分析三个方面评估了龙门山断裂带的大震复发周期。结果表明，上述三种方法获得的龙门山断裂带Ms8．0级地震的复发间隔分别为：3185a、170（02264a和4310a，平均为3000a左右：Ms7．5级地震的平均复发间隔为1000a左右；Ms7．0级地震的平均复发间隔为500a左右。这些结果与其他学者的研究结果相比，相差不多，基本反映了龙门山断裂带的地震能量水平和累积速度。

简介：本文分析了台湾地区近期55级以上地震的时空图象,发现台湾地区从93年开始55级以上地震逐渐形成一条中强地震共轭条带,其中主条带长仅300公里左右。强震条带形成后,1999年9月21日在主条带的西南段1/3处条带的西侧边缘南投发生了76级地震。南投地震后,55级以上地震条带仍然存在,2002年3月31日在共轭条带交汇处附近苏沃海外发生了75级地震。在共轭条带内相隔两年半时间里发生两次7级以上地震实属罕见

简介：Ｃｏｍｐｌｅｘ　ｔｉｍｅ－ｓｐａｃｅ　ｓｐｒｅａｄｉｎｇ　ａｎｄ　ｆｏｃａｌ　ｍｅｃｈａｎｉｓｍ　ｏｆ　ｔｈｅ　１９８９　Ｂａｔａｎｇ　ｅａｒｔｈｑｕａｋｅ　ｓｗａｒｍ　（Ｍ＿ｓ＝６．７）（程万正）（陈天长）Ｃｏｍｐｌｅｘｔｉｍｅ－ｓｐａｃｅｓｐｒｅ...

简介：BasedonthewaveformdataobservedbytheregionalseismicnetworkofGansuProvince,wecalculatedtheapparentstressof422earthquakeswithM_L≥2.0occurringinthesurroundingareaoftheMinxianearthquakefromJanuary2010toJuly2014andobtainedthetemporalandspatialvariationofapparentstressbeforeandaftertheMinxianearthquake.Resultsshowthat(1)thehighvalueofapparentstressofearthquakeswithM_L≥4.0wasconcentratedintheepicenterareabeforetheMinxianearthquakewhilethatofearthquakeswithM_L<4.0wasnot;(2)ApparentstressaroundtheepicenterareashowedanobviousincreasingprocessbeforetheMinxianearthquakeandtheincreasingprocesshascontinuedafterthemainshock,whichmeansthatthisstudyareaisstillinthedangerofstrongearthquakes.

简介：应用ＣＤＳＮ台网兰州数字台的记录和中法合作建立的朗索数字台的记录，研究了１９９５年７月２２日甘肃永登５．８级地震和１９９６年６月１日天祝－古浪５．４级地震前台剪切波分裂的特征。结果表明，在永登地震前大约１年的时间延迟和偏振方向很快恢复。因此，可以认为，此次地震前ＮＷ向，地震后剪切波分裂时间延迟和偏振方向很快恢复。因此，可以认为，此次地震前Ｓ波分裂方向的前兆特征是明显的。对于天祝－古浪５．４级地震，

简介：ThemodeserialsoftheEarth'sfreeoscillationprovidesomeimportantinformationontheEarth'sdeepstructureandsuperconductinggravimeters(SG)caninvestigatethephenomenaoftheEarth'sfreeoscillationswithhighaccuracy.ThegreatSumatra-AndamanearthquakefullyexcitedtheEarth'sfreeoscillationsandthesesignalswereperfectlyrecordedbyfivesuperconductinggravimetersintheglobe.Afterthepre-treatmentandspectralanalysisontheSGobservationdata,weobtainedtheexperimentedmodeserialsoftheEarth'sfreeoscillationsconsistingof147modeswithGGPstationdata.TheseobservedmodeswerethemselvessomenewimportantdataforthestudyoftheEarth'sdeepstructure.Onthebasisofthediscussionsonsomecheckedinner-core-sensitivemodes,wedistinguishedthreelayersfromtheinnercore,andtheboundaryoftheupperlayerwascompatiblewiththeformerlyknowntransitionzoneintheinnercorebasedonseismicbodywavesandsupportedthattherewerethehemisphericalvariationandverylowershearvelocityzoneinthelowerinnercore.

简介：TheHori’sinversemethodbasedonspectraldecompositionwasappliedtoestimatecoseismicslipdistributionontheruptureplaneofthe14November2001MS8.1KunlunearthquakebasedonGPSsurveyresults.TheinversionresultshowsthatthesixslidingmodelscanbeconstrainedbythecoseismicGPSdata.Theestablishedslipsmainlyconcentratedalongtheeasternsegmentofthefaultrupture,andthemaximummagnitudeisabout7m.Slipontheeasternsegmentofthefaultrupturerepresentsaspurelyleft-lateralstrike-slip.Sliponthewesternsegmentoftheseismicrupturerepresentsasmainlydip-slipwiththemaximumdip-slipabout1m.Totalpredictedscalarseismicmomentis5.196×1020N?m.Ourresultsconstrainedbygeodeticdataareconsistentwithseismologicalresults.

简介：本文通过对漳州开发区7号山体硐室大爆破振动速度、加速度的测试及数据的初步分析,阐述了爆破地震波衰减规律及其影响因素。并引入平均衰减指数的概念,对开发区当地以后众多的大、中型爆破抗震的安全设计提供有益的依据。

简介：2015年7月3日新疆皮山Ms6．5级地震灾区地处塔里木盆地南缘，该地自然条件恶劣，经济极为落后，灾区农村的民房除了抗震安居工程建设的房屋外，还有大量抗震性能较差的民居，在地震中受损严重，经济损失较大。灾区大部分位于山前溢出带，地下水位浅、地基土层软弱等场地条件对地震动有放大作用，震害影响范围较大。灾后重建中应继续加大安居富民工程的经费投入力度。灾区北部人口密集，地基土层软弱，工程地质条件差，建议在今后的安居富民建设中加强地基处理。

简介：IntroductionRegionalseismicitytriggeredbybigearthquakesaswellasattershocksinsourcezonecouldbedetectedduetothehighseismicmonitoringcapabilitytoday(Anderson,etal,1994;Bodin,Gomberg,1994;Caskey,Wesnousky,1997;Deng,Sykes,1996;Hill,etal,1993;King,etal,19...

简介：ThisstudyproposesaGreen’sfunction,anessentialrepresentationofwater-saturatedgroundundermovingexcitation,tosimulategroundbornevibrationfromtrains.First,generalsolutionstothegoverningequationsofporoelasticmediumarederivedbymeansofintegraltransform.Secondly,thetransmissionandreflectionmatrixapproachisusedtoformulatetherelationshipbetweendisplacementandstressofthestratifiedground,whichresultsinthematrixoftheGreen’sfunction.ThentheGreen’sfunctioniscombinedintoatrain-track-groundmodel,andisverifiedbytypicalexamplesandafieldtest.Additionalsimulationsshowthatthecomputedgroundvibrationattenuatesfasterintheimmediatevicinityofthetrackthaninthesurroundingarea.Thewavelengthofwheel-railunevennesshasanotableeffectoncomputeddisplacementandporepressure.Thevariationofvibrationintensitywiththedepthofgroundissignificantlyinfluencedbythelayeringofthestratasoil.WhenthetrainspeedisequaltothevelocityoftheRayleighwave,theMachconeappearsinthesimulatedwavefield.TheproposedGreen’sfunctionisanappropriaterepresentationforalayeredgroundwithshallowgroundwatertable,andwillbehelpfultounderstandthedynamicresponsesofthegroundtocomplicatedmovingexcitation.