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144 个结果
  • 简介:根据全国强地震目录,选取1900年至2010年发生在内蒙古、甘肃、宁夏和青海交界地区的历史及现代中强地震作为研究对象,分析其时空分布特点,试图论证上述地区中强地震之间的相关性。研究结果表明,蒙甘宁青地区中强地震之间整体上存在一定的相关性,而在划定的不同时空范围内,这种相关性表现不一。

  • 标签: 蒙甘宁青地区 历史及现代中强地震 地震关联
  • 简介:TheJuly3,2015PishanM_S6.5earthquakeoccurredintheintersectionareaoftheTarimblockandWestKunlunblockwherethemoderate-strongearthquakeshavebecomeactiveinrecentyears.Thispaperhasstudiedtheseismicityparametersoftheearthquakesequencessuchastheb-valueinthePishanregionanditsvicinity.Inaddition,wealsorelocatedtheaftershocksofthePishanM_S6.5earthquakeusingtheseismicphasereportbythedouble-differencemethod.ThetemporalandspatialvariationcharacteristicsofthePishanearthquakesequenceintherupturezoneareanalyzed.Thestudyisofgreatsignificanceintheseismichazardassessmentinthisregion.

  • 标签: 地震活动性 地震危险性评价 迁移 地震序列 中强地震 地震发生
  • 简介:BodywaveforminversionforthesourceprocesoftheFebruary3,1996Lijiang,YunnanearthquakeYANGXU)(徐扬)MASAYUKIKIKUCHI2)(菊地正幸)YOU-JIN...

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  • 简介:TheYutianearthquakewithM_S7.3happenedonFebruary12,2014.Theprecursormonitoringabilityisweakinthatarea.Wefoundtendencyanomaliesandmiddle-andshort-termanomaliesfrommetalpendulumtiltmeasurementsinHotanseismicstationbeforetheearthquake.AndwealsocomparedtheanomalieswiththatoftheM_S7.3YutianearthquakeonMarch21,2008.Thetendencyanomaliesmeasuredbythemetalpendulumtiltmeterappearedsince2012astiltingeastward.Whilethemiddle-andshort-termanomalieswerecharacterizedbyacceleration,pauseandrapidchangeoftiltrateintwodirections.Thetendencyanomaliesofmetalpendulumtiltrecordsarethesamebeforethetwoearthquakes.Theybothhappenedintheeastdirection.However,therearedifferencesinduration,characteristicandearthquakeintervalsforthemiddle-andshort-termanomalies.

  • 标签: 中短期异常 地震台 变形 趋势异常 异常持续时间 地震间隔时间
  • 简介:应用从属函数法分析了1988年1月-2007年9月华清4^#泉的水氡资料,共提取出6次中期异常。其中前4次异常在异常结束后的8~24个月对应了发生在南北地震带、青藏高原北部的肘≥7.3级远场强震,第5次为无震异常,第6次异常正在持续发展。对异常特征及其与地震的对应关系作了讨论,给出了远场强震时间预测的指标,并依据第6次异常开始出现的时间,对未来远场强震发生的时间段进行了中期预测。

  • 标签: 水氡 从属函数 远场强震 异常
  • 简介:从异年倍九法(或称异年倍九律)讨论了华北7级以上大震发生日期之间的关系。这种关系对今后类似季节预测大震的发生日期有一定的参考作用。

  • 标签: 华北地区 异年倍九律 发震日期 地震预测
  • 简介:边界条件能显著地强烈地震下面影响斜坡行为。为了为有限元素(FE)评估边界条件的重要性,一张饮料桌子的模拟在斜坡反应上试验,一验证三维(3D)非线性的FE模型被介绍,并且数字、试验性的结果被比较。为那个目的,基于公开源码的计算站台OpenSees,柔韧的图形的用户接口SlopeSAR被采用,它简化努力集中的预处理和processing以后阶段。网孔决定效果也被探讨。参量的研究被执行在在结束脸包含边界程度和边界条件的三种类型的FE模型上评估边界条件的影响。通常,边界程度的变化生产不一致的斜坡变丑。为二张结束脸,修理y方向排水量不是适当的模仿饮料桌子实验,结束墙僵硬、不平。另外,3D的长度的影响倾斜最高的脸和处于二之间的差别的一个重要角色结束边界条件打的斜坡戏的宽度面对(修理y方向排水量并且修理(y,z)方向排水量)。总的来说,这研究加亮对模拟和试验性的结果之间的比较的评价竟然与到期的考虑被执行到边界的效果,这调节。

  • 标签: 边界条件 条件模拟 边坡变形 地震反应试验 三维 有限元模型
  • 简介:Inthispaper,wedeterminedanearthquakesequencelocationintheXingfengjiangareafromJune,2007toJuly,2014andthe3DP-wavevelocitystructurebyasimultaneousinversionmethod.Onthatbasis,westudiedtheoccurrencefeaturesofactivetectonicsandtheearthquakesourcemechanism.Theresultsshowthatthereservoirfracturesystemhasatendencytoincreasewithgradualdepthfromsoutheasttonorthwest,consistentwithgravitationalfieldresearchresults.Thereare4highvelocityzones(HVZ)underthedepthofthe7km-12kmcrustbetweentheXinfengjiangReservoirdamandXichangDistrict,Dongyuan.ThemaxvelocityofthebiggestHVZwhichisunderXichangis6.3km/s.Underthereservoirdamthereisastrongtectonicdeformationzone,asthecenterexitRenzishifault(F2),Nanshan-Aotoufaults(F4),Heyuanfault(F1)andShijiao-Xingang-Baitianfault(F5),7earthquakeswithML≥5.0(includingM6.1inMarch,1962)occurredatthehighgradientzoneoftheHVZⅢandHVZⅣedgewhichhasbeenunderthereservoirdamsince1960,withrelativityenergyreleasingmorethoroughly.ModerateseismicactivityoccurredattheHVZⅠedgewhichhasbeenunderXichangsince2012,andisadangerzoneforM5.0earthquakesinthefuture.

  • 标签: P-WAVE velocity STRUCTURE Active TECTONICS SIMULTANEOUS
  • 简介:Athree-dimensionalrigidbodyontheshapeofaparallelepipedismodelledinordertorockonasideoravertexofthebase,inordertoevaluatetheseismicresponseofrigidblockslyingonahorizontalsupport.Thecenterofmassofthebodyisconsideredaseccentricwithrespecttoitsgeometriccenter.Asseismicinput,threeItalianrecordedaccelerograms,withdifferentspectralcontent,areused.Thestudyismainlyconductedtohighlightthedifferencesbetweentheseismicresponseof2Dand3Dmodelsofrigidblocks,withtheaimtounderstandif,insomecases,theuseofthe3Dmodelofrigidblockisrequiredtoobtainsaferresults.Infact,theoutcomesshowthatinsomerangesofthegeometricalandmechanicalparametersthatcharacterizetheexcitationandthebody,atwo-dimensionalmodel,whichisnotabletoconsiderthe3Drockingonavertex,canprovideunsaferesults.Inparticular,itisfoundthattheoverturningprocessofthethree-dimensionalblockcanoccurunderexcitationswhicharelowerthanthosewhichoverturnacorrespondingtwo-dimensionalblock.

  • 标签: SEISMIC EXCITATION 3D RIGID BLOCK rectangular
  • 简介:Wesuccessfullyemployanautomaticcentroidmomenttensor(CMT)inversionsystemtoinfertheCMTsolutionsoftheFebruary12,2014MS7.3Yutian,Xinjiangearthquakeusingnear-fieldseismicwaveforms(4°<△<12°)observedbythevirtualChinaseismicnetworks,whichhavebeenrecentlysetup.Theresultsindicatethatthiseventoccurredonaruptureplane(strike243°,dip70°,andrake-18°),showingleft-lateralstrike-slipfaultingwithaminornormal-faultingcomponent.Thecentroidinthehorizontaldirectionislocatednearly13kmeastoftheepicenter(36.123°N,82.499°E),andthebest-fittingcentroiddepthisaround10km.Thetotalscalarmoment,M0,isretrievedwithanaveragevalueof3.05×1019N·m,correspondingtomomentmagnitudeMW6.92.Mostoftheenergyisreleasedwithinabout14s.Moreover,wediscussaboutthepotentialapplicationofthissysteminearthquakedisasterdecision.

  • 标签: 地震波形 矩张量 快速测定 质心 新疆 反演系统
  • 简介:DstructuralreconstructionofMohointheTangshanearthquakeareabyusinginversionofcurvedinterfaceXIAOLINGLAI(赖晓玲)XIANKANGZHANG...

  • 标签: sectional INCOMPLETE POLYNOMIAL INTERFACE 3 D
  • 简介:2006年7月4日11时56分河北省文安县(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。

  • 标签: 文安地震 震害分析
  • 简介:本文根据共和6.9级地震发生的地质构造环境及发震断层的空间几何学特征,分析了区域构造活动、变形特征及共和盆地块体的应力平衡,作者认为:龙羊峡水库蓄水荷载,破坏了原有盆地块体的应力平衡,以及水对盆地南缘隐伏断层局部地段的弱化是导致本次地震发生的主要原因。

  • 标签: 发震断层 水库地震 应力平衡 共和盆地
  • 简介:通过对我国GM4磁通门磁力仪使用的各种电源设备所产出的观测数据动态曲线的对比研究,认为电源设备对观测数据的影响不容忽视,市电结合UPS方式是最为合适的供电选择。

  • 标签: 磁通门磁力仪 供电电源 观测资料
  • 简介:本文将数字台网建立以来使用数字地震记录仪中遇到的仪器设备故障及环境对仪器设备的影响加以总结。

  • 标签: 数字地震记录仪 设备故障
  • 简介:BasedonthefirstarrivalPandSdataof4625regionalearthquakesrecordedat174stationsdispersedintheYunnanandSichuanProvinces,the3-Dvelocitystructureofcrustanduppermantleintheregionisdetermined,incorporatingwithpreviousdeepgeophysicaldata.Intheuppercrust,apositiveanomalyvelocityzoneexistsintheSichuanbasin,whereasanegativeanomalyvelocityzoneexistsinthewesternSichuanplateau.TheboundarybetweenthepositiveandnegativeanomalyzonesistheLongmenshanfaultzone.TheimagesoflowercrustanduppermantleintheLongmenshanfault,Xianshuihefault,Honghefaultandothersshowthecharacteristicoftectonicboundary,indicatingthatthefaultslikelypenetratetheMohodiscontinuity.Thenegativevelocityanomaliesatthedepthof50kmintheTengchongvolcanicareaandthePanxitectoniczoneappeartobeassociatedwiththetemperatureandcompositionvariationsintheuppermantle.TheoverallfeaturesofthecrustalandtheuppermantlestructuresintheSichuan-Yunnanregionaretheloweraveragevelocityinbothcrustanduppermostmantle,thelargecrustalthicknessvariations,andtheexistenceofhighconductivitylayerinthecrustor/anduppermantle,andhighergeothermalvalue.AllthesefeaturesarecloselyrelatedtothecollisionbetweentheIndiaandtheAsiaplates.ThecrustalvelocityintheSichuan-Yunnanrhombicblockgenerallyshowsnormalvalueorpositiveanomaly,whilethenegativeanomalyexistsintheareaalongthelargestrike-slipfaultsastheblockboundary.Itisconducivetothecrustalblockside-pressingoutalongthefaults.Inthemajorseismiczones,theseismicityisrelativetothenegativeanomalyvelocity.Moststrongearthquakesoccurredintheupper-midcrustwithpositiveanomalyornormalvelocity,wherethenegativeanomalyzonegenerallyexistsbelow.

  • 标签: REGIONAL earthquake MOHO DISCONTINUITY 3-D velocity
  • 简介:AstatisticalanalysisontheWenchuanaftershockactivitytriggeredbytidalforcesissystematicallystudiedbasedonSchusterstest,includingearthquakestriggeredbytidalforce,tidalstressandtidalcoulombfailurestress.TheresultsshowthatagroupofstrongaftershockswhichoccurredattheendofJulytoearlyAugustin2008atthenorthofWenchuanwereobviouslytriggeredbyearthtide,thesameconclusionisdrawnbySchusterssmoothtestofthetidalforce,tidalstressandtidalcoulombfailurestress.Inaddition,theWenchuanaftershockactivityisobviouslytriggeredbyfortnighttide.Inthenorth,theaftershockshappenedmorefrequentlyinthefirstandlastquartersofthemoon,andinthesouth,theaftershockshappenedmorefrequentlyinthefirstandlastquartersofthemoonandduringthefullmoon.

  • 标签: 统计分析系统 余震活动 地球潮汐 汶川 触发 库仑破裂应力
  • 简介:本文以地震对应法分析了莆田地震台DK1应力孔的前兆异常特点。

  • 标签: 地应力 前兆异常
  • 简介:2009年4月19日新疆阿图什市阿合奇县(41.1°N,78.3°E)发生了Ms5.5级地震。此次地震前,阿合奇台地倾斜资料、乌什台水管倾斜资料和二氧化碳、巴楚台地应力均出现了明显的震前异常。趋势异常表现为年变畸变;短临异常表现在矢量加速和减速。

  • 标签: 阿合奇5.5级地震 前兆异常 异常特征