简介：InordertoexploretheabnormalvariationsbeforeandaftertheWen'anM5.1earthquakeonJuly4,2006,thegravitydataobservedbytheWenbaGravityObservationNetworkbeforeandaftertheearthquakewasanalyzed.Therelationshipsbetweengravitychangeandverticaldisplacementandshallowgroundwaterlevelwerediscussed,andelevationcorrectionofthegravitywaspreliminarilyperformed.TheresultsshowthattherewereabnormalgravitychangesbeforetheM5.1earthquake,whichappearedasgravityrisinginthewholeobservationnetwork,especiallyinthesouthpart.AhighgradientofgravityvariationappearedaroundtheepicenterbeforetheM5.1earthquake,especiallyduringtheshortperiodbetweenOctober2005toApril2006.TheboundaryofthepositiveandnegativegravityvariationsgraduallydeflectedandbegantorecoverfromOctober2007.

简介：本文收集了733个四川地区的实测钻孔数据,从中筛选出深度大于30m的268个钻孔剖面资料.分别获得了10m、15m、20m、25m和28m不同深度处的平均剪切波速（Vs）（d）与（Vs）（30）的对数线性相关关系.同时还与Boore（2004）的结果做了对比分析,比较了采用常数外推法和对数线性外推法得到的不同深度处剪切波速的残差分布.结果表明,不同深度处剪切波速（Vs）（d）与（Vs）（30）的对数相关关系可能具有一定的区域性特征,本文得到的对数关系更适合四川地区.对数线性外推法与常数外推法相比,前者的系统偏差更小;随着深度的增加,两种方法的外推误差均逐渐减小,但常数外推法普遍低估了（Vs）（30）值;当深度较浅时,低估的情况更为明显.本文的研究结果为利用大量的不足30m的钻孔资料估计（Vs）（30）值提供了参考.

简介：Basedondatacollectedfromatemporalseismicnetwork,andinadditiontothedatafromsomenearbypermanentstations,weinvestigatethevelocitystructureandseismicityintheRongchanggasfield,wheresignificantinjection-inducedseismicityhasbeenidentified.First,weusereceiverfunctionsfromdistantearthquakestoinvertdetailed1-Dvelocitystructuresbeneathtypicalstations.Then,weusethedouble-differencehypocenterlocationmethodtore-locateearthquakesofthe2010ML5.1earthquakesequencethatoccurredintheregion.There-locatedhypocentersshowthatthe2010ML5.1earthquakesequencewasdistributedinasmallareasurroundingmajorinjectionwellsandclusteredmostlyalongpre-existingfaults.Majorearthquakesshowafocaldepthlessthan5kmwithadominantdepthof～2km,adepthofmajorreservoirsandinjectionwells.Wethusconcludethatthe2010ML5.1earthquakesequencemighthavebeeninducedbythedeepwellinjectionofunwantedwateratadepth～3kmintheRongchanggasfield.

简介：Completerecordsofmorethan3,000earthquakeeventsintheShanxi,WenzhoureservoirearthquakesequencewererecordedfromAugusttoNovember,2014bythehigh-density,high-resolutionmonitoringstationsoftheZhejiangRegionalDigitalSeismicNetworkandthereservoirearthquakemonitoringnetwork,withamaximummagnitudeofM4.2.Basedon3-Depicenterlocation,focalmechanismsolutions,andincombinationwiththegeologicalandtectoniccharacteristicsofthereservoirarea,theearthquakesequenceisdiscussedinthispaper.ThelinearfittingoftheHypoSATlocationresultsshowthatthemainshockoccurredintheNWtrendingfaultandtheearthquakesequenceisconcentratedinbandsalongtheactivefaults,withastrikeof305°,dippingSWwithdipangleof85°.ByusingP-wavefirstmotionsymbols,weobtainedtheaveragefocalmechanismofM≥3.5earthquakes,withastrike308°anddip84°fornodalplaneII.Thefieldgeologicalsurveyandresearchshowthatthestrike,dipandrakeofnodalplaneIIareroughlyconsistentwiththeoccurrenceoftheShuangxi-Jiaoxifault.ThecomprehensiveanalysisrevealsthattheNW-trendingShuangxi-Jiaoxifaultistheseismogenicstructureoftheearthquakes.

简介：ＰｒｏｃｅｓｓｏｆｓｏｕｒｃｅｄｙｎａｍｉｃｓｏｆｔｈｅＪｉｎｇｔａｉｅａｒｔｈｑｕａｋｅ（Ｍ＝６．２）Ｘｕｅ－ＢｉｎＤＵ（杜学彬）；Ｚｈｉ－ＤｅＹＡＮ（闫志德）ａｎｄＭｉｎｇ－ＷｕＺＯＵ（邹明武）（ＥａｒｔｈｑｕａｋｅＲｅｓｅａｒｃｈＩｎｓｔｉｔｕ...

简介：Therehavebeen12possiblelocationsoftheearthquakesoccurringintheSouthYellowSeasince1505.Inthispaper,thelocationoftheearthquakethatoccurredin1505hasbeendeterminedbythecollectionofmorehistoricaldataoftheinfluencedfield,referringtheisoseismaldataofearthquakeswiththeepicentralintensityⅨandcombininggeophysicalfielddatawithtectoniccondition,duetoitsgreatinfluenceonseismicsafetyassessmentofsomesignificantengineering.

简介：通过云南M≥7．6级地震震亡分布的统计，研究大地震的伤亡分布规律，寻找影响伤亡的主要原因。结果表明，震亡人数主要分布在Ⅷ度以上烈度区，这一区域的震亡人数占震亡总数的94％以上，其中极震区占到70％以上。调查分析认为：在震级相近的情况下，震区地质构造、地形地貌是影响地震烈度的因素；房屋、人口密度、发震时间是震亡人数的重要影响因素；在未来的大地震中，人口密度大的断裂带及其附近是应急救援和医疗救护的重点区域，在断裂带及其附近盆地内的震亡人数比非盆地震亡人数多，要投入更多的救援和医疗救护力量。

简介：Thispaperisthesecondinatwo-partseriesthatdiscussestheprincipalaxesofM-DOFstructuressubjectedtostaticanddynamicloads.Theprimarypurposeofthisseriesistounderstandthemagnitudeofthedynamicresponseofstructurestoenablebetterdesignofstructuresandresponsemodificationdevices/systems.Underidealizeddesignconditions,thestructuralresponsesareobtainedbyusingsingledirectioninputgroundmotionsinthedirectionoftheintendedresponsemodificationdevices/systems,andbyassumingthattheresponsesofthestructureisdecoupleableinthreemutuallyperpendiculardirections.Thisstandardpracticehasbeenappliedtobothnewandretrofittedstructuresusingvariousseismicprotectivesystems.Verylimitedinformationisavailableontheeffectsofneglectingtheimpactofdirectionalcouplings(crosseffectsofwhichtorsionisacomponent)ofthedynamicresponseofstructures.Inordertoquantifysucheffects,itisnecessarytoexaminetheprincipalaxesofstructuresunderbothstaticanddynamicloading.Inthistwo-partseries,thefirstpaperisconcernedwithstaticloading,whichprovidesdefinitionsandfundamentalformulations,withtheconclusionthatcrosseffectsofastaticallyloadedM-DOFstructureresultingfromthelackofprincipalaxesareofinsignificantmagnitude.However,underdynamicorearthquakeloading,arelativelysmallamountofenergytransferredacrossperpendiculardirectionsisaccumulated,whichmayresultinsignificantenlargementofthestructuralresponse.ThispaperdealswithaformulationtodefinetheprincipalaxesofM-DOFstructuresunderdynamicloadinganddevelopsquantitativemeasurestoidentifycrosseffectsresultingfromthenon-existenceofprincipalaxes.

简介：Ｔｈｅ　ａｎａｌｙｓｉｓ　ｏｆ　ｄｉｓｋ　ｃｏｒｅ　ｆｒｏｍ　ｔｈｅ　Ｍａｏｐｉｎｇ　８００　ｍ　ｂｏｒｅ　ｈｏｌｅ（阮小平）（李方全）ＴｈｅａｎａｌｙｓｉｓｏｆｄｉｓｋｃｏｒｅｆｒｏｍｔｈｅＭａｏｐｉｎｇ８００ｍｂｏｒｅｈｏｌｅ￥Ｘｉａｏ－Ｐｉｎｇ...

简介：AnM8.1earthquakethatoccurredwestoftheKunlunMountainsPasshascausedmorethan20collapsebodiesorzones,whicharemainlydistributednearthesurfaceseismicrupturezone,westofHohSaiLake.Thecollapsesareoffourtypes,bedrock,soilmassandicemasscollapsesandavalanches.Thespatialdistributionandthecharacteristicsofdevelopmentofthecollapsesareanalyzedinthepaper.Comparisedwiththosecausedbyotherearthquakes,thecollapsesaresmallerinscale.Inadditiontothelithologicalcharacteristicsofthecrustalmedia,topographic,geomorphicandclimaticfactors,weakerseismicgroundmotionisanimportantcauseforformationofthesmaller-scalecollapses.Thelongsurfacerupturezoneandweakergroundmotionareimportantfeaturesoftheseismicrupture,whichmayberelatedtothestructureofthepreexistingfault.

简介：1861M6。0地震发生在Pulandian的东方是有M6的另一强烈地震。0除1975HaichengMT以外。在Liaodong半岛的3地震。通过重复调查，1861地震的震中在Gupao被定位，Pulandian的村庄东方。基于损坏调查和现代仪器的地震数据，这项活动和Jinzhou差错，Pulandian海湾差错和趋势NW的地震风险的精确地点的分析Pulandian差错被分析。并且由比较在Pulandian和Haicheng之间的深seismogenic环境，，它被发现那neogenic活跃差错，趋势NW差错，与Jinzhou差错结合了，有更高地震的风险。趋势NW差错是1861M6的seismogenic结构。0地震。并且作为在Liaodong半岛的一个主要差错，Jinzhou差错控制了这个区域的seismicity。Pulandian海湾差错是相对不活跃的，与弱seismicity，并且对地震无关。

简介：ＡｓｏｕｒｃｅｅｘｔｅｎｔａｎａｌｙｓｉｓｏｆｔｈｅＬａｎｃａｎｇｅａｒｔｈｑｕａｋｅ（Ｍｓ＝７．６）ｏｆ１９８８ＳＩ－ＨＵＡＺＨＥＮＧ（郑斯华）ＪＩＡＮＹＡＮＧ（杨健）ＣｅｎｔｅｒｆｏｒＡｎａｌｙｓｉｓａｎｄｐｒｅｄｉｃｔｉｏｎ，ＣｈｉｎａＳｅｉｓ...

简介：

简介：DetailedexaminationofhistoricaldataofearthquakesandfieldinvestigationsofloesslandslidecausedbytheearthquakeandtracingofactivefaultsinLanzhouareaindicatethattheYijitanputown,oneofsixtownsofJinchengcity,wasdevastatedbythe1125Lanzhouearthquake.ThecitlyisnowlocatedintheVinylonFactorysouthofHekou(RiverMouth)intheXigudistictofLanzhoucity.WedelerminedthatthesixoldtownsmentionedinhistoricalrecordslieinanareastretchingfromthesouthofXigudistricttoHekouinLanzhou.Thisisconsistentwiththedistibutionofloesslandslidescausedbytheearthquake,theextensionofHoloceneactivefaults,andthedistributionoftracesoftheseismicrupturezone.Acomprehensiveanalysisshowsthattheseismogenicstructureforthe1125LanzhouM7.0earthquakeshouldbetheXianshuigoufaultsegmentatthewesternterminationofthenorth-borderactivefaultzoneoftheMaxianshanMountainswhicharelocatedinsouthofLanzhoucitywiththedistanceofonly4km.

简介：Ｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｆａｕｌｔｓａｎｄｇｅｎｅｒａｔｉｏｎｏｆｉｎｌａｎｄｓｈａｌｌｏｗｅａｒｔｈｑｕａｋｅｓ：ｅｎｌｉｇｈｔｅｎ－ｍｅｎｔｏｆｔｈｅＭ＝７．２ｓｏｕｔｈｅｒｎＨｙｏｇｏｐｒｅｆｅｃ－ｔｕｒｅｅａｒｔｈｑｕａｋｅＴＯ...

简介：Amoredetailedanddeep-goinganalysisoftectonicconditionsforthe1989BohaiSeaM7.4earthquakeareahasbeenmadebasedonthedataofoilgeologicalexplorationandresultsofseismologicalresearches.TheobtainedresultfillsthegapinseismotectoulcresearchofLargeBohaiSeaearthquakeareaofNorthChina.TheearthquakeareaislocatedintheeasternpartofCenozoicriftedbasinoftheBohaiGulf,alongtheintersectionzonebetweentheNNE-trendingYingkou-WeifangfaultzoneandtheNW-trendingBeijing-Penglaifaultzone.IntheearlyTertiaryfault-depressionstage,threesetsoffaults,theNNE-,NW-,andW-E-trendingfaults,weredevelopedintheuppercrustinthearea.Theyarelistricandplanarintheform,ofnormalfaultcharacterandmostlythemajorfaultsinfaulteddepressions.Inthefault-depressionstagesincelateTertiary,thepreexistingfaultshaveundergonemovementtodifferentextent.Meanwhile,anewNE-trendingHuanghekou(YellowRiverMouth)-Miaoxibeifaultzonewasdeveloped.ThefocalfaultingoftheM7.4earthquake,strikingtoN45°EanddippingtoSE,isnearlyvertical,withdextralstrike-slipnature,andburieddowntodepthof15～34km.TheseismogenicfaultforthelargeearthquakeisnottheYingweifault,butthenewlygeneratedHuanghekou-Miaoxibeifault.

简介：At19:33p.monSeptember27,2003,anearthquakewithM7.9occurredintheRussiaMongolia-ChinaboundaryRegion.ItwasstronglyfeltintheAltayregionofXinjiang.Thelossescausedbytheearthquakewas76millionyuan(RMB).Someinformationabouttheearthquakewasoutlined,includingbasicparameters,focalmechanism,evaluationofearthquakedisasterlossesandsoon.Thesatelliteremotesensinginformationworkedinitialanalysisfordeformationofgroundandfailurephenomenon.

简介：

简介：Usingthe78focalmechanismsolutionsoftheforeshocks,mainshockandaftershocksoftheearthquakesequencefortheYao'anearthquake,thecharacteristicsofthefocalfaultsandstressfieldfortheearthquakesequenceareanalyzed.TheresultsshowthatthemainruptureplaneoftheYao'anearthquakesequenceisatectonicfaultwithN50°Wstrikeandsteepdipandallthemainshock,theforeshocksandthevastmajorityofaftershocksoccurredonthemainruptureplane.AtectonicfracturewithNNE-NEstrikealsoparticipatedindevelopmentprocessofthesequencedominatedbyprincipalcompressionalstresswithnearlyhorizontalorientationSSEisconsistentwiththeregionaltectonicstressfield.Inthesequencedevelopment,thestressfieldinthefocalregionwascomplexwithmultiaximuthsandmulti-actionmodelsandthefocalruptureshowedcomplexfeatureswithmulti-directionsandmulti-patterns.

简介：AnearthquakewithM7.1occurredinYushu,QinghaiProvince,China,at07:49a.m.onApril14,2010,accordingtotheChineseSeismicStationNetwork.Thesequenceisafore-mainafter-shocktypesequence.AforeshockwithM4.7occurred2hoursand11minutesbeforethemainshock.Therewere12foreshocksand2385aftershocksuntilJune31,2010.Inwhich,thereare21aftershocksbetweenM3.0andM3.