简介：

简介：AMW6.4earthquakeoccurredinL'Aquila,centralItalyat1:32:42(UTC),April6,2009.WequicklyobtainedthemomenttensorsolutionoftheearthquakebyinvertingthePwaveformsofbroadbandrecordingsfromtheglobalseismographicnetwork(GSN)stationsusingthequicktechniqueofmomenttensorinversion,andfurtherinferredthatthenodalplaneofstrike132°,dip53°andrake-103°istheseismogenicfault.

简介：

简介：PnarrivaltimedataarecollectedfromthebulletinsofbothnationalandregionalseismologicalnetworkinChina.ThesedataaretomographicallyinvertedtomapthelateralvariationandanisotropyofPnvelocityinthenortheasternmarginalregionofQinghai-Xizangplateau.TheaveragePnvelocityinthisregionis8.09km/s,beingalittlehigherthantheaverageforwholeChina.HighervelocityisfoundintectonicallystableQaidambasin,whilelowervelocityisseeninandaroundtectonicallyactiveShanxigraben.Theregionwherethe1920HaiyuangreatearthquakeoccurredshowsaslightlylowPnvelocity.Anoticeableresultisthat,differingfromthetectonicallycompressiveTianshanregion,wherePnvelocityislow,theQilianshanregion,wheretheNeotectonicdeformationisalsoprimarilycompressive,showshighPnvelocity.IntheuppermostmantlebeneaththeOrdosplateauPnvelocityisinhomogeneous,varyingfromhighervelocityinsouthwesternparttoloweroneinnortheasternpart.ThismaybeattributedtopossiblemovementoftheOrdosblock,astherearestrongearthquakesallaroundtheblock.

简介：Mostpublishedstudiesoninelasticearthquakeresponseofnon-symmetricbuildingsarebasedonsimplifiedinelastic,highlyidealizedmodels,whilegeneralconclusionsregardingtheinelastictorsionalresponseofmultistorybuildingarestilllacking.Thispaperaimstoprovideausefulcontributioninthestudyofthetorsionalresponseofrealirregularbuildings.Tothisaim,themanuscriptreportsthecomprehensivestudyontheseismicvulnerabilityofanirregularRCbuilding:thehospitalbuildingofAvezzano(L’AquilaItaly).Forthismulti-storybuilding,whichisirregularinbothplanandelevation,theapplicationofnonlinearstaticevaluationproceduresisbynomeansstraightforward.Thestudyproposesanonlinearstaticprocedurebasedonpushoveranalysisunderthemultimodaldistributionoflateralloadsandacapacityspectrummethod.Thispushoverprocedureaccountsformassdistribution,highermodescontributionandmode-shapescorrelation.Furthermore,duetoitsnon-iterativefeature,itavoidsproblemsofnon-convergenceandmultiplesolutionsoftheconventionalcapacityspectrummethod.Appliedtoarealcasestudy,theprocedureisusedtoinvestigate,ina3Dplanirregularbuilding,thesensitivityoftorsionalinelasticresponsetolateralforcedistribution,highermodescontribution,accidentaleccentricityandcontrolledpointformonitoringthetargetdisplacement.

简介：本文讨论可信的历史地震资料和现代化仪器记录资料的统一使用问题。

简介：

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：AM_L3.8earthquakeoccurredonFebruary23,2014inRongchangCounty,whichislocatedatthesouthernedgeoftheSichuanBasinintheborderareabetweenSichuanandChongqing.ThispaperpresentsresultsoffocalmechanismsolutionofthisearthquakeusingtheCAP(cutandpaste)methodbasedonbroadbandseismogramsrecordedbyregionalseismicstations.OurresultsshowthatthemomentmagnitudeisM_W3.09andfocaldepthis3km.ThehypocenterofthisearthquakeislocatedclosetoaburiedfaultintheLuoguangshananticline.Oilprospectinganddeepdrillingdataindicatethatthisburiedfaultisathrustfault,strikingSW230°,dippingNW45°,and1.7kmdeep.Therearesomeinjectionwellswithintheanticline,andsignificantinjection-inducedearthquakeswereobservedduringtheperiodsofinjectionofwastewaterintothedeepformationsthroughthosewells.ThebestdoublecouplesolutionoftheM_L3.8earthquakeis247°,48°and104°forstrike,dipandrate,respectively,foronenodalplane(and46°,44°and74°foranothernodalplane),whichisinagreementwiththegeometryoftheburiedfault.Therefore,weconcludethattheM_L3.8Rongchangearthquakeispossiblytheresultoffaultingalongtheburiedreversefaultinducedbywaterinjectionunderthecompressivestressregimeinthearea.

简介：The2009MW7.8Fiordland(NewZealand)earthquakeisthelargesttohaveoccurredinNewZealandsincethe1931MW7.8Hawke'sBayearthquake,1000kmtothenorthwest.InthispapertwotracksofALOSPALSARinterferograms(oneascendingandonedescending)areusedtodeterminefaultgeometryandslipdistributionofthislargeearthquake.Modelingtheeventasdislocationinanelastichalf-spacesuggeststhattheearthquakeresultedfromsliponaSSW-NNEorientatedthrustfaultthatisassociatedwiththesubductionbetweenthePacificandAustralianPlates,withobliquedisplacementofupto6.3m.ThisfindingisconsistentwiththepreliminarystudiesundertakenbytheUSGSusingseismicdata.

简介：我们从省地震局提供的地震目录出发,首先对闽台地区进行预报对象的分区及确定,再选用方差分析、谐波分析、平稳时间序列三种数理统计方法进行预报,最后应用这三种预报结果进行多元线性回归运算,从而得到综合分析的年度地震趋势预报结果。本文是我们五年来制作年度地震趋势预报的总结性报告之一,力求从理论阐述到实践应用上,均能一一加以介绍,望大家多提意见。

简介：本文通过对西南地区1900年以来5级以上地震发生1个月内强余震资料的统计，得到了主震震级与余震震级、时间间隔与震中距之间的经验关系和统计规律。同时，以汶川主余震为例，进行了对比检验。统计结果表明，本文的统计结果是比较可靠的，对今后西南地区余震的预测具有一定的参考价值。

简介：宁夏地震局短信息统计及守护处理软件是基于本局原有短信息平台，利用VisualBasic作为开发工具、采用ADO作为数据库访问接口、结合结构化查询语言及VB的TIMER控件，实现了地震短信息发送、接收情况的统计、打印以及对接收到的地震短信息进行自动检索和分类处理等功能。

简介：Usingatimeseriesmethodthatcombinesboththepersistentscattererandsmallbaselineapproaches,weanalyzed9scenesEnvisatASARdataovertheL’Aquilaearthquake,andobtainedaShocke’sdisplacementfieldanditsevolutionprocesses.Theresultsshowthat:(1)EnvisatASARclearlydetectedthewholeprocessesofdisplacementfieldoftheL’Aquilaearthquake,anddistinctvariationsatdifferentstagesofthedisplacementfield.(2)Preseismiccreepdisplacement?displacementmutationwhenfaulting?constantlysloweddownaftertheearthquake.(3)Theareaofthestrongestdeformationandgroundrupturewasalow-lyingovaldepressionregiontothesoutheast.Surfacefaultingwithinazoneofabout22km914km,withanorientationof135°,occurredalongtheNW-strikingandSW-dippingPaganica-S.Demetrionormalfault.(4)Inanalyzinganareaofabout54km959km,boundedbynorth–southaxistotheepicenter,thedisplacementfieldhassignificantcharacteristicsofawatershed:westwardoftheepicentershowsupliftwithmaximumof130mminline-of-sight(LOS),andeastoftheepicenterwasaregionwith220mmofmaximumsubsidenceintheLOS,concentratingontherupturezone,themajorityofwhichformedinthecourseoffaultingandsubsequence.

简介：依据中国地震台网中心前兆数据库中的水温数据,绘制了中国大陆用于地震监测预报的泉水温度分布图以及井下50-149m和150-250m的水温分布图,统计了人工和数字化观测水温中长期趋势性上升或下降的测点,分析了数字化观测水温长期趋势性变化的原因.结果表明,泉主要分布在川滇、青藏高原东北缘、中天山、郯庐断裂带及邻区、北京西北和福建沿海等地,这些泉与断裂构造具有较好的空间相关性;其中水温大于25℃的温泉多分布在中强地震多发区;井水温度的空间分布具有北方地区水温低于南方地区、小区域内的温差不显著等特征,其主要受控于气候因素;井下150-250m与50-149m水温相比,符合随深度增加水温升高的地热规律;人工观测水温中10％为客观的长期趋势性变化;数字化观测水温中24％为长期趋势性变化,其中一部分是水温的客观反映,另一部分是水温仪零飘的反映.

简介：运用CUM-AIC方法分析了聊古-井气氡浓度观测资料,发现2006年4月9日山东莘县与河南濮阳交界的濮阳ML4.6级地震前气氡浓度有异常变化,异常持续时间达10天,计算结果中的转折点对应着异常的起止时间.CUM-AIC方法优于传统的一阶、二阶统计量分析方法.

简介：本文收集了青藏高原区7级以上以走滑为主的30个地震的地表破裂参数资料,拟合出了青藏高原区新的震级与破裂带长度统计关系式,并结合前人的统计关系式,分别通过破裂带长度估算震级,求出了估算震级与仪器震级的差值。同时将差值为正值（即估算震级偏大）的归为一类,差值为负值（估算震级偏小）的归为另一类,做了分析和对比。研究发现,差值为正值的地震所处的走滑断裂带一般位于一级块体或次级块体的边界断裂带上;差值为负值的地震所处的走滑断裂带大多位于一级块体或次级块体内部断裂带或断裂带的交汇处。基于上述分类的差异,作者对不同回归关系计算的差值数据进行了统计分析,分别给出了修正计算结果不确定性的参考值,为降低估算震级的不确定性提供了理论依据。

简介：本文汇总了湖南省农村房屋的安全性等级情况资料,从房屋的建造年代、结构形式、各年代所建房屋的危房率以及居民的住房质量、安全意识与房屋抗震性能的对比几个方面进行了房屋安全性状况统计分析。结合房屋典型损坏现象,分析了此次调查中房屋的损坏特征,总结了各种结构形式容易出现的问题。根据房屋典型损坏现象分析和安全性等级情况统计,得出了以下结论：湖南省农村生土结构和木结构房屋的安全性现状不容乐观;有关部门应制定一套适合农村的结构设计规范,并通过培训等方法解决农村房屋设计和施工问题;部分存在潜在严重地质灾害的地区和大山深处的房屋已无改造、新建的意义,最好整体搬迁。

简介：本文采用空间扫描方法,按选区和时段做震级—频度统计,计算年平均地震数。通过比较与分析,得出三点初步结论

简介：成都平原地震构造环境主要受近场中强地震和外围大地震的影响.成都平原内的第四系分布广泛,主要为河流相的砂卵石层夹粘土、粉土层.这种地层在土层地震反应计算时往往会产生一个峰值,具有显著的放大作用.本文共收集了107组土动力学参数的实验资料,统计分析了粉质粘土和粘土两种粘性土的实测土动力学参数,给出了它们在不同深度的动剪切模量比和阻尼比的统计值.然后,选取1个典型钻孔,建立了土层地震反应分析模型,分别运用本文“统计值”、“十五结果”、“规范值”、“推荐值”进行地震土层反应计算,从反应谱形状、地表峰值加速度和反应谱特征周期等方面,验证了本文“统计值”的适用性和针对性,结果表明在盆地内使用“规范值”和“推荐值”时应谨慎,不然可能会对工程的抗震设防产生不利的影响.本文的“统计值”比“规范值”和“推荐值”更适用于成都平原地区,对各类工程建设的场地地震安全性评价具有一定的借鉴和参考价值.