简介：本文就目前地震台站普遍使用的小规模CMOS电路构成的数字钟元件多、可靠性不高等缺点,提出以INTEL51系列单片机为核心构成的具有自动校对功能的数字钟,本系统硬件结构简单,系统可靠性强,并可自动根据BMP信号校时,操作简便且精度高。

简介：ＡｐｐｌｉｃａｔｉｏｎｏｆｃｅｒｔａｉｎｔｙｆａｃｔｏｒｓｏｆｅａｒｔｈｑｕａｋｅｐｒｅｃｕｒｓｏｒｙａｎｏｍａｌｙｅｖｉｄｅｎｃｅｓＣＦ（Ｅ）ＺＨＡＯ－ＢＩＺＨＥＮＧ（郑兆），ＪＵＮＺＨＡＮＧ（张军）ａｎｄＭＥＩＱＩＮＧ（庆梅）Ｓｅｉｓｍｏｌｏ...

简介：ＡｐｐｅｎｄｉｘＡ：Ｔｈｅｄｅｒｉｖａｔｉｏｎｏｆｅｑｕａｔｉｏｎ（４）ＩｎＦｏｕｒｉｅｒｄｏｍａｉｎ，ｄ２（ｘ）＝２ｘ２ｉｓｔｒａｎｓｆｏｒｍａｔｅｄｉｎｔｏｄ２（ｋｘ）＝－ｋ２ｘ（Ａ１）Ｗｈｅｎｅｑｕａｔｉｏｎ（３）ｉｓｎｕｍｅｒｉｃａｌｙｃ...

简介：Adetailthree-dimensionalPwavevelocitystructureofBeijing,TianjinandTangshanarea(BTTarea)wasdeterminedbyinvertinglocalearthquakedata.Intotal16048Pwavefirstarrivaltimesfrom16048shallowandmid-depthcrustalearthquakes,whichoccurredinandaroundtheBTTareafrom1992to1999wereused.ThefirstarrivaltimesarerecordedbyNorthernChinaUnitedTelemetrySeismicNetworkandYanqing-HuailaiDigitalSeismicNetwork.Hypocentralparametersof1132earthquakeswithmagnitudeML=1.7~6.2andthethree-dimensionalPwavevelocitystructurewereobtainedsimultaneously.TheinversionresultrevealsthecomplicatedlateralheterogeneityofPwavevelocitystructurearoundBTTarea.Thetomographicimagesobtainedarealsofoundtoexplainotherseismologicalobservationswell.

简介：ＣｅｒｔａｉｎｔｙｆａｃｔｏｒｓｏｆｅａｒｔｈｑｕａｋｅｐｒｅｃｕｒｓｏｒｙａｎｏｍａｌｙｅｖｉｄｅｎｃｅｓＣＦ（Ｅ）Ｚｈａｏ－ＢｉＺＨＥＮＧ（郑兆）（ＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕｏｆＡｎｈｕｉＰｒｏｖｉｎｃｅ，Ｈｅｆｅｉ２３００３１，Ｃｈ...

简介：The2008Wenchuanearthquake,amajorintraplateearthquakewithMw7.9,occurredontheslowlydeformingLongmenshanfault.Tobetterunderstandthecausesofthisdevastatingearthquake,weneedknowledgeoftheregionalstressfieldandtheunderlyinggeodynamicprocesses.Here,wedeterminefocalmechanismsolutions(FMSs)ofthe2008Wenchuanearthquakesequence(WES)usingbothP-wavefirst-motionpolaritydataandSH/Pamplituderatio(AR)data.AsP-wavepolaritiesaremorereliableinformation,theyaregivenpriorityoverSH/PAR,thelatterofwhichareusedonlywhentheformerhaslooseconstraintontheFMSs.Wecollectdatafromthreecategories:(1)permanentstationsdeployedbytheChinaEarthquakeAdministration(CEA);(2)theWesternSichuanPassiveSeismicArray(WSPSA)deployedbyInstituteofGeology,CEA;(3)globalstationsfromIncorporatedResearchInstitutionsforSeismology.Finally,129eventswithmagnitudeoverMs4.0inthe2008WESareidentifiedtohavewell-constrainedFMSs.Amongthem,83arewellconstrainedbyP-wavepolaritiesonlyasshownbyCaietal.(EarthqSci24(1):115–125,2011),andtherestofwhicharenewlyconstrainedbyincorporatingSH/PAR.BasedonthespatialdistributionandFMSsoftheWES,wedrawfollowingconclusions:(1)theprinciplecompressionaldirectionsofmostFMSsoftheWESaresubhorizontal,generallyinagreementwiththeconclusiongivenbyCaietal.(2011)butwithafewmodificationsthatthecompressionaldirectionsareWNW–ESEaroundWenchuanandENE–WSWaroundQingchuan,respectively.ThesubhorizontalcompressionaldirectionalongtheLongmenshanfaultfromSWtoNEseemstohavealeftlateralrotation,whichagreeswellwithregionalstressfieldinvertedbyformerresearchers(e.g.,Xuetal.,ActaSeismolSin30(5),1987;ActaGeophysSin32(6),1989;Cuietal.,SeismolGeol27(2):234–242,2005);(2)theFMSsoftheeventsnotonlyreflectedtheregionalstressstateoftheLongmenshanregion,butalsowereobviouslycontrolledbythefaultstosomeextent,whichwaspointedou

简介：事件波浪的明显的速度是为与理论方法模仿旋转地面运动的一个重要参数，但是当仅仅有单个record.This时，纸在一块多层的各向同性的橡皮基于elastodynamic理论讨论一个P-SV比率方法，有效地对估计困难在SMARTI的四地震的明显的速度穿的半space.The与这method.The结果被计算接近使用旅行时间analysis.Furthermore的一个方法，因素

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简介：Basedonwaveformdata,severalmethodstodeterminefocalmechanismsofsmallearthquakesweredevelopedsince1980.Kisslinger(1980)andJulian,Foulger(1996)proposedanapproachtodeterminesolutionbyusingamplituderatioofPandSwave.Schwartz(1995)devisedamethodtodeterminesolutionsbytheuseofpolaritydataandamplitudesofseismogramenvelopes.Amplitudesofshortperiodseismicwavespropagatinginaninhomogene-ousmediumaresensitivetothevariationinvelocityandQstructure.Nakamura,etal(1999)tookmediuminhomo-geneityintoaccountindeterminingfocalmechanismsofsmallearthquakesusingwaveformdata.Ifthelocationsofsmallearthquakesareconcentratedinasmallregion,wecanassumethattheraypathsfromtheeventstoagivenstationarealmostthesame.SoPandSwaveattenuationsareindependentofeventlocations.Inthiscaseitiscon-venienttodeterminefocalmechanismsoftheseeventsbyusingshortperiodPandSwavedataj.Focalmechanismsolutionsofsmallearthquakesin5regions,i.e.,Rongchang,Mabian-Muchuan,Ya￠an,BaoxingandMianzhu,whicharecoveredbytheChengduTelemeteredNetwork,areobtainedbyanalyzingthePpolarityandshortbodywaveamplitudedatarecordedinthenetworksince1992.AccordingtothemethodproposedbyGephartandForsyth(1984),basedonwelldeterminedfocalmechanismsolutionsin15sub-zonesofSichuanandYunnanarea,threeprincipalstresstensorss1,s2,ands3,insteadofaveragesofP,B,andTaxisofthesolutions,aredeterminedtorepresenttheregionalstressfielddistribution.

简介：AnanalyticalsolutionforscatteringofplanePwavesbyasemi-cylindricalhillwasderivedbyusingthewavefunctionexpansionmethod,andconvergenceofthesolutionandaccuracyoftruncationwereverified.Theeffectofincidentfrequencyandincidentangleonthesurfacemotionofthehillwasdiscussed,anditwasshownthatahillgreatlyamplifiesincidentplanePwaves,andmaximumhorizontaldisplacementamplitudesappearmostlyattheinclinedincidenceofwaves,whicharelocatedatthehalf-space;andmaximumverticaldisplacementamplitudesemergemostlyattheverticalincidenceofwaves,whicharesituatedatthehill.

简介：Thispaperreviewstherecentprogressinthestudiesofexperimentalrockmechanicsandtectonophysicsconcern-ingseismologyandphysicsoftheEarth'sinteriorinChina.Theprogressispresentedinthefollowingaspects:a)Alotofresultsofexperimentandnumericalsimulationenrichourknowledgeofthebrittlefracturingprocessundertheconditionwithheterogeneityinmaterialandstructure;b)Somenewresultsonfrictionalbehaviorofnon-homogeneousfaultsrevealthecomplexityoffaultingbehavior;c)Somenewresultsonthebrittle-plastictran-sitionandplasticflowareobtained;especiallytheimportantprogressisobtainedontheologicalpropertiesofrocksinthelowercrustandtheuppermantle;d)Alotofexperimentalresultsareobtainedonrockphysicsathightem-peratureandpressureandhavebeenusedinstudyofmaterialcompositionandstate.TheseresultsprovideusefulinformationforunderstandingthephysicalpropertiesanddeformationmechanismsofmaterialoftheEarth'sinte-riorandearthquakephysics.

简介：DiffractionofplanePwavesaroundanalluvialvalleyofarbitraryshapeinporoelastichalf-spaceisinvestigatedbyusinganindirectboundaryintegralequationmethod.BasedontheGreen'sfunctionsoflinesourceinporoelastichalf-space,thescatteredwavesareconstructedusingthefictitiouswavesourcesclosetotheinterfaceofthevalleyandthedensityoffictitiouswavesourcesaredeterminedbyboundaryconditions.Theprecisionofthemethodisverifiedbythesatisfactionextentofboundaryconditions,andthecomparisonbetweenthedegeneratedsolutionsandavailableresultsinsingle-phasecase.Finally,thenatureofdiffractionofplanePwavesaroundanalluvialvalleyinporoelastichalf-spaceisinvestigatedindetailthroughnumericalexamples.

简介：本文针对国家台网速报面波震级测定时间偏长和中深源地震震级速报有一定偏差的问题,采用IASPEI推荐的宽频带体波震级mB及宽频带P波矩震级MWP对2009-2013年国家台网地震速报的大震进行了对比分析.对于经过转换成MW后的mB和MWP震级来说,其结果均与我国速报地震发布的震级M有一定的偏差,一般表现为偏小.其中,对于6.0-6.9级地震,mB偏差相对较小,但离散度相对较大（整体偏差要比平均偏差大不少）;对于7.0-7.9级地震,MWP偏差相对较小;而对于8.0级以上地震,由于震级饱和等原因,mB偏差较大,但MWP偏差相对较小,一般主要表现为偏小.总体来说,MW（MWP）的稳定性要比MW（mB）更好一些（线性回归的相关系数更大,标准误差更小）.对于综合mB和MWP震级来说,由于采取分段平均的方法,结果的稳定性有了一定的提高,但较大地震仍以偏小为主,如果在综合震级MP,上加0.2,则可以得出与M震级较为接近的结果.通过MW（mB）、MW（MWP）、MP（M）、M与MW（GCMT）的对比,可以验证综合标准震级MP（M）和国家台网速报震级M具备一定的可信度,而MP（M）可作为P波快速测定的震级,所以用MP（M）作为大震速报初报震级,在某种程度上是可行的.

简介：Aftershocksofthe2011Tohoku-Okigreatearthquakehaveawiderangeoffocaldepthsandfaultplanemechanisms.Weconstrainthefocaldepthsandfocalmechanismsof69aftershockswithMw[5.4bymodelingthewaveformsofteleseismicPanditstrailingnear-surfacereflectionspPandsP.Wefindthatthe‘‘thrustevents’’arewithin10kmfromtheplateinterface.Thedipanglesofthesethrusteventsincreasewithdepthfrom*5°to*25°.The‘‘non-thrustevents’’varyfrom60kmaboveto40kmbelowtheplateinterface.Normalandstrike-slipeventswithintheoverridingplatepointtoredistributionofstressfollowingtheprimarygreatearthquake;however,duetothespatiallyvariablestresschangeintheTohoku-Okiearthquake,anunderstandingofhowthemainshockaffectedthestressesthatledtotheaftershocksrequiresaccurateknowledgeoftheaftershocklocation.

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.

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

简介：本文分析了台湾恒春海外的一次地震的记录波形的P波的主要特征。首先对其首波PN进行分析,结果表明其线性关系较好,计算出的速度值与华南地区近震走时表中所用的地壳模型中的速度值一致。其次对其PN波的续至波进行分析,发现该处的地震其射线穿过台湾岛后的地震记录波形明显与没有穿过台湾岛的不同,即没有穿过台湾岛的地震记录波形中首波震相之后明显存在有另一组震相,而穿过台湾岛后的地震记录波形则没有或不明显。该组震相最明显特征是它与首波的到时差随震中距的加大而减小,据此,作者认为它可能是一组波,即地壳内的双程反射波,表明该处有低速层存在。分析结果表明,台湾海峡南部即福建省的东山海外地区及泉州、漳州、永安地区的下方有一低速层存在。

简介：系统分析了KJ—1记录器对拾震器输出电压灵敏度的要求，并对SK拾震器与KJ—1记录器的连接方法进行了研究。研究结果表明，只需对SK拾震器和KJ—1记录器进行改造，就能实现两者的完美配接，而其性能优于DK—1地震仪和基式地震仪。

简介：一、地震基本参数表1　地震基本参数表发震时间年月日时分秒震　中　位　置微　观宏　观东经北纬东经北纬参考地名震级(ＭＳ)震源深度(Ｋｍ)震中烈度　地震类型　1975042504061781182°256°1183°256°德化雷峰3289Ⅳ主震型　　按微观震中定位,应在德化佛岭乡附近,宏观震中位于其东面10公里左右的雷峰乡附近。本次地震的震级为全省测定的平均数ＭＬ。二、地震烈度分布据调查,地震时有感人数较多的为雷峰乡一带,约占调查人数的20%左右,其它地点,约在10%以下,有的只是个别人有感。故圈定雷峰附近为震中区,烈度为Ⅳ度。地震时人们先闻到地声似闷雷呼呼响,后感觉到木板墙、床、门在摆动。本次

简介：近5年来，乌鲁木齐4号泉水中甲烷含量逐年呈趋势性降低。本文从泉点地质构造、水文地球化学环境入手，结合水文气象资料，分析并论正了甲烷逐年趋势性变化的原因。