简介:Spatialandtemporalvariationof gravity fieldinthecapitalregionChang-CaiHUA;(华昌才)YongGUO;(果勇)Duan-FaLIU;(刘瑞法)GangXIAO;(肖钢),J.T....
简介:Comprehensivestatisticalanalysiswasperformedonthebasicfeaturesoffocalmechanismsof619ML≥2.0earthquakeswhichoccurredinthecapitalcircleareafromJanuary2002toJune2010.Bydividingthecapitalareaintothreestudyingregionsbasedonregionaltectoniccharacteristics,clusteranalysiswasconductedonthefocalmechanismsofallsubregionsusingthelongestdistancemethodinthestatisticalclusteranalysistostudythecharacteristicsoftectonicstresstensors.TheresultshowsthatdominantP-axisazimuthdistributionisNNE-NEEandthatofT-axisisNNW-NWW,mostofthefocalareasarecontrolledbyahorizontalstressfieldandruptureismainlyofhorizontalstrike-slip.ThemaximumprincipalcompressionstressorientationisNE75°inthewest,NE62°inthemiddle,andnearEWintheeastofthecapitalarea.Theregionaltectonicstressfieldischaracterizedbyhorizontalcompression.
简介:AdenseseismicnetworkwasinstalledinthecapitalregionofChinainrecentyears,whichmakesitpossibletoresolvethefocalmechanismsofsmallearthquakes.Wegatheredlargeearthquakefocalmechanismsfromthelastfiftyyearsandmoderateorsmallearthquakefocalmechanismsfrombetween2002and2004,andcalculatedthepresenttectonicstressfieldofthecapitalregionbythegridsearchmethod,whichweighsdifferentsizedearthquakesandcanimprovetheaccuracyofthestressfieldinversion.Theanalysisofinversionresultsofdifferentsub-regionsshowsthattheazinuthofthemaximumprincipalcompressivestressaxisisNE43°-86°intheBeijing-Zhangjiakou-Datongarea,NE38°-86°intheTangshanarea,andNE79°-81°intheXingtaiarea.Inversionresultsofthispaperaresimilartopreviousresults,whichprovesthecorrectnessoftheapproach.Asrevealedbytheresults,thestressfieldofthecapitalregionischaracterizedbyoverallconsistencyandsub-regionaldifferences.Thisstudyprovidesreferenceforearthquakemechanismexplanationandgeodynamicsresearch.
简介:Inthispaper,wemadeasystematicstudyonmorethan40yearsofobservationaldataoftentemporaryfault-crossingmeasurementsitesinthecapitalcircleregionofChina.Wecalculatedhorizontalandvertica1componentsoffaultslip,andhorizontalextensionorcompressioncomponents.Consideringthetectoniccharacteristicsofthecapitalcircleregionandregionalseismicity,weanalyzedthepresentfaultactivityofthecapitalcircleregionandtherelationshipwithearthquakes.Theresultsshowthecomplexityoffaultactivityintheregion:thelevelofactivityofallfaultsislow,mostfaultsareleft-lateralstrike-slipfaults;thereislessverticalactivitythanhorizontalactivityandcrustalmovementiscontrolledbyhorizontalmovement;faultactivityandearthquakeactivityhaveacertainrelationship,regionalfaultactivityincreasesbeforeanearthquake,andfaultactivityhascertainabnormalfeaturesbeforestrongearthquakes.