简介：

简介：

简介：Weselectedthe103ML≥2.5earthquakewaveformdatafromtheInnerMongolia-Ningxiaborderduring2009-2015,whichwasrecordedbytheInnerMongoliaDigitalSeismicNetworksandusedthesimplexmethod,Hyposatmethod,doubledifferencelocationmethod,anddeterministicmethod(PTD)forthedeterminationoffocaldepth,andcomparedtheresults.TheCAPmomenttensorinversionmethodisusedtodeterminethefocaldepthsoftheAlxaLeftBannerM5.8andM4.2earthquakes.Thefinalresultsofthefocaldepthbythedeterministicmethod(PTD)andthedoubledifferencelocationmethodfitwellwiththetectoniccharacteristicsoftheInnerMongolia-Ningxiaborderarea,butthoseofthesimplexmethodandtheHyposatmethoddonot.TheaveragedepthoftheInnerMongolia-Ningxiaborderseismictectoniczoneis13.32±8km.

简介：Dikeswarmsaregenerallyascribedtointrusionofmantle-sourcemagmaresultfromextension.BasicdikeswarmsaroundtheShanxi-Hebei-InnerMogoliabordersinthenorthernperipheralareaoftheNorthChinaCratoncanbedividedintofiveagegroupsaccordingtoisotopicdating:1800-1700Ma,800-700Ma,230Ma,140-120Ma,and50-40Ma.Geological,petrologicalandisotopegeochemicalfeaturesofthefivegroupsisinvestigatedinordertoexplorethevariationofthemantlematerialcompositionintheconcernedareawithtime.AndthevariousextensionalactivitiesreflectedbythefivegroupsofdikeswarmsarecomparedwithsomeimportanttectoniceventswithintheNorthChinaCratonaswellasaroundtheworldduringthesameperiod.

简介：AtUTC2017-11-1218:18:17,anMw7.3earthquakeoccurredattheborderbetweenIranandIraq(location34.886°N,45.941°E,depth23kmaccordingtoUSGS).WecarriedoutfocalmechanismandruptureprocessstudieswiththedatafromIRISdatacenter,using26far-fieldP-waveformsand25SH-waveformswithhighS/Nratioandrelativelyevenazimuthcoverage(epicentraldistance)inapointsourcemodeltoinvertforthefocalmechanismsolution;theresult(Figure1)wasusedtoconstructafinitefaultmodelforruptureprocessinversion(YaoandJi,1997;Wangetal.,2008),resultinginapreliminaryslipdistributionofthisearthquake(Figures2-4).Thecalculatedseismicmomentis1.1×1020N·m,Mw=7.3.Themaximumslipisabout700cm.