简介：TheTanlu(Tancheng-Lujiang)faultisoneofthemajorstructuresineasternChina,whichcutsacrossdifferentblocksandcontrolsthetectonicactivity.UsingtheseismicdatafromtheChinaEarthquakeNetworksCenter,weinvestigatethespatialvariationsoftheb-valueintheDabie-Sulu(Jiangsu-Shandong)organicbeltbycalculatingtheb-valueofeachgrid(1°×1°)from1970to2010.Thestudyshowsthat:theb-valueissmallerintheTanlufaultanditsadjacentarea,whichmightsuggestthatthemajorearthquakerecurrenceperiodisrelativelylongduetothelowerfrequencyofsmallearthquakeactivity.InbothsidesofTanlufault,theb-valueishigherattheedgeofSulublockandtheeasternpartofDabieorogenicbelt.ThebvaluesarehigherinNorthChinacentralorogenicbelt,andsmallearthquakeactivitywhichoccurredalongthecentralorogenicbeltisfrequent.Additionally,combinedwithgeologicalandgeophysicalstudy,wefindthattheb-valuehasacertaincorrespondencerelationshipwiththelithologicdistribution,whichinformsusthatseismicactivityfeaturesarecloselyrelatedtotheinhomogeneousmediainthecrust.

简介：Inthispaper,basedonGansuDigitalSeismicNetworkdatasince1990,wecalculatedb-valueand⊿b-valueoftheneighborhoodareabeforethe2013Minxian-ZhangxianM_S6.6,earthquake.Theresultsshowthattheearthquakeoccurredatthemarginofthesignificantlylowerb-valueareainsoutheastofGansuandbeforetheearthquaketheneighborhoodareahadanobviouslyabnormal⊿b-value.Fromtheearthquakeandthespatialdistributionoflowb-value,theregionstillhasthepossibilityofgeneratingdangerousstrongearthquakes.