简介：Thisstudyrevealspreliminarilytheearthquakebehaviorofvariablerupture-scaleonactivefaultsoftheChinesemainland,thatisthatonanindividualfaultportionearthquake￠srupture-scalevariescycletocycle,andhenceearthquake￠sstrengthchangeswithtime.Thetendencyofthisvariationhasnonecessity.Ondefiningrelativesizeofrupturescales,astatisticalresultshowsthatitisofthelowestprobabilitythatruptureswiththesamescaleoccurintwosuccessivecycles.Whiletherupture￠sscaleintheprecedingcycleis2small2,theprobabilityofthefollow-ingrupture￠sscalebeing2large2isasmanyas0.48.Whiletherupture￠sscaleintheprecedingcycleis2middle2,theprobabilityofthesucceedingrupturebeing2small2or2large2scaleis0.69or0.25.Whiletherupture￠sscaleintheprecedingcycleis2large2,theprobabilitymustbezeroforthefollowingrupturewith2large2scale,andis0.36or0.64forthefollowingrupturewith2small2or2middle2scale.Theauthorintroducesandimprovesthecascade-rupturingmodel,andusesittodescribethevariabilityandcomplexityofrupturescaleonindividualfaultportions.Basicfeaturesofsomeactivestrike-slipfaultsonwhichcascaderuptureshaveoccurredaresummarized.Basingonthesefeaturestheauthorproposesprinciplesofcascade-rupturesegmentationforthistypeoffaults.Asanex-ampletoapplication,theauthorsegmentsoneportionoftheAnninghefaultzone,westernSichuan,foritsfuturecascaderupture,andfurtherassessestheprobablestrengthanditscorrespondingprobabilityofthecomingearth-quake.