鄂尔多斯块体北缘中强以上地震活动特征分析

摘要

从阴山地震带6.0级以上地震周期性规律等角度,着重研究了该区域中强以上地震活动特征。阴山地震带6.0级以上强震自公元849年以来,具有百年尺度的周期性特征,1900年之后进入第五活跃期,且当前应变处于较高状态,未来几年内该地震带发生6级以上地震可能性较大。临河—乌海—巴彦浩特地区是7.0级地震的主体空区。ML5.0以上地震具有以东经110°为轴东西对跳特征,东经110°以西地区是新一轮中等以上地震活动的主体区域。1970年以来,发生的6次5.9级以上地震前,均存在ML4.0级以上地震空区或条带。2000年1月1日至2011年9月30日,阴山地震带逐渐形成两条明显的ML4.0级以上地震条带,条带交汇部位所在临河—乌海地区可能是未来发生强震的区域。%From the periodic law aspect of above 6.0 earthquakes in Yinshan seismic zone,the characteristics of medium-strong earthquakes in this area have been studied.There exists the characteristic of a century scale periodicity for above n 6.0 earthquakes in Yinshan seismic zone since AD 849.And since 1900 it has came to the fifth active period.At present,strain energy is at a high state.Therefore above 6.0 earthquakes in this area may be much possible to happen in the future years.Linhe-Wuhai-Bayanhot is the major rupture gap of above 7.0 earthquakes.Above ML5.0 earthquakes jump between eastern and western bordered with the axis of east longitude 110°,where exists a seismogenic zone and earthquake belt of new medium-strong earthquake activities.Since 1970,there have been above ML4.0 seismic gaps or belts before the six above 5.9 earthquakes.From January 1,2000 to September 30,2011,two obvious earthquake belts of ML4.0 earthquakes formed gradually.And Linhe-Wuhai the intersection part of the two belts is the future seismogenic zone.