摘要
利用数字化地震台网资料研究构造环境应力场,可以把原来仅限于使用地震震级mb≥3.8的地震资料扩大到MW=1.8,这样大大增加了对于目前地震活动性较弱地区地震资料的使用,加强了对于一些重点地区潜在危险性的研究。利用中国与欧共体合作在北京西北怀来建立的数字化台网资料,采用SEISAN地震分析软件,得到了北京地区42次地震的峰值加速度值,峰值速度值,峰值位移值,地震矩M0,矩震级MW。提出了适用于京西北地区的地震波衰减模式,在陈培善推导的计算公式基础上计算了京西北地区的环境应力值τ0。据此,结合北京地区历史地震的分布推测了这些地区的地震危险性。结果表明,近期发生大地震的可能性不大。
he digital seiemic data are used to study the tectonic ambient shear stress field.It can enlarge the range of usable data,that means the magnitude is decreased from mb=38 to MW=18. It is very useful to research the potential seismic hazard of important region where earthquake activity is low at present.Using the SEISAN,an earthquake analysis software,the values of peak acceleration and velocity and displacement,moment and moment magnitude MW of 42 earthquakes in Beijing area have been obtained by analyzing the data from the SinoEuropean Cooperative Huailai Digital Seismograph Network,in northwestern Beijing. The model of seismic wave attenuation which is suitable for Beijing area is presented.Using the formula for calculating tectonic ambient shear stress value,which are put forward by Chen Peishan,the tectonic ambient shear stress value τ0 of 42 earthquakes occurred in Beijing region have been calculated.Combinng the τ0 values with the distribution of history earthquakes occurred in Beijing area,the seismic hazard regions were estimated.The results suggest that it is nearly impossible for large earthquakes to occur in the near future.
出处
《地震地磁观测与研究》
1998年第4期8-16,共9页
Seismological and Geomagnetic Observation and Research
基金
中国地震局"九五"重点攻关项目
关键词
北京
地震危险性
构造环境
剪应力场
地震数据
ambient shear stress filed Beijing area,seismic hazard, digital seismic data,digital seismograph network