基于地震预警参数阈值评估内蒙古地区地震潜在破坏区

Evaluation of Seismic Potential Damage Area in Inner Mongolia Based on Threshold Value of Earthquake Warning Parameters

摘要:

利用内蒙古地区测震台网记录到的地震波形数据，基于地震预警参数阈值（特征周期τ_c和位移幅值P_d）开展评估内蒙古地区中强地震潜在破坏区范围的研究。按照一定的筛选条件进行筛选后，拟合出适合内蒙古地区的τ_c与震级M_L、P_d与τ_c和震源距R的统计关系式；根据现有地震事件的最大震级，得到仪器烈度为Ⅳ度、震级M_L=5.0时对应的参数阈值为P_d=0.1075cm和τ_c=0.686s。最后对近年来内蒙古境内2次中强地震开展线下模拟，结果表明该方法需要台网具有一定密度，如能均匀分布，效果更好，否则会出现结果仅由经验关系式决定、而实际观测值没有发挥作用的问题。

Abstract:

Based on the threshold value of earthquake warning parameters(characteristic period τ_c and displacement amplitude P_d),we use the seismic waveform data recorded by Inner Mongolia seismic network to study the estimation method of potential damage area of moderate strong earthquake in Inner Mongolia in this paper. According to certain screening conditions,the statistical relations between τ_c and M_L,P_d and τ_c and epicentral distance R are fitted out. Then according to the maximum magnitude corresponding to the existing earthquake events,when the instrument intensity is set as IV and M_L=5.0,the corresponding parameter thresholds are P_d=0.1075cm and τ_c=0.686s. Finally,two moderate strong earthquakes in Inner Mongolia in recent years are simulated. The results show that the relatively higher network density is required in application of this method. If the network can be evenly distributed,the effect will be better. Otherwise,the result is only determined by the empirical relationship,but the actual observations do not come into play.