青海大柴旦及周边地区尾波衰减特性研究

摘要

By means of the single scatter mode（Sato）,the variation characteristics of coda Qc value of Dachaidan earthquake swarm sequence,recorded by Dachaidan Seismic Station,were analyzed in the S-wave lapse time ranging from 60 to 90 seconds;and the coda wave Q values were calculated in the frequency from 3 Hz to 18 Hz.We obtained the relationship between coda wave value and frequency,which is Qc（f）=72±21.6·f0.93±0.08.The calculation results reflect that the coda Qc value of Dachaidan earthquake aftershock sequence was in a low level.This means Dachaidan seismic zone belongs to the tectonic active area,in consistent with the geological structure features of Dachaidan area.%采用Sato单次散射模型,利用大柴旦台数字地震资料,研究了大柴旦震群序列尾波Qc值在流逝时间窗长60～90 s时间内的变化特征,计算频率从3 Hz至18 Hz,得到Qc值随频率的变化关系：Qc（f）=（72±19.9）f0.93±0.08。计算结果反映出大柴旦地震余震序列的尾波Qc值较低,说明大柴旦震源区属于构造运动较为活跃的地区,这与大柴旦地质结构特征相符。