摘要
本文利用Sato模型,选取2008—2009年宁夏地震台网记录的121次ML≥2.0地震的数字地震波资料,计算宁夏及邻区平均尾波Q值,并拟合了Q值对频率的依赖关系。结果表明,与国内其他地区相比,宁夏及邻区Q值较低,对频率f依赖性较高。结合研究区同期地震活动水平及地震地质构造特征,将研究区划分为四个小震密集区:吉兰泰地震区、银川地震区、卫宁同地震区、固海地震区。分别统计并拟合Q值对频率的关系式为Q(f)=(53.59±17.08)f0.9148±0.0692;Q(f)=(53.04±16.29)f0.921±0.0777;Q(f)=(42.25±15.03)f0.9532±0.0787及Q(f)=(41.65±13.46)f0.9636±0.0774。对拟合结果进行比较表明,Q值分布较好地反映了相关构造区构造活动及地震活动水平。
Based on the Sato model,adopting digital wave datas of 121 earthquake above ML2.0 from January 2008 to December 2009,which were recorded by Ningxia earthquake nets,the average Q value of seismic coda in relative regions is calculated,and the relationship between Q value and frequency is polyfited.The whole region′s result is Q(f)=(44.81±15.87)·f 0.9491±0.0805.Compared with other regions,the Q value of seismic coda in Ningxia and adjacent regions is relatively lower,but the dependence on frequency is higher.According to the regional seismic tectonic characteristics and the homochronous seismic activity,we divided the research region into four concentrated minor-earthquake areas:(a) Ji Lantai,(b) Yin Chuan,(c) Wei Ningtong,(d) Gu Hai,and the calculated Q values of the four regions relatively are:(a) Q(f)=(53.59±17.08)f 0.9148±0.0692,(b) Q(f)=(53.04±16.29)f 0.921±0.0777,(c) Q(f)=(42.25±15.03)f 0.9532±0.0787,(d) Q(f)=(41.65±13.46)f 0.9636±0.0774.Comparison of the polyfited results shows that Q value′s distribution reflects the related region′s tectonic activities and seismic activity.
出处
《地震》
CSCD
北大核心
2011年第1期118-126,共9页
Earthquake