龙岗火山区地震震源参数研究  

SOURCE PARAMETERS RESEARCH OF MICROEARTHQUAKES AT LONGGANG VOLCANIC AREA

作　　者：梁国经 郑双凤 郑国栋[2] 李仲巍 刘达峰 金伟 

机构地区：[1]吉林省龙岗火山监测站,吉林抚松134528 [2]吉林省地震局,吉林长春130022

出　　处：《防灾减灾学报》2010年第4期22-29,共8页Journal of Disaster Prevention And Reduction

摘　　要：本文利用2007年5月-2010年6月间龙岗火山地震台网记录的火山区46个地震资料,采用Brune(1970)模式,通过几何扩散校正、介质衰减校正、仪器校正等将速度记录谱归算为震源位移谱,使用遗传算法计算拐角频率及零频极限,进而计算震源半径、地震矩等小震震源参数,并系统分析了各种参数之间的关系。研究中使用地震事件的震级为ML1.6～5.0,震源深度为5～10km。结果表明:地震矩范围为1011～1015N.m,震源半径为74～658m,地震应力降为0.14～13.1bar。地震矩与近震震级表现出半对数关系,拐角频率与地震矩呈现对数关系,应力降随震级变化不明显。Using the Brune model（1970）and 46 earthquakes recorded by seismic network in the Longgang volcanic area from May,2007 to Jun.,2010,we transferred the velocity record spectrum into hypocenter displacement spectrum by geometry difusion correction,dielectric attenuation correction and instrumental corection.The corner frequency and zero frequency were calculated by using genetic algorithm.Then hypocentral parameters including hypocentral radius and seismic moment were calculated and the relationship between them was analyzed systematically.All the events studied in this paper occurred at depths from 5 to 10 km with ML 1.6～5.0.The results show that the estimated seismic moments range from 10^11～10^15N·m and source radius are confined between 74 and 658 m and stress drop ranges between 0.14bar and 13.1bar.The results also show that there are semilogarithm relationship between seismic moments and local earthquake magnitude,and logarithm relationship between corner frequency and seismic moments.The stress drops didn＇t change obviously with the earthquake magnitude.

关 键 词：地震波谱 震源参数 地震台网 龙岗火山区 

分 类 号：P315.63[天文地球—地震学]