云南景谷M_S6.6地震地震动特征分析  

Ground Motion Characteristics of the Jinggu M_S6.6 Earthquake in Yunnan

作　　者：戴嘉伟 冀昆[1] 温瑞智[1] 任叶飞[1] 

机构地区：[1]中国地震局工程力学研究所中国地震局地震工程与工程振动重点实验室,黑龙江哈尔滨150080

出　　处：《地震工程学报》2015年第4期969-975,共7页China Earthquake Engineering Journal

基　　金：公益性地震行业科研专项(201508005);国家科技支撑计划课题(2014BAK03B01)

摘　　要：2014年8月3日云南省鲁甸发生MS6.5地震后,10月7日云南省内再次发生景谷MS6.6地震。对我国数字强震台网捕获的39组主震记录进行处理后,分析幅值参数、Arias强度以及持时参数的衰减特征,发现两次地震触发台站远场记录的地震动参数均显著低于预测方程,鲁甸地震的近场地震动参数略高于景谷地震;而鲁甸地震地震动参数衰减快于景谷地震,这可能与云南东部地区Q值低于西部地区的区域差异性特征相关。分析结果可以为研究该区域6.5级左右地震动衰减特征提供参考。The Jinggu MS6.6earthquake that occurred on October 7,2014 was another shallow earthquake following the Ludian MS6.5earthquake that occurred on August 3,2014 in Yunnan.During the main shock,39 recordings were obtained by the National Strong Motion Observation Network System of China.Within an area above intensityⅥ,only five stations were triggered by the earthquake.In this study,we calculated the peak ground acceleration（PGA）and peak ground velocity（PGV）from these recordings.The PGA and spectral acceleration of site053 JYP,which captured the maximumPGA（543gal）,were significantly higher than the design specifications of a local area.A field survey around this station confirmed that structures were seriously damaged during the main shock.The site and topography effects may be explained by significant differences between the PGAs of sites 053 JYZ and 053 JGX.We then compared the attenuation characteristics of the PGA,PGV,spectral acceleration,Arias intensity,and significant duration of the Jinggu and Ludian earthquakes.In a near-field area,all observed values of these earthquakes were significantly higher than predicted values but were lower than those predicted in far-field areas.Except for the significant duration,all strong motion parameters from the Ludian earthquake were slightly higher than those of the Jinggu earthquake.We also found most far-field observed values to be lower than those predicted for these two earthquakes.The difference in Q values in different regions of Yunnan may be the main reason for this phenomenon.

关 键 词：景谷地震 衰减特征 强震动记录 

分 类 号：P315.9[天文地球—地震学]