基于Levenberg-Marquardt法的中国大陆地区地震烈度分布快速评估的偏差特性分析  

Analysis of the rapid assessment of seismic intensity distribution in Chinese mainland based on Levenberg-Marquard method

作　　者：任静[1] 张丹[2] 李志强 黄帅堂 谭专条 王尅丰 陈经纶 陈宇星 REN Jing;ZHANG Dan;LI Zhiqiang;HUANG Shuaitang;TAN Zhuantiao;WANG Keifeng;CHEN Jinglun;CHEN Xingyu(China Earthquake Networks Center,Beijing 100045,China;Geophysical Exploration Center,China Earthquake Administration,Zhengzhou 450000,China;Earthquake Agency of Xinjiang Uygur Autonomous Region,Urumqi 830011,China;Hainan Earthquake Agency,Haikou 570203,China)

机构地区：[1]中国地震台网中心,中国北京100045 [2]中国地震局地球物理勘探中心,中国郑州450000 [3]新疆维吾尔自治区地震局,中国乌鲁木齐830011 [4]海南省地震局,中国海口570203

出　　处：《地震地磁观测与研究》2021年第3期97-108,共12页Seismological and Geomagnetic Observation and Research

基　　金：地震应急青年基金(项目编号:CEAEDEM202026);中国地震台网中心青年基金(项目编号:QNJJ202012,QNJJ1215041104805);地震观测报告的编制(项目编号:12150411003)。

摘　　要：地震灾害发生后,可根据地震烈度衰减关系,利用地震灾害快速评估系统初步评估烈度分布范围。为评定烈度分布结果的偏差特性,利用中国西部地区488个震例和中国东部地区182个震例的等震线数据,使用Levenberg-Marquardt非线性迭代算法进行回归,计算我国大陆分区域烈度衰减关系,并对中国大陆1990—2007年23次6.0级以上地震以及2008—2019年88次5.0级以上地震进行烈度评估。结果发现,应用本研究所得烈度衰减关系进行烈度评估,不同烈度区分布面积与实际震害面积存在一定偏差,体现在:①高烈度区:实际震害面积往往比模型面积偏大;②低烈度区:实际震害面积往往比模型面积偏小。据此提出,应用该烈度衰减关系估计震害面积时,应根据烈度大小适当放大或缩写模型面积,具体缩放度如下:8度区模型面积放大约1.5—2.0倍,7度区模型面积缩小约1.5—1.6倍,6度区模型面积缩小约1.8—2.0倍。After an earthquake occurs,the earthquake disaster rapid assessment system can be used to initially assess the intensity distribution based on the attenuation relationship of the earthquake intensity.In order to study the deviation characteristics of the initial assessment,this paper uses isoseismal lines of 488 earthquakes in western China and 182 earthquakes in eastern China to calculate regional intensity attenuation relationships on the Chinese mainland using the leastsquare iterative algorithm for linear regression.Using the intensity attenuation relationships,intensity assessments were made for 23 earthquakes with magnitude 6.0 or higher from 1990 to 2007 and 88 earthquakes with magnitude 5.0 or higher from 2008 to 2019 in Chinese mainland.The results show that there are some deviations between model and actual earthquake-damaged areas for different intensities:in high-intensity areas,the actual earthquake-damaged area is often larger than the model area and in low-intensity areas,the actual earthquake-damaged area is often smaller than the model area.When estimating the earthquake-damaged area using the relationships,the area of 8 degrees should be enlarged by about 1.5-2.0,the area of 7 degrees should be reduced by about 1.5-1.6,and the area of 6 degrees should be reduced by about 1.8-2.0.

关 键 词：地震烈度 衰减关系 等震线 灾情评估 

分 类 号：P315.7[天文地球—地震学]