甘肃岷县漳县6.6级地震强震动观测记录与初步分析  

The Strong Motion Records and Preliminary Analysis for Minxian-Zhangxian M6.6 Earthquake in Gansu Province

作　　者：田秀丰[1] 李佐唐[1] 徐钦[1] 党红[1] 何新社[1] 

机构地区：[1]中国地震局兰州地震研究所,甘肃兰州730000

出　　处：《地震工程学报》2013年第3期497-502,共6页China Earthquake Engineering Journal

基　　金：兰州地球物理国家野外科学观测研究站开放基金(2013Y04)

摘　　要：2013年7月22日甘肃省定西市岷县漳县交界(东经104.2°,北纬34.5°)发生M6.6地震。甘肃强震动台网在该地区覆盖良好,获得了丰富的主震加速度记录。本文收集整理了此次地震中各强震动台站获得的加速度记录资料并进行了基本处理;经统计分析绘出了峰值加速度分布图。The Minxian--Zhangxian Ms 6.6 earthquake occurred on July 22, 2013, at the junction of Minxian and Zhangxian, Dingxi, Gansu Province （E 104. 2°, N 34. 5°）. The depth of this widespread earthquake was shallow, which caused huge casualties and property losses. In this re- gion, numerous professional strong motion observation stations recorded valuable acceleration re- cords that accurately reflect the ground vibration of the main shock in the corresponding region of Gansu province and play an important role in the evaluation of earthquake development trends. In the present study, these acceleration records were collected and preliminary processed, and the results of peak ground acceleration were statistically analyzed. We determined that 47 strong mo- tion stations obtained acceleration records, which included four types of strong motion seismo- graphs such as MR2002, Etna, GSR--18, and GSMA--2400. The Minxian strong motion station was the closest to the epicenter at a distance of 18. 0 km and peak accelerations of 160. 7 gal （EW）, 172.5 gal {NS）, and 78.4 gal {vertical）. The farthest station from the epicenter was Songshan at a distance of 297.3 km and peak accelerations of 3.3 gal fEW）, 3.1 gal （NS）, and 2.0 gal （vertical）. By calculation, we ascertained that the EW, NS, and vertical acceleration val- ues were 1.2~160.7 gal, 0.4~172.5 gal, and 0.4~78.4 gal, respectively. This earthquake de- cayed quickly, and the peak acceleration of stations 100 km from the epicenter was only approxi- mately 10 gal. For this earthquake, the Minxian station showed the largest peak acceleration. Located in the Minyang township of Minxian, this station is situated in a good observation envi- ronment with stable equipment; therefore, the records obtained by this station are reliable. Inaddition, the peak ground acceleration of each station gradually reduced with epicentral distance. However, But the effects of anisotropic media and site conditions may have resulted in unequal peak ground acceleration values f

关 键 词：岷县漳县6 6级地震 强震动记录 峰值加速度 

分 类 号：P315.914[天文地球—地震学]