摘要
本文介绍了兰州形变台水管倾斜仪和石英伸缩仪1987年初至1990年底观测资料的调和分析结果和各分量的年变化,分析了M_2波γ和α因子的月重复精度及其对非潮汐变化的监测能力和本区当前的构造活动特征,对异常变化与1990年10月20日甘肃景泰Ms6.2级地震之关系作了初步探讨。
The Lanzhou deformation station is located at 103°. 75E and 36°. IN. The FSQ water tube tiltmeter and SSY-Ⅲ quatz tube tiltmeters with high precision and automatic recording are installed in the station in 1986. In this paper, the tidal factors of M_2 wave and the annual variation of the inclination and strain during 1987—1990 are described,and the relation of the deformation to the structure activity of Lanzhou region and to the earthquake(λ=103°. 63E,φ=37°. IN,Ms=6.2,on Oct. 20, 1990)is discussed.Generally, the monthly repeatability errors of the tidal factors of M_2 wave are less than 0. 01. There is a trend negative anomaly in the factors of SSY-Ⅱ in 1990,the maximum variation is 11% for α_(NS) and 6% for α_(EW). During 1987—1989,the increasing variation rate of the line strain of NS direction is more than 1×10^(-6)/a and the inclination variation towards the north is 0.2s/a. Based on the results mentioned above as well as the fact that the EW walls in the epicenter toppled and fell mostly towards the north, at present the crust of Lanzhou region is pressed by the approximate SN directional force, and the generation process of Jingtai earthquake is gradually quickened. The tilt vector of FSQ are consistent with the orientation of the epifocus of Jingtai earthquake.
出处
《地壳形变与地震》
CSCD
1992年第3期55-60,共6页
Crustal Deformation and Earthquake
关键词
地震
震级
观测
潮汐
tidal factor, tilt, Jingtai (Ms= 6.2)earthquake
