菏泽5.9级地震前后水准测量与承压水变化关系的研究

PRELIMINARY STUDY ON THE RELATIONSHIP BETWEEN THE LEUETLING SURVEY BEFORE & AFTER HEZE 5. 9 EARTHQUAKE AND THE PRESSURE HEAD

利用深层承压水头观测结果,对东明——菏泽长水准测线8——9号测段的高差变化进行了回归计算和相关分析。认为菏泽市城区9号测点下沉的主要原因是受深层承压水头变化的影响。排除地下水影响因素后证实,1983年11月7日菏泽5.9级地震前后仅3mm左右的升降变化,表明9号测点对这次中强地震仅能反映微弱的形变信息量。

Based on the survey of fluctuations of deep pressure head,the variation of difference in height of long levelling points at 8-9 section along Dongming-Heze segment has been calculated regressively and correlatively. It is considered that the main cause of subsidence at No. 9 measuring point in Heze urban district is due to the variation of deep pressure head. It is proved after eliminating the effect of groundwater that there is only about 3mm fluctuation of water level before and after 1983 Heze earthquake, which showed that the No. 9 measuring point was of very weak impending anomaly before this moderate shock.