沂沭断裂带上跨断层定点水准高值变化分析

2001年8月,沂沐断裂带上的冯家坊子和相公庄定点水准测量在更换了DiNill数字水准仪后同时出现高值变化。本文计算了冯家坊子、相公庄水准2000～2002年1～7月高差中数的偶然中误差,利用t检验、f检验对不同年相同时间段的均值、方差进行了统计检验,并结合地下水位、降雨、温度、环境等因素从定量和定性两个方面分析了水准观测值与它们之间的关系;讨论了引起水准观测值出现显著变化的原因。结果表明:冯家坊子、相公庄水准出现的高值变化与更换了数字水准仪有关,而冯家坊子水准出现的高值变化还与温度、地下水位变化有关,相公庄水准SN向出现的高值变化还与周围环境干扰有关。

Analysis of High Observation Value of Fixed Cross-Fault Leveling in Yishu Fault-Zone

High values of fixed cross-fault leveling appeared simultaneously in Feng Jiafang and Xiang Gongzhuang in Yishu fault-zone when precision levelers were replaced by DiNill-type digital ones. By utilizing the observation data from Feng Jiafang and Xiang Gongzhuang leveling from Jan. to July in 2000, 2001 and 2002, Analysis shows that the observation precisions by using precise and digital levers are different. The latter's precision is lower than that of the former. With 0. 05 confidence level, t- and f-test indicate that both mean and mean-square-error of observation by using these two-type levelers in same periods of several years are obviously different. It seems that the high values appeared are mainly conccrnd in instruments change in Feng Jiafang and Xiang Gongzhuang stations, and the variation of natural circumstance such as rainfall, air temperature etc. are also possible effecting factors. High values appeared in Feng Jiafang leveling station are related to the change of air temperature and underground water level with complex-correlation coefficient of 0. 67. In Xiang Gongzhuang leveling station, interference of circumstance nearby, such as the dewatering caused by irrigation-well near the observation station, was the im portant cause of deformation of the East/South common point.