IMPACT ON ABSOLUTE GRAVITY OBSERVATION AT CHANGCHUN FIDUCIAL OF JINGYUETAN RESERVOIR IMPOUNDMENT
Wang Xiaobing1,2) ;Zhang Weimin1); and Zhong Min1)
1)Key Laboratory of Dynamic Geodesy,Institute of Geodesy and Geophysics,CAS,Wuhan 430077 2)Graduate School of the Chinese Academy of Sciences,Beijing 100049
Abstract:During the period from May of 2000 to September of 2008,we used the FG5112 absolute gravimeter to measure the absolute gravity at the Changchun fiducial station (JZ06)of China Crustal Movement Observation Network four times,and also collected hydrological data near the station.From the process and analysis of the gravity observations and the hydrological data,the following conclutions are drawn:1)From 2001 to 2008,the absolute gravity increases in the last three observations,and their maximum difference reaches to 20×10-8ms-2,mainly caused by the change of the Jingyuetan reservoir water storage which most impact could reach at 15.4×10-8ms-2(The average value is 6.7×10-8ms-2).2)After the effect of reservoir impoundment is removed,the average rate of gravity change at the Changchun fiducial station is 0.61×
10-8ms-2/a,which is equivalent to the rate of the crust vertical displacement as -0.18cm/a.Therefore,the impact of reservoir impourdment on absolute gravity data and relative gravity measurements at Changchun fiducial station can not be ignored.
Wang Xiaobing,,Zhang Weimin et al. IMPACT ON ABSOLUTE GRAVITY OBSERVATION AT CHANGCHUN FIDUCIAL OF JINGYUETAN RESERVOIR IMPOUNDMENT[J]. jgg, 2009, 29(5): 72-75.