Abstract：Using high resolution remote sensing images, we accurately extract the water body boundary of the head area of the Three Gorges reservoir. A precise discretized numerical model is constructed for the water body to simulate and calculate the gravity effect of the head area of the Three Gorges reservoir at different storage and release water levels. We finely preprocess the continuous observation data of the gPhone 101 gravity gravimeter at Zigui station in 2017 and the gPhone 113 gravity gravimeter at Maoping station in 2019 to 2021. The results show during the water storage process from 145 m to 175 m, the simulation values of gravity change on the bank at different storage levels (distance is 5 m) are 0 to 28 μGal, 0 to 47 μGal, 0 to 60 μGal, 0 to 97 μGal, 0 to 170 μGal, and 0 to 210 μGal, respectively. There is an effect of 10 to 20 μGal within 2 km from the bank at the time when the storage level is elevated by 5 m. When the water storage level increases 30 m, there is an effect of 30 to 40 μGal within 5 km from the bank. The gravity residuals mainly reflect the hydrological gravity effect information, the gravity residuals at Zigui station recorded about 40 μGal of gravity change, and the gravity residuals at Maoping station recorded about 50 μGal of gravity change. The gravity change trend and the water level change show very good consistency, verifying the accuracy of the model simulation results, and provides a reference for the stability monitoring of the head area of the Three Gorges reservoir and its banks.
LI Hui,LIU Ziwei,JIANG Ying et al. Construction and Observation of Gravity Effect Model of Water Storage and Release in the Head Area of the Three Gorges Reservoir[J]. jgg, 2024, 44(8): 867-872.
