三峡水库蓄放水对地面重力变化的影响分析

针对目前对地面重力的影响分析多采用模拟计算,从而导致对蓄放水的影响范围和程度分析还存在不足的问题,该文利用资源三号(ZY-3)高分辨率多光谱遥感影像提取了三峡库区江河湖库水体数据,结合水位数据,通过负荷格林函数积分模型,计算出三峡水库蓄放水导致水位升降的过程中水体对地面重力变化的影响。研究发现:(1)以1a为周期,三峡库区库岸及长江近岸地面重力的变化趋势与水库的蓄放水时期对应;(2)三峡水库放水期间水位下降,水库库岸及长江近岸地面重力减小;蓄水期间水位上升,地面重力增大;(3)三峡水库蓄放水对库岸及长江近岸的地面重力影响最大可达1 000μGal以上,且距离长江中心线越近,地面重力变化越大。

Analysis of the influence of water impoundment and drainage in the Three Gorges Reservoir on the ground gravity change

Aiming at the problem that the analysis of influence of ground gravity majority carried on by simulation,which leads to the extent and degree of impact analysis of water impoundment and drainage problems still exist.This article used ZY-3 high resolution multispectral remote sensing image to extract the river lake water data library,the Three Gorges Reservoir with water level data,and through the integration of the Newton load model to calculate the green's function integral of the Three Gorges water impoundment and drainage result in water on the ground water level in the process of lifting the influence of gravity changes.It was found that:① for 1 year period,the Three Gorges Reservoir bank and the change trend of the Yangtze river shore ground gravity and water impoundment and drainage period corresponds;② during the Three Gorges Reservoir water levels fall,the reservoir bank and the Yangtze river shore ground gravity decreases;Reservoir during water level rise,the ground gravity;③ on the water storage of reservoir bank of the Three Gorges Reservoir and the ground of the Yangtze river shore gravity biggest can reach more than 1 000 μGal,and the closer to the center line of the Yangtze River,the greater the change of ground gravity.