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作为人造工程的三峡水库的建立，使得库区水体聚集，地球质量重新分布，将使地壳的物理结构以及局部地球重力场发生变化．针对上述问题，对库区的水准面、点绝对重力值、垂线方向和高程、高程基准面等的重力场变化以及地壳形变进行了研究．主要结果是：当蓄水水位达到峰值１７５ｍ（坝高）时，大地水准面有２．２３－１１．２ｍｍ的变化，点重力值有（０．８３－４．６）×１０－５ｍｓ－２的变化，垂线偏差的变化分别为－０．６２＂－６．５０＂（南北方向）和－６．４２＂－１．３４＂（东西方向）地壳的形变量为１．３２－６．６５ｍｍ，这些变化将引起测区的高程产生３．５５－１７．８４ｍｍ的变化．因此，原有库区及其附近的测量资料（包括水准、天文、重力等）必须审慎使用，并应建立库区形变监测网，对地壳形变、地震、滑坡、大坝变形等进行监测．
The establishment of the Three Gorges Reservoir as a man-made project will cause the water bodies in the reservoir area to gather and the redistribution of the earth’s mass will change the physical structure of the crust and the local gravitational field. In view of the above problems, the gravitational field changes and the crustal deformation of the reservoir area are studied, such as the level, absolute gravity, vertical direction and elevation, elevation datum and so on. The main results are as follows: When the water level reaches a peak of 175m (dam height), the geoid has a variation of 2.23-11.2mm, and the point gravity value is (0.83-4.6) x 10-5ms-2 The variation of vertical deviation is -0.62 “-6.50” (north-south direction) and -6.42 “-1.34” (east-west direction), respectively. The deformation of the crust is 1.32-6. 65mm, these changes will cause the elevation of the test area to produce 3.55-17.84mm change. Therefore, the measurement data (including leveling, astronomy, gravity, etc.) in the original reservoir area and its vicinity must be used with caution. A deformation monitoring network in the reservoir area should be established to monitor crustal deformation, earthquakes, landslides and dam deformation.