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随着近年绝对和相对重力测量技术的发展,在大小尺度的测网中,测量精度已经可以分别达到十分之几到百分之几μm s~(-2)(1μm s~(-2)=0.1mGal)。所以重力测量技术现在能够作为探测地壳垂直运动的一种有效工具。在把几何水准测量结果转换为由重力场定义的高度时,以及在由重复测量来控制高度参考面的时间变化时,重力测量数据都是必不可少的,因为水准测量相当费时,而且在测距很大时,存在传递的不利因素,所以用重复重力测量来加强和部分地代替水准测量具有更为重要的意义,在测定地壳垂直运动中,所测得的重力随时间的变化能否成功地应用,不仅取决于重力和高度变化之间的变换因子的可靠性,而且还取决于重力测量的精度。变换因子应该在代表性测段上由同时进行的水准和重力测量来确定。现在那种建立重力基准控制点的想法正在改变,因为绝对重力仪已经可利用,而且也有可能对相对重力观测仪器做准确的标定,利用反馈系统还可观测到微量的重力差异。因此,目前的工作重点已经放在研究环境特性量的干扰效应上,例如微地震、大气压力和地下水的平面变化,以及研究一些周期性效应如地球潮汐和极性运动。
With the development of absolute and relative gravimetric techniques in recent years, the measurement accuracy can reach several tenths to several hundredths of μm respectively in the measuring network of large and small scales. 0.1 mGal). So gravity measurement technology can now be used as an effective tool to detect the vertical movement of the earth’s crust. Gravimetric data is essential when converting geometrical leveling results into heights defined by the gravitational field, as well as when the height reference surface is controlled by repeated measurements, as leveling is time-consuming and time-consuming Therefore, it is more important to use repeated gravimetry to reinforce and partly replace leveling. In the determination of the vertical movement of the crust, whether the measured gravitational force changes over time is successful or not The application depends not only on the reliability of the conversion factor between gravity and height change, but also on the accuracy of gravity measurement. Transforming factors should be determined by simultaneous leveling and gravimetric measurements on representative sections. The idea of establishing a gravity-based control point is changing now because absolute gravimeters are already available and it is possible to calibrate relative gravimetric instruments and trace amounts of gravitational differences can be observed using feedback systems. Therefore, current work has focused on the effects of disturbances on the amount of environmental characteristics studied, such as microseismic, atmospheric pressure and groundwater level changes, and the study of some cyclical effects such as Earth tides and polar movements.