垂直形变测量与地应变

DETERMINING CRUST STRAINS FROM VERTICAL DEFORMATION MEASUREMENTS

讨论地壳垂直形变与地应变的关系。根据水准测量或地倾斜观测，定义了平均地倾斜与地倾斜率；根据应变与位移的关系，推导任一坐标方位角方向的地倾斜或地倾斜率与应变或应变率分量的关系。根据分析，初步得出结论：在１个水准点上，如果有与不同方向的８个水准点之间的高差以及距离的观测值，且这８个水准点不在同一平面内，则理论上可唯一地确定６个应变分量；在某一区域，如果有若干个不在同一平面内的水准点，由它们可求得８个以上不同方向的地倾斜，并可按最小二乘法求得该区域的６个平均地应变分量。

In this paper,the calculation of crust strain-rate tensors from vertical deformation measurements is studied.According to repeating levelling and tilt observations, the average tilt and the tilt rate are defined firstly. Then based on displacement and strain, the formula of determining crust strain-rate tensors from vertical deformation measurements is derived. The preliminary conclusion is: (1)if having 8 observations of average tilt-rate at different directions, the strain-rate tensors can be determined; (2) the average field strain-rate tensors from field repeating levelling can be computed by using the least square method.