物探异常换算的一种高精度法——局部坐标样条函数法

本文提出一种计算物探异常导数的新方法－局部坐标样条函数法。所谓局部坐标样条函数是指平面上有一组有序点列，把相邻节点用直线两两相连，以两点之间的弘线为横坐标，与之垂直的直线为纵坐标，建立曲线方程，并使其在内节点处具有一定的连续性，则称此曲线方程为局部坐标下的样条函数。由局部样条函数计算的导数，还需要利用方向导数转换到观测平面坐标下的导数，才能适合实际应用，这种方法具有适应于大陡度异常的优点，计算精度

Local-coordinate spline function method: an accurate method for geophysical anomaly conversion

We put forward local--coordinate spline function method: a new method for computing the derivative of geophysical anomaly. This local--coordinate spline function method can be described by the following essential points:. There is an ordered point sequence in a plane.. Adjacent points are connected by line segments.. A chord between two adjacent points is taken as x axis, and its normal line as y axis.. Establish a curve equation of certain continuity at the inside points, which is then called spline function in local coordinate system.. For the practical application, the derivatives obtained from local spline function must be converted into the derivatives in observation--plane coordinate system.This method is very applicable to the case of steep anomaly, and its accuracy is one grade higher than that of B spline function method.