Abstract:

In order to study the influence of geophysical sampling and gridding method on mapping accuracy and provide field data collection with theoretical base, we compute a certain gravity anomaly field, and calculate absolute error values(AEV) and absolute error root mean square values(AERMSV) from different sampling intervals and grid interpolation methods. According to the data error, it could conclude:  1)In a single interpolation method, small spacing causes small AERMSV. 2)When sampling interval less than the minimum scale of abnormal geological body, AERMSV will ascend from radial basis function method, modified Shepard method, Kriging interpolation method, natural neighbor method, triangulation with linear interpolation, inverse distance weighted interpolation, nearest neighbor method, to minimum curvature method; when sampling interval exceeds the minimum geological body scale, AERMSV will ascend from radial basis function method, modified Shepard method, Kriging interpolation method, natural neighbor method, triangulation with linear interpolation, minimum curvature method, nearest neighbor method, inverse distance weighted interpolation. 3)Based on AERMSV, radial basis function method, kriging method and modified Shepard’s method have smaller values, and radial basis function method is best. 4)Based on AEV, radial basis function method, Kriging method and modified Shepard’s method have smaller error.

Key words: error, two-dimensional interpolation, gridding method, geophysical exploration