摘要
The computation project and computation process for gravity correction values within the pure spherical coordinate system are expounded in this paper. The excellences of this computing scheme are as follows: 1) by using observational point P as the center of the computation region and by using spherical surface distances am=am-1+Δa·bm-1 (m=2, 3, …, M) as the radius, the computation region is plotted out as M girdles. Then, by using Δλ0 as the angle interval of radials from P point, all girdles are plotted out as integral N parts.This scheme for plotting out the computation region is extremely precise and its computation precision is very high; 2) under the condition of complex terrain and remarkable different altitudes, the computation precision can be improved by minimizing values of Δa, b and Δλ0; and 3) the gravity correction values of very large surveying area will not be confined by the 6° cingulum and the standard map sheet and can directly be computed by using altitude values with longitude and latitude.