摘要
在重力梯度各阶张量正演中,难于求取复杂地质体的解析式,转而利用已知解析解的简单规则几何形体近似剖分地质体,其会引起较大的几何拟合误差.本文首先从全张量重力梯度解析公式出发结合等参变换基于有限元分析给出了满足地下复杂地质体正演的型函数,引入体积分的误差指示器用以估计全张量重力梯度误差,提出了适用于全张量重力梯度正演的自适应计算的策略及迭代算法,数值算例证明了本文方法的正确性和有效性.
In forward modeling of gravity gradient tensors, it is difficult to obtain analylical solutions of a complex geological body. Thus a simple regular body, for which the analgtical solution is known, is uscd to divide the geological body in an approximate manner. But such a way can produce big errors in geometric fitting. In this paper, we start from the anatgtical formulas of the complete gravity gradient tensor, in combination with isoparametric transform, and give the shape function that satisfies the subsurface geological body for finite element analysis. Then an error indicator of volume integration are introduced to estimate the error of the complete grarity gradient tensor, and propose adaptive and iterative algorithms for the forward modeling. The numerical examples show that the proposed method is correct and effective.
出处
《地球物理学进展》
CSCD
北大核心
2010年第3期1015-1023,共9页
Progress in Geophysics
基金
国家高科技发展计划项目(863计划)2007AA06Z102项目资助
