2.5D地质体重磁异常无解析奇点正演计算研究

本文明确指出现有文献中有关2.5D重磁异常正演模型在上半无源空间存在某些点的场值无法计算的解析"奇点"问题,长方体ΔT场及其梯度场正演计算理论表达式在上半无源空间存在场值无法计算的解析"奇点"问题仅是2.5D体的一种特例情况。通过详尽的理论推导,建立了2.5D体重磁异常在上半无源空间无解析"奇点"正演计算模型,并在此基础上导出了新的长方体ΔT场在上半无源空间无解析奇点理论表达式。上述建立的模型或表达式是普遍适用的,同现有模型或表达式相比,具有形式统一、正演计算快速的优点,一定程度上满足了正反演中快速计算的需求。对比计算表明,所建立的2.5D体重磁异常无解析"奇点"正演计算模型和新导出的ΔT场无解析"奇点"理论表达式是正确的。

Analytic singularity-free forward computation of gravity and magnetic anomaly for 2.5-D geologic body

The paper clearly pointed out that it is only the special case in 2.5-D body that there exist the issues of analytic singularity resulting in computation of field value cannot be carried out at some points of semi passive space in forward models of 2.5-D gravity and magnetic anomaly and in forward theoretical computational expression of cuboid ΔT and gradient fields that is showed in available literatures. The analytic singularity-free forward computational model of 2.5-D gravity and magnetic anomaly on semi passive space was created by detailed theoretical derivation and new analytic singularity-free theoretical expression on semi passive space of cuboid ΔT field was deduced in that basis. Above created model or expression is universally applicable and characterized by uniform form and rapid forward computation in comparison with available model or expression,which meets the need of forward and inverse rapid computation to a certain degree. The correlative computation showed that new-created analytic singularity-free forward computational model of 2.5-D gravity and magnetic anomaly on semi passive space and new deduced analytic singularity-free theoretical expression of cuboid ΔT field are correct.