Gravity multi-interface inversion method

Abstract

The invention discloses a gravity multi-interface inversion method. The method comprises the following steps: obtaining information of an observation point, a gravity observation value, an initial model scope, underground medium information, to-be-inversed layer position information, and regularization weights of each model functional portion; performing mesh generation on an underground medium; calculating a gravity effect of each cylindrical body for the observation point after the mesh generation of an initial model, performing accumulation, and obtaining a gravity forward modeling value; according to the gravity observation value and the gravity forward modeling value, calculating a mismatch function F1(x); calculating a total variation function F2(x); calculating a model interface inversion deviation function F3(x); according to calculation results, the regularization weights lambda2 to lambda3 of each model functional portion and the mismatch function F1(x), constructing a target function: F(x)=F1(x)+ lambda2F2(x)+ lambda3F3(x); and enabling the target function to be the smallest by use of an iteration method. Through such a mode, the gravity multi-interface inversion method can have quite good inversion precision and efficiency.

Description

technical field [0001] The invention relates to the technical field of geophysical exploration, in particular to a gravity multi-interface inversion method, which is a density interface inversion method in gravity exploration, which can obtain the undulation distribution of underground multi-layer interfaces, and has high computing efficiency . Background technique [0002] The geophysical prospecting methods mainly used in geological prospecting include gravity prospecting, magnetic prospecting, electrical prospecting and seismic prospecting. Gravity exploration uses a gravimeter to observe gravity anomalies caused by differences in the density of underground materials to find out underground geological structures and lithological anomalies. Compared with seismic and other exploration methods, gravity exploration has the advantages of good lateral resolution and low cost. Gravity exploration is divided into three major links: field gravity and magnetic anomaly collection,...

AI Technical Summary

Problems solved by technology

However, in general, the above methods all have the same limitation: it is assumed that the underground material is a single interface model, so the inversion of gravity anomalies can only obtain the depth change of a single interface

However, it should be pointed out that the methods of Martins et al. (2011) and Feng Xuliang et al. (2014) only aim at the inversion of a single interface, and the inversion object is shallow matter, which cannot invert deep matter

[0007] In summary, the existing geophysical exploration methods are difficult to deal with more complex multi-interface inversion situations, and the calculation efficiency is not high

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