等效源法在重力位场反演成像中的研究与应用

发布时间：2018-04-19 13:29

本文选题：重力异常 + 等效源法　；参考：《成都理工大学》2017年硕士论文

【摘要】：地球物理勘探的最终目的,就是要根据获得的地球物理场的信息(异常)来求取引起该异常的地下场源体的空间位置、大小、形状、物性参数等,该工作称为地球物理反演。目前的反演方法种类比较多,但是一切反演计算都存在多解性,为了克服、或者减少反演的多解性,这是地球物理工作者长期讨论、研究的课题。本论文利用等效源二维板模型进行二维重力位场反演,求出质量并进行成像,以获得有关引起该重力异常的地下场源体的分布,以及判定其空间位置、形状大小、物性参数等。二维反演中的正演模型以前多用水平圆柱体模型,而水平圆柱体对于任意截面形状的拟合远不如用二维板的拟合度高。论文首先在深入学习了有关重力勘探、反演理论、等效源方法理论及技术的基础上,然后编写了以二维板作为模型的等效源反演成像计算程序,先进行了分别以直立板、重力倾斜板、任意多边形截面等一系列的理论模拟试验及分析;在反演中,对于等效源的设计与安排分单层与多层进行研究,设计单层等效源反演成像的结果能够把水平叠加的地质体分离开来,同时可以确定地质体的产状;多层能够确定地质体的空间位置、形状大小、物性等。同时重点研究了带地形的反演成像,其效果远远好于不考虑地形的反演效果。以及验证了反演的精度,用来进一步判定场源的信息。最后将研究成果应用在某矿区重力异常的反演成像中,根据反演质量成像结果大致圈定出与铬铁矿有关的超基性岩体,为寻找铬铁矿提供了有利靶区。证明了该研究成果具有比较好的理论意义及实际应用价值。
[Abstract]:The ultimate goal of geophysical exploration is to obtain the spatial position, size, shape and physical parameters of the source body of the underground field causing the anomaly according to the information (anomaly) of the geophysical field obtained. This work is called geophysical inversion.At present, there are many kinds of inversion methods, but there are many solutions in all inversion calculations. In order to overcome or reduce the multi-solvability of inversion, this is a long-term discussion and research topic for geophysics workers.In this paper, the equivalent source two-dimensional plate model is used to inverse the two-dimensional gravity potential field, to obtain the mass and image, to obtain the distribution of the source body of the underground field causing the gravity anomaly, as well as to determine its spatial position, shape, physical parameters and so on.The forward model in two-dimensional inversion used the horizontal cylinder model, but the fitting of the horizontal cylinder for any section shape is much lower than that of the two-dimensional plate.On the basis of in-depth study of gravity exploration, inversion theory, equivalent source method theory and technology, the inversion imaging program with 2-D plate as the model is compiled, and the vertical plate is used respectively.In the inversion, the design and arrangement of equivalent source are studied in single-layer and multi-layer.The result of inversion imaging of single-layer equivalent source can separate the horizontal superimposed geological bodies and determine the occurrence of geological bodies, and the multi-layer can determine the spatial position, shape and physical properties of geological bodies.At the same time, the inversion imaging with terrain is studied, and its effect is much better than that without considering terrain.The accuracy of the inversion is verified to further determine the information of the field source.Finally, the research results are applied to the inversion imaging of gravity anomalies in a mining area. According to the inversion quality imaging results, the ultrabasic rock bodies related to chromite are roughly delineated, which provides a favorable target for finding chromite.It is proved that the research results have good theoretical significance and practical application value.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P631.1

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