Lithological Characterization and Its Application Based on Three-Dimensional Structure-Coupled Joint Inversion of Gravity and Magnetic Data

Junjie Zhou^1,2*, Xingdong Zhang^1,2, Chunxiao Xiu^1,2

¹Key Laboratory of Geo-detection (China University of Geosciences, Beijing), Ministry of Education, Beijing, China.
²School of Geophysics and Information Technology, China University of Geosciences, Beijing, China.

DOI: 10.4236/ijg.2015.63016                

Abstract

Incorporating structural-coupling constraint, known as the cross-gradients criterion, helps to improve the focussing trend in cross-plot of multiple physical properties. Based on this feature, a post-processing technique is studied to characterize the lithological types of subsurface geological materials after joint inversion. A simple domain transform, which converts two kinds of participant physical properties into an artificial complex array, is adopted to extract anomalies manually from homogenous host rock. A synthetic example shows that structure-coupled joint inverted results tend to concentrate on the feature trends in the cross-plot, and the main geological targets are recovered well by a radius-azimuth plot. In a field data example, the lithological characterization reveals that the main rock types interpreted in the study area agree with the geological information, thus demonstrating the feasibility of this technique.

Keywords

Lithological Characterization, Structure-Coupled Joint Inversion, Density Contrast, Magnetization

Conflicts of Interest

The authors declare no conflicts of interest.

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