Three-dimensional reconstruction and modeling of microstructures and microchemistry in geological materials

Abstract

Computer-aided three-dimensional (3-D) reconstruction of minerals and rock fabrics enables quantification, spatial analysis, and state of the art communication of the complex spatial relations typically encountered in geological materials. An efficient and versatile combination of sample preparation, data acquisition, and processing methods has been established which renders the 3-D reconstruction of microstructures in geological materials applicable on a routine basis: rock samples are subject to a cycle of precision serial lapping and subsequent image acquisition by an electron probe microanalyzer. The yielded backscattered electron images and x-ray maps depict mineral phase distribution and chemical variation; backscattered electron images are stacked in a voxel array to be interpolated by binary processing. X-ray map data are interpolated by geostatistical methods, and the results are forwarded to one voxel array per chemical element of interest. Merging the voxel arrays by boolean and image algebraic methods enables the integrated analysis and visualization of mineral morphology and associated chemical variation in geological materials.