Applications of scanning electron microscopy in earth sciences

Abstract

This paper expounds upon the basic principle of scanning electron microscopy (SEM), the main features of image types, and different signals, and the applications and prospects in earth sciences research are reviewed. High-resolution field emission SEM allows observation and investigation of a very fine micro area in situ. Using low-vacuum mode SEM, geological insulating samples can be analyzed directly without coating, demonstrating the wide application prospect. Combined with backscatter detector (BSE), energy dispersal X-ray spectroscopy (EDS), cathodoluminescence spectrometry (CL), and electron back-scattering diffraction (EBSD), SEM can yield multiple types of information about geological samples at the same time, such as superficial microstructure, CL analysis, BSE image, component analysis, and crystal structure features. In this paper, we use examples to discuss the geological application of SEM. We stress that we should not only focus on the CL image analysis, but strengthen CL spectrum analyses of minerals. These results will effectively reveal the mineral crystal lattice defects and trace element composition and can help to reconstruct mineral growth conditions precisely.