Sandstone 3D compositional microstructure analysis with synchrotron-based multi-energy x-ray micro-CT

Abstract

Three-dimensional (3D) characterization of materials microstructure is important in understanding their physical and chemical properties. In this paper, the compositional microstructure of a sandstone sample from Yaodian area of Yan’an in Erdors Basin is analyzed using synchrotron-based multi-energy x-ray micro-CT data. The x-ray CT data of the sample are acquired at beam energies 25 KeV, 35 KeV and 45 KeV. The strip artifact in the sinogram images are corrected with a least square fitting method. The corrected sinogram image data are reconstructed with the X-tract software, and the reconstructed images under different energy spectra are calibrated. Finally, the multi-energy least square segmentation method is used to characterize the 3D microstructure of sandstone sample with the Data-Constrained Modeling (DCM) software. The results show that the sample has 71.8% of quartz and albite which is displayed as blue, calcite (22.3%) is displayed as red, pyrite (0.6%) is displayed as yellow and porosity (5.3%) is displayed as white.