Petrophysical properties characterization of Ordovician Utica gas shale in Quebec, Canada

With multiple techniques, the following measurements and analysis were made to characterize the Ordovician Utica shale samples: mineralogy, porosity, microstructure, and surface wettability etc. The test of mercury injection apparatus showed that the pore size of Utica shale is 15−200 nm. X-ray diffraction (XRD) mineralogy analysis and Energy-Dispersive X-ray Spectroscopy (EDS) indicated that in Utica shale non-clay minerals are dominated by calcite and quartz, while clay minerals by illite and chlorite. With the images from scanning electron microscope (SEM), the surface microstructure examination showed various types of pores exist in Utica shale, such as intragranular, intergranular, organic etc. And the pores in organic matter (kerogen) were found in nanometer size (10 to 50 nm). A three-dimensional tomography model and a geometry model of the pores space using FIB-SEM imaging tomography were reconstructed with 250 SEM images. It provides visual insights into the petrophysical properties of Utica shale. Finally, the wettability tests displayed that Utica shale has weak-water wet to intermediate wettability.