Qualitative and Quantitative Characterization of Porosity in a Low Porous and Low Permeable Organic Rich Shale by Combining Broad Ion Beam and Scanning Electron Microscopy (BIB-SEM)

This contribution focuses on the characterization of porosity in low porous shale using a broad ion beam (BIB) polishing technique combined with a conventional scanning electron microscopy (SEM). Porosity was traced in certain representative elementary areas (REA) and pores detected are segmented from mosaics of secondary electron (SE) images. Traced pores could be classified into two major pore-size classes. Relative large pores (> 0.5 μm²) were found in the organic matter and matrix. They contribute strongly to the overall porosity con-tent of the shale. Nevertheless the far majority of the pores traced have equivalent radius less than 400 nm. Including the latter pore class, the imaged porosity from both samples gives similar results in the order of < 1 %. (authors)