Petrographic Characterization and Maceral Controls on Porosity in Overmature Marine Shales: Examples from Ordovician-Silurian Shales in China and the U.S.

Figure 14

Log differential pore volume derived from low-pressure CO₂ adsorption for Wufeng-Longmaxi shales with samples of different total organic carbon (TOC) contents. The TOC content (wt. %) of each sample is marked in the rectangle in the third panel. The micropore size distribution up to 1.2 nm was calculated with the DFT model. Pores with have different log differential pore volumes. There are three higher peaks at approximately 0.40-0.50 nm, 0.55-0.60 nm, and 0.80-0.81 nm.