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

<div>(a) Relationship between depth and total organic carbon (TOC) content (%), mineral content (%), helium porosity content (%), and gas content (m<sup>3</sup>/t) of Wufeng-Longmaxi shales. (b) Crossplot of quartz content vs. TOC content. Crossplot of clay mineral content vs. TOC content. The marked numbers are contents (%) of clay minerals of Wufeng-Longmaxi shales.</div>

Geofluids

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Figure 3

Figure 3: Petrographic Characterization and Maceral Controls on Porosity in Overmature Marine Shales: Examples from Ordovician-Silurian Shales in China and the U.S. 

Figure 3 | Petrographic Characterization and Maceral Controls on Porosity in Overmature Marine Shales: Examples from Ordovician-Silurian Shales in China and the U.S. 