Differences in Pore-forming Efficiency among Organic Macerals and Its Restriction against Reservoir Quality: A Case Study Based on the Marine Shale Reservoir in the Longmaxi Formation, Southern Sichuan Basin, China

Abstract Organic matter pores are of important significance in the shale formation system rich organic matters. Although a lot studies have discussed controlling factors past, it still lacks quantitative analysis on contributions macerals to pores. In this study, case study based overmature marine facies reservoir first submember Longmaxi Formation Silurian Weiyuan area was carried out. Besides, qualitative and identifications their pore development capacity were provided using scanning electron microscopy (SEM). The results showed that (1) pore-forming efficiency is one factor over matter. Sapropelinite shows highest (avg. 38.5%) while vitrinite, inertinite, exinite lower efficiency. (2) content sapropelinite 82.4%), higher Long111 Long113 layers. (3) has strong positive correlation with surface porosity. (4) porosity, total porosity present basically consistent variations along vertical direction single well. restricts which dominant type Hence, performances reservoir.