Shale Reservoir Heterogeneity: A Case Study of Organic-Rich Longmaxi Shale in Southern Sichuan, China

Shale reservoir heterogeneity is strong, which seriously affects shale gas evaluation and reserves estimation. The Longmaxi Formation of the Luzhou block in southern Sichuan was taken as an example to characterize pore distribution over full scale using micro-computed tomography (CT), focusing on ion beam scanning electron microscopy (FIB-SEM) small-angle neutron scattering (SANS); further, explored quantitatively within different scales. results show that micropores are dominated by microfractures mainly developed along bedding direction associated with organic matter, contributing 1.24% porosity. nanopores more developed, 3.57–4.72% porosity have strong locally at microscale, but characteristics lateral homogeneity vertical macroscale. In same layer, difference only 0.1% for sheet samples 2 cm adjacent each other. Therefore, core experiments parallel needed comparison, should be position. This paper explores extent from macro micro, has important significance accurately characterizing further carrying out estimation reserves.