Microscopic pore-fracture configuration and gas-filled mechanism of shale reservoirs in the western Chongqing area, Sichuan Basin, China

FU Yonghong,JIANG Yuqiang,DONG Dazhong,HU Qinhong,LEI Zhi’an,PENG Hao,GU Yifan,MA Shaoguang,WANG Zimeng,YIN Xingping,WANG Zhanlei

Table 3 Evaluation parameters for different types of pore-fracture configuration.

Pore-fracture configuration Representative wells ϕof/% ϕwf/% ϕop/% ϕwp/% ϕof/ϕop ϕwf/ϕwp Q/% Quality Pore-hydrocarbon-generating pressurized fracture contact Z203, Z208 0.07 0.16 4.05 3.64 1.73 4.40 28.22 Good Pore-clay fracture separation Z201, Z208 0.29 1.05 3.83 7.23 7.57 14.52 34.27 Good Pore-mineral dissolution fracture separation Z201, Z203 0.35 0.69 3.65 4.13 9.59 16.71 36.47 Good Pore-compaction fracture separation Z203, Z206 0.42 1.06 3.68 7.23 11.41 14.66 43.77 Medium Structural micro-fracture contact Z205, Z207 0.96 0.85 3.54 7.25 27.12 10.34 72.39 Poor Organic matter edge fracture contact Z202, Z205 0.40 0.35 2.57 4.14 15.56 8.45 64.80 Poor