Grading evaluation and prediction of fracture-cavity reservoirs in Cambrian Longwangmiao Formation of Moxi area, Sichuan Basin, SW China

WANG Bei,LIU Xiangjun,SIMA Liqiang

Table 3 Grading evaluation criterion for gas reservoirs in Longwangmiao Formation of Moxi area.

Reservoir type Reservoir grade Porosity/% Permeability/10-3 μm2 Median throat radius/μm Surface porosity/% 1 Grade I high-quality fracture-cavity reservoir >7 >5.0 >0.7 >6 2 Grade II medium fracture-pore reservoir 4-7 0.5-5.0 0.2-0.7 3-6 3 Grade III intercrystalline pore poor reservoir 2-4 0.05-0.50 0.02-0.20 3-5 4 Grade IV non-reservoir <2 <0.05 <0.02 <3