Re-recognition of “unconventional” in unconventional oil and gas

JIAO Fangzheng

Table 5 Statistics on gas saturation of typical shale gas and tight gas reservoirs in China and abroad[2, 30-32].

Country Gas field Basin Epoch Lithology Gas saturation/% Water saturation/% China Changning-Weiyuan Sichuan Late Ordovician-Early Silurian Siliceous/calcareous shale 60-74 20-35 Fushun-Yongchuan Sichuan Late Ordovician-Early Silurian Siliceous/calcareous shale 60-67 20-30 North Ordos Ordos Middle Permain Tight sandstone 44-50 50-56 North Ordos Ordos Late Carboniferous Tight sandstone 52-55 45-48 East Ordos Ordos Middle Permain Tight sandstone 40-50 50-60 America Barnett Fort Worth Mississippian Siliceous/calcareous shale 65-75 25-35 Haynesville Texas-Louisiana Salt Late Jurassic Siliceous/calcareous shale 65-85 15-35 Marcellus Appalachian Middle Devonian Siliceous/calcareous shale 65-88 12-35