Distribution and characteristics of volcanic reservoirs in China

About forty productive oil/gas fields hosted in volcanic reservoirs have been found since 1957 in fourteen basins of China.They can be simply subdivided into two groups,the east and the west.Reservoir volcanic rocks of the east group are predominantly composed of Late Jurassic to Early Cretaceous rhyolite and Tertiary basalt,preferred being considered as rift type volcanics developed in the circum-Pacific tectonic regime.Those of the west are Permo-Carboniferous intermediate/basic volcanic rocks,being island-arc type ones developed in paleo-Asian Ocean tectonic regime.