摘要
The Hewanchang gas field located in the northern part of the western Sichuan Basin is a complex gas field with diversified hydrocarbon origins, various reservoirs and multiple pay zones. The authors studied the geochemical behaviors and sources of gas in this field. Based on the wide distribution of bitumen in the reservoirs in the study area, it is believed that the gases in the Ordovician and Permian are sourced from the Silurian, while the gas in the Lower Triassic Feixianguan Formation is a mixture of oil-type gas from the Permian carbonates and the coal-derived gas from the Upper Permian Wujiaping Formation.