Geochemical characteristics and geological significance of natural gas in Jinshan area of the Lishu Fault Depression

Jinshan area is located in the southeast slope belt of the Lishu Fault Depression, which is an important gas exploration target. The geochemical characteristics of natural gas in Jinshan area indicate that there are two genetic types. (1) In well Jin2, non-hydrocarbon gas reservoirs with a high inorganic CO₂ content were found. The hydrocarbon gas is featured by a high dryness coefficient. Inorganic gas was mixed with oil associated organic gas. (2) Hydrocarbon gas reservoirs were discovered in the other wells. The gas is coal-type wet gas with a high CH₄ content, and is mature or over-mature.