东海盆地丽水凹陷天然气与二氧化碳成因来源.

Lishui Sag is the most important hydrocarbon-bearing depression in the East China Sea Basin except the Xihu Sag. In recent years, oil and gas exploration in the Lishui Sag has been seriously affected by carbon dioxide gas and high carbon dioxide in natural gas reservoirs has reduced the commercial nature of oil and gas exploration. Therefore, it is clear that the origin and source of natural gas and carbon dioxide in the Lishui Sag are of great significance for oil and gas exploration in the East China Sea. According to this analysis, the cause of natural gas in Lishui Sag is mainly type II kerogen thermogenic oil-type gas, followed by type III kerogen-derived coal-forming gas and oil-type gas mixed source gas; oil-type gas is from Paleocene laurel group lake. The source rock is derived from the coal source rocks of the Lingfeng formation. Carbon dioxide is mainly inorganic gas, which is related to volcanic activity. The north-central and western volcanic activity areas in the east and west are the favorable directions for oil and gas exploration. [ABSTRACT FROM AUTHOR]