Geochemical Characteristics of Natural Gas and Its Origin in Changling Fault Depression of Songliao Basin, Northeastern China

• 责任者：Zan Ling (State Key Laboratory of Petroleum Resource and Prospecting ; China University of Petroleum ; Beijing 102249 ; China) ; Zhang Zhihuan
• 刊名：Natural Gas Geoscience
• 出版年：2010
• 卷期：21(2)
• 关键词：天然气 ; natural gas ; 油—源对比 ; oil-source rock correlation ; 松辽平原 ; Songliao Plain
• 页码：p.331-337
• 图表：8 illus., 15 refs.
• 分类号：1003
• issnNo：ISSN1672-1926
• isbnNo：CN62-1177/TE

Based on chemical and carbon isotopic compositions of natural gas from Changling fault depression, the genetic types of natural gas were discussed, in combination with standard of gas classification and empirical pattern. Based on geologic background and geochemistry of source rock, the gas source correction was also discussed, in comparison with origin of natural gas from Xujiaweizi fault depression. In natural gas from Changling fault depression, CH₄ is dominant gas, with low content of heavy alkane gas and dryness coefficient more than 0.95, suggesting high-over mature stage of thermal maturity.  Alkane gas is of thermally decomposed gas origin source from humic kerogen, but CO₂ was sourced from inorganic gas. Alkane gas was mainly sourced from Shahezi Formation humic source rock, then from Yingcheng Formation, a little contribution of gas from Huoshiling Formation or underneath would exist.