【摘要】 孔雀河地区经历了复杂的构造变动和演化,地质条件非常复杂,对油气成藏条件特别是油气成因一直存在着争议。通过目前已发现的天然气藏的天然气组成特征分析、氮气成因分析、气体碳同位素分析等,探讨了孔雀河地区各个区带重点探井天然气成因。孔雀河地区天然气的甲烷、乙烷同位素组成具有典型的腐泥型天然气同位素组成特点,推算的天然气源岩的Ro值与寒武系和下奥陶统源岩Ro值大致相等,天然气形成温度大于190℃,综合分析认为孔雀河地区天然气主要是来自下古生界寒武系-下奥陶统原油高温裂解气。更多还原

【Abstract】 There has been a controversy about oil and gas accumulation,especially oil and gas origin in the Kongquehe area.This area has experienced complicated tectonic variation and evolution during the long geological history.Many methods have been comprehensively used to study the gas origin of the key exploration wells distributed over different zones of the Kongquehe area.These methods include toanalyse the characteristics of gas composition in all founded gas pools in this area,the genesis of nitrogen and the carbon isotope of the gas,etc.The methane-ethane isotope composition of the Kongquehe area is typically characterized by sapropelic natural gas isotope.The vitrinite reflectance(Ro) of natural gas source rocks is calculated to be equal to that of the vitrinite in the Cambrian and Lower Ordovician source rocks.The gas formation temperature is higher than 190℃.The analysis comes to a conclusion that the natural gas of the Kongquehe area is mainly from the Lower Paleozoic Cambrian-Lower Ordovician crude oil pyrolytic gas.更多还原