塔里木盆地北部天然气成因类型特征

The Characteristics and Types of the Natural Gas Origin in the Northern Tarim Basin

塔里木盆地北部的天然气按成因类型主要可划分为腐泥型、腐殖型和腐泥一腐殖混合型气三种。其地球化学特征表现在烃类的组成、C_6—C_7的轻烃组成及同位素组成等方面有着明显的不同。主体为高成熟的腐泥型气,与海相原油密切共生;正常腐殖气与陆相原油密切相关;混合型气与不同母质来源气的混合程度有关。

The natural gas in the northern Tarim Basin can be genetically classified into three types.These are the sapropelitic- gas,the humus gas and the sapropelitic-humus hybrid-gas.The geochemical characteristics of natural gas exhibit a great variations with respect to composition of hydrocarbon,C_6—C_7 light hydrocarbon,isotope and so on.The study shows that the gas in the northern Tarim Basin is mainly originated from high- mature sapropelitic-gas and closely with marine oil,the normal humus-gas is genetically related to the terrestrial oil,while the hybrid-gas has relation to the degree of mixing among the different source gases.