原油的厌氧细菌降解作用及其产物特征

DEGRADATION OF ANAEROBIC BACTERIA IN CRUDE OIL AND ITS PRODUCT PROPERTY

李赞豪 李季 向龙斌 夏遵义 张远成

Li Zanhao Li Ji Xiang Longbin Xia Zunyi Zhang Yuancheng

原油的厌氧细菌降解作用和喜氧降解作用一样普遍存在,但它不仅仅只具破坏作用,而且能再生某些新的烃类,并能形成新的油气藏。我国许多所谓的浅层过渡气实际上是原油厌氧细菌降解作用的结果。原油厌氧细菌降解作用的产物具有甲烷碳同位素轻(δC<-5.5%)、乙烷碳同位素特别轻(δC<-4.0%)和单烃化合物碳同位素为负值异常(δC-3.7%～-5.3%)的特点。塔中地区的天然气至少混有20%以上的菌解甲烷。

It is universal that both the anaerobic bacterial degradation and oxidative bacterial degradation of crude oil exist in the hydrocarbon evelution.They do not only distroy some hydrocarbons,but also reproduce some new hydrocarbons,and even result in new hydrocarbon pools for exploration.A lot of shallow transitional gas pools actually resulted from anaerobic degradation.The products of the anaerobic bacterial degradation of crude oil possess light methane carbon isotope(δC<-5.5%),very light ethane carbon isotope (δC<-4.0%)and the negative anomaly of carbon isotope of separate hydrocarbons (δC<-3.7%～-5.3%).Natural gas produced in central Tarim Basin contains at least 20% bacterial degrated methane.

10.11743/ogg19980105