顺北油田1号断裂带奥陶系原油地球化学特征

Geochemical characteristics of Ordovician crude oil in the No.1 fault zone of Shunbei oilfield

通过原油物理性质、地球化学特征分析,结合钻井、生产、温压测试等资料对顺北1号断裂带中下奥陶统油气地球化学特征进行了研究。结果表明,顺北1号断裂带油藏为高气油比的未饱和挥发性油藏,形成于偏强还原沉积环境;属于以藻类为母质的腐泥型,干酪根为Ⅰ型。生成的海相原油处于高演化成熟阶段,原油的生物标志化合物与玉尔吐斯黑色页岩具有较好的相似性,来源于寒武系烃源岩;油气以垂向运移为主,断裂是主要的运移通道。

Through the analysis of the basic physical properties and geochemical characteristics of crude oil,combined with the drilling data,producing data and temperaturepressure testing data,the geochemical characteristics and hydrocarbon accumulation model of lower-middle Ordovician in No.1fault zone of Shunbei oilfield were studied.The results indicate the No.1fault zone of Shunbei oilfield is an unsaturated volatile reservoir with high gas-oil ratio and it was formed in the partial strong reduction sedimentary environment.The crude oil belongs to the marine crude oil which was formed by the evolution of the aprotic typeⅠkerogen.The marine crude oil generated is in the stage of high evolution and maturity.The biomarker of crude oil is similar to the black shale of Yultus,which is derived from Cambrian source rock.The migration path of oil and gas is dominated by vertical migration and the fracture is the main migration channel.