鄂尔多斯盆地镇原地区长8油层组油气成藏模式

探讨鄂尔多斯盆地镇原地区油气充注特征与油藏主控因素,以及油气聚集规律与成藏模式。运用成藏动力学,以典型油气藏或出油点解剖为基础,以流体来源及其流动样式为核心,采用精细油源对比、流体包裹体技术和油气运移路径示踪技术等方法。结果表明长8油层组为岩性或构造-岩性油藏,油气主要来源于长7段优质烃源岩;主要存在2期原油连续充注过程(±130 Ma B.P.和±105 Ma B.P.),第二期为主充注期;流体存在明显的从上至下的垂向运移指向,进一步证实"上生下储、高压驱动、裂缝与砂体输导、多点充注、近源成藏"的模式特征。

Hydrocarbon accumulation modes of Chang 8 oil reservoir group in Zhenyuan area,Ordos Basin,China

This paper approaches the injecting characteristics and the main controlling factors of oil accumulation,the oil and gas accumulation regularity,and the hydrocarbon accumulation mode in the Zhenyuan area,Ordos Basin,by using the theory of the hydrocarbon accumulation dynamics,based on the analysis of the typical oil and gas reservoir/oil exit,taking the fluid source and its flow pattern as the core,and using the oil source correlation,fluid inclusion and tracking hydrocarbon migration path techniques.The results indicate that Chang 8 oil reservoir group is a lithologic oil accumulation or a structural-lithologic oil accumulation.There exist two stages of consecutive crude oil injecting processes(±130 Ma B.P.,±105 Ma B.P.)and the second stage is the main injecting stage.The fluid obviously and vertically migrates from top to bottom.This shows the characters of the hydrocarbon accumulation modes,such as injection migration,high-pressure drive,and near-source hydrocarbon accumulation.