鄂东南通山半坑志留系古油藏成藏解剖

Analysis of the hydrocarbon accumulation process of the Silurian paleo-pool in Tongshan Bankeng,the southeastern Hubei Province

鄂东南通山半坑志留系古油藏具有复杂叠合盆地的成藏特征,油源对比表明,古油藏具有混源特征,油源主要来自下寒武烃源岩,部分来自上震旦统和下志留统烃源岩.对半坑古油藏成藏演化分析发现,印支期及以前的构造演化控制原生油气藏的形成与分布,而燕山运动则为古油藏破坏的主要因素.结合研究区的构造演化、埋藏和生排烃史特征探讨了通山古油藏成藏模式,认为古隆起与岩性岩相带控制原生油藏→次生构造油气藏→原油热裂解古气藏→现今残余固体沥青矿藏的形成.

Silurian paleo-pool in Tongshan Bankeng,the southeastern Hubei Province is characterized by the accumulation of superimposed basin.Oil-source correlation analysis shows that the paleo-pool is a mixed-source oil reservoir.Its main oil source is from Lower Cambrian hydrocarbon source rock,and a part comes from Upper Sinian and Lower Silurian hydrocarbon source rock.The hydrocarbon accumulation evolution of the paleo-pool indicates that tectonic evolution controls the formation and distribution of the primary oil-gas pool during Indo Chinese epoch and the past.However,the Yanshan Movement is a main factor of disintegrating the paleo-pool.According to the characteristics of the tectonic evolution,burial history,hydrocarbon generation history and hydrocarbon expulsion history,it is held that the evolution of the paleo-pool is from the primary oil pool controlled by paleo-uplift,the lothological and lithic facies belt,to the secondary structural oil-gas pool,to the gas pool formed by crude oil thermal cracking,to present residual asphalt reservoir.