含水油藏一般见于中-低孔、低-特低渗透率碎屑岩储层中.严重的非均质性是其突出特点.微观上,碎屑岩内部具有赋存液态石油的自流孔喉系统和饱和着原生地层水的滞流孔喉系统双重孔隙结构.其中,自流孔喉系统中含有自由水;滞流孔喉系统中主要赋存有微细孔隙水、微孔隙水、死孔隙水、和分子结合水.滞流孔喉系统在岩石孔隙体积中占有相当大的比例,制约着油水的产出情况,并导致了多数含水油藏的含油饱和度不足50%.含水油藏(层)形成的地质条件主要与二连中生界裂谷盆地群碎屑岩结构、组分成熟度过低及因成岩作用而物性急剧变差有关.在当前经济和技术条件下,含水油藏尚处于商业开采边沿,因此,应依据岩心含油、岩心滴水试验、气测录井、薄片鉴定、物性分析、压汞试验、核磁共振测量、油层测试等方面的特征,尽早对含水油藏(层)进行动态识别与评价,以避免实物工作量的无效投入.

The Suqiao buried hill hydrocarbon is a representativ e's example of both primary reservoir in Paleozoic and breakthrough of explorati on history in coal-formed oil/gas fields at North China plateform in early 80 y ears.It was the focus reservoir made more attention by our domestic petroleum g eologists at that time.Based on the study of geological structures and potential reservoir conditions of Wenan slope Baxian depression,author concludes that h ydrocarbons of Suqiao reservoirs were mainly generated by lacustrine claystone o f Tertiary in Baxian depression,perhaps only few hydrocarbon generated by coal b eds.This paper also analyzed some public papers in which conclusions were the Su qiao reservoir generated from coal beds according to both the geochemistry and s o called evidents of coal formed hydrocarbon studies.Finally,the paper said so f ar there are no real strong evidents support to the coal formed gas and for some key items there are no satisfactorily explanation.