双河油田核桃园组三段储层孔隙结构特征

PORE STRUCTURE AND ITS ORIGIN IN THE THIRD MEMBER OF HETAOYUAN FORMATION IN SHUANGHE OILFIELD

邸世祥 吴频 李建武

Di Shixiang Wu Pin Li Jianwu

早第三纪早期,由于基岩块断下沉,泌阳凹陷开始形成,接受了一套厚约8000米的巨厚沉积。下第三系核桃园组第三段就是其中一个最主要的生、储油岩系(简称核三段)。本文根据该凹陷的主力油田之一—双河油田106块储层岩样的压汞实验、铸体薄片观测及少数样品的电镜扫描成果,并参考前人有关资料,对孔隙结构特征及其成因作一初步探讨。

The 3rd Member of Hetaoyuan Fm constituting the reservoir of the Shuanghe Oilfield in the Biyang depression is represented by coarse clastics from rapid deposition.Pore spaces developed here are mainly of intergranular and corrosive types,and porosity in matrix is rare.There are four grades of pore space,from good to bad,as defind in this paper.However,majority of these pore spaces is of the good ones.The pore structure of reservoir is clearly improved due to the extensive development of secondary corrosive pore spaces.The development of secondary porosity is related both to rapid accumulation,poor maturity and lower compaction caused by earlier calcareous infilling andsubsequent cementation,and to the generation of water and carbon dioxde insource rocks during formation of hydrocarbons,These source rocks being coex-isted and interfingered with reservoirs contain mainly transitional types of kero-gen within a depth favourable to oil and gas generation,so the water and carbon dioxide generated inevitably would react with the early infilled carbonates and other minerals in adjacent reservoir rocks resulting in greater amount of secondary porosity.The development of the secondary porosity might also related to the structure of coarse grained rocks of the reservoir proper.

10.11743/ogg19840307