重庆马槽坝-黑楼门地区上石炭统黄龙组白云岩储层类型及其控制因素

Types and controls on the dolostone reservoirs in the Upper Carboniferous Huanglong Formation, Macaoba-Heiloumen region, Chongqing

关键词:  黄龙组  白云岩  储层物性  成岩作用  沉积相

Key words:  Huanglong Formation  dolostone  physical property  diagenesis  sedimentary facies

摘要:

根据钻井岩心、薄片、物性等数据资料,对四川盆地东部马槽坝-黑楼门地区白云岩储层特征进行分析,并探讨沉积相及成岩作用对储层形成的控制作用。研究区白云岩储层的岩石类型主要为颗粒白云岩、微晶白云岩、粉-细晶白云岩。储集空间以次生粒间及粒内溶孔为主,并伴生有超大溶孔。研究区黄龙组储层总体上属于低孔低渗储层,以小孔-中细喉组合为主。白云石化作用、重结晶作用、破裂作用、古岩溶作用是有利于储层发育的成岩作用,其中白云石化作用是最普遍也是最重要的成岩作用。粒屑浅滩、潮道是有利于储层发育的沉积环境。

Abstract:

The present paper deals, on the basis of cores, thin sections and physical properties, with the types and controls of sedimentary facies and diagenesis on the dolostone reservoirs from the Huanglong Formation in the Macaoba-Heiloumen region, eastern Sichuan Basin. The dolostone types are composed of grainy dolostone, micritic dolostone, silty to fine-grained dolostone. The reservoir spaces consist of dominant secondary intergranular and intragranular solution openings and associated superlarge solution openings. The dolostone reservoirs from the Huanglong Formation generally belong to the low-porosity and low-permeability reservoirs with micropores and moderate-fine pore throats. The diagenesis favourable for the development of the dolostone reservoirs includes dolomitization, recrystallization, cataclasis and palaeokarstification, of which the dolomitization is wide-spread and most important diagenesis. The shoals and tidal channels are interpreted as the favourable sedimentary environments for the development of the dolostone reservoirs in the study area.