缝洞型碳酸盐岩油藏古溶洞系统与油气开发——以塔河碳酸盐岩溶洞型油藏为例

A study of the paleo-cavern system in fractured-vuggy carbonate reservoirs and oil/gas development——taking the reservoirs in Tahe oilfield as an example

以塔河奥陶系碳酸盐岩缝洞型油藏为原型,厘定了古溶洞系统的概念与特征,探讨了其形成、演化、改造以及对油藏的分隔作用,提出了古溶洞系统的垮塌充填-断裂体系是造成油藏分隔化作用的主要因素。针对该类油藏由于喀斯特作用与构造作用所造成的缝洞储集体非均质性特征,认为其油藏描述应按照系统性、层次性思路,分岩溶体系(古溶洞系统)与油藏体系(缝洞单元)两个级次来进行。与此同时,按照对喀斯特油藏描述调整后的思路与技术方法对研究区古溶洞系统与开发井位部署之间关系进行了描述,取得了良好效果。

A study of the Ordovician fractured-vuggy carbonate reservoirs in the Tahe oilfield is carried out to determine the concept and features of paleo-cavern systems in these reservoirs. Also included in the study are the formation, evolution, and deformation of these systems as well as their role in compartmentalization of reservoirs. The study points out that the compartmentalization of these reservoirs is mainly caused by collapse, filling, and fracturing processes of the pale-cavern systems. It is therefore suggested that these heterogeneous reservoirs formed by karstification and tectonic movements shall be described systematically and hierarchically from a karst system level （paleo-cavern system） and reservoir level （fracture-rug unit）. The idea is applied to the study area and gains positive results.