四川盆地栖霞组储层类型及形成控制因素

Reservoir Types and Control Factors of the Xixia Formation in the Sichuan Basin

四川盆地栖霞组是目前盆地油气勘探的重要层位,前人已对其开展过大量研究,但在诸多方面仍存在争议,不利于栖霞组进一步勘探开发工作。本文在调研盆地栖霞组相关文献的基础上,结合川中地区栖霞组勘探实践中相关地球化学实验结果,对前人的研究进行归纳和总结,包括层序地层格架、沉积相带、储层类型、储层成因、白云石化作用类型等。前人认为盆地栖霞组储层类型主要为晶粒白云岩储层和溶洞型灰岩储层,但在层序地层格架、沉积相带和储层成因方面有不同观点。其中,前人大多将栖霞组划分为1个或2个三级层序,在沉积相带的划分上有碳酸盐岩台地、碳酸盐岩缓坡和二者兼具等观点,认为栖霞组白云岩可能为埋藏、热液、渗透回流或多种白云石化作用叠加形成,白云岩储层成因则有热液溶蚀作用改造、有利相带叠加溶蚀作用等多种观点。

The Qixia Formation in the Sichuan basin is an important horizon for oil and gas exploration at present.A great deal of research has been done on it,but there are still disputes in many aspects such as sequence stratigraphic framework,sedimentary facies zone,reservoir type,reservoir genesis and dolomitization type.This paper summarizes the previous research results.The reservoir types of the Qixia Formation are crystalline dolomite reservoir,dissolution pore-karst cave dolomite reservoir and karst cave limestone reservoir.Controlling factors of reservoir development are favorable grain bank sedimentary facies zone,dolomitization and dissolution.