水进型扇三角洲优质储层分布规律探讨

High quality reservoir distribution research of the Beibu Gulf Basin in transgression fan deltas

始新统流沙港组一段是南海北部湾盆地主要的含油层系之一,主要发育断陷湖盆水进型扇三角洲沉积储层,这种类型的储层具有砂体分布范围有限,产能变化大,非均质性强的特点,如何寻找优质储层是研究难点之一。本文从沉积微相成因分析的研究入手,总结不同期次不同沉积微相的特点,进一步将主要的水下分流河道微相根据研究需要细分为近物源端、远物源端和分支水道,在此基础上对物性影响因素进行统计分析,揭示在不同沉积微相影响物性主控因素,最后对研究区优质储层的空间分布特征和规律进行探讨,有效指导该油田下一步的开发工作。

The Weizhou A oil field is one of production oil fields of northern South China Sea,Beibuwan Basin.The Paleogene Eocene Liushagang reservoir is the main oil-bearing stratum which for the current has been put into development.How to find high-quality reservoir is one of the difficulties faced by the oil field development in transgression fan deltas in Rifted basin.In this paper,by starting from the information of Seism and sedimentary microfacies,mark off three different types of transgression fan deltas and sum up sedimentary microfacies characteristic.On this basis,we count and analyze affecting factors of physical property.In order to reveal the main-affecting factor in different lithology and sedimentary microfacies.The geological knowledge base of the distribution of the sand in this oilfield is established,the characteristics and the regulation of the distribution of favorable reservoirs in the study area has been discussed,which are the guidance of the oil-field development work.