克百地区二叠系火山岩储层特征及其控制因素分析

Characteristics and controlling factors of Permian volcanic reservoirs in Kebai Area

袁晓光 2 李维锋 2 董宏³ 王涛⁴ 张宝露⁵ 李胜 2

长江大学油气资源与勘探技术教育部重点实验室，湖北 武汉 430100 长江大学地球科学学院，湖北 武汉 430100 中国石油新疆油田公司勘探开发研究院，新疆 克拉玛依 834000 中国石油克拉玛依红山油田有限责任公司，新疆 克拉玛依 834000 长江大学地球环境与水资源学院，湖北 武汉 430100

MOE Key Laboratory of Exploration Technologies for Oil and Gas Resources, Yangtze University, Wuhan 430100, China School of Geosciences, Yangtze University, Wuhan 430100, China Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 834000, China Karamay Hongshan Oilfield Company Limited, PetroChina, Karamay 834000, China College of Earth Environment and Water Resources, Yangtze University, Wuhan 430100, China

克百地区二叠系火山岩储层具有良好油气勘探前景，但缺乏系统研究，对物性控制因素也认识不清。通过最新的岩心、薄片观察及大量物性测试，对其储层特征及物性控制因素等进行研究。结果表明：该火山岩储层岩性主要为安山岩、玄武岩、流纹岩以及火山角砾岩、凝灰岩等；储集空间类型包括原生孔缝及次生孔缝；孔隙结构表现为分选差、孔喉半径小、歪度细；储层具有低孔、低渗、非均质性强等特点。储层物性控制因素分析表明，其物性主要受控于岩性或岩相类型，火山角砾岩及凝灰岩的储集物性相对较好；风化淋滤及溶蚀作用可形成次生孔隙、改善火山岩储集性能；矿物充填作用对火山岩储集物性具有强烈的破坏，是导致玄武岩物性变差的根本原因；构造作用通过形成构造裂缝和不整合面亦可改善火山岩储集物性。二叠系地层中各不整合面以下短距离内的火山角砾岩及凝灰岩储层是未来研究区火山岩油气勘探的首选目标。

The Permian volcanic reservoirs in Kebai Area have good exploration prospects, but systematic research and clear understanding of controlling factors of physical property have not been carried out. With the newest cores, thin section observation and physical property tests, the reservoir characteristics and controlling factors of physical property are researched. The result shows that the lithologies of volcanic reservoirs are basalt, andesite, rhyolite, volcanic breccia and tuff; reservoir space types are of primary pore and secondary pore, structure of pores are of poor sorting, small pore-throat radius and fine crooked degree; physical property is of low porosity, low permeability and strong heterogeneity. The analysis of controlling factors of reservoir physical property shows that reservoir physical property is mainly controlled by the lithology and lithofacies types, among them, the reservoir physical property of volcanic breccia and tuff are relatively better; weathering, leaching and dissolution can form secondary pores of volcanic rocks and improve the reservoir physical property; mineral filling can obviously damage the physical property of volcanic reservoirs, which is the most important factor worsening the physical property of basalt; tectonism can improve the physical property of volcanic reservoirs by forming structural fractures and unconformity surface. After all, the volcanic breccia and tuff under the unconformity surface will be the first target of oil and gas exploration of volcanic reservoirs in future.

10.6056/dkyqt201504008