吐哈盆地胜北地区七克台组致密储层储集空间类型及形成机理  

Reservoir Space Types and Formation Mechanism of Tight Reservoir of Qiketai Formation in Shengbei area,Tuha Basin

作　　者：赵浩旭 郭岭[1] 方泽鑫 Zhao Haoxu;Guo Ling;Fang Zexing(State Key Laboratory of Continental Dynamics,Northwest University,Xi'an,Shaan'xi,710069,China)

机构地区：[1]西北大学大陆动力学国家重点实验室,陕西西安710069

出　　处：《新疆地质》2023年第1期55-60,共6页Xinjiang Geology

基　　金：国家自然科学基金项目海洋古沉积环境特征序列演化的黑色页岩记录(41302076)资助。

摘　　要：为深入了解吐哈盆地胜北地区致密油藏储层特征及形成条件,在分析大量测试资料的基础上,对研究区中侏罗统七克台组致密储层储集空间及其形成机制进行了研究。结果表明,七克台组致密储层主要岩石类型为粉砂岩、粉砂质泥岩、灰质泥岩和少量泥质灰岩。粉砂岩中矿物成分以石英为主,次为长石、粘土矿物和少量碳酸盐矿物;填隙物以自生矿物为主,方沸石、杂基含量较多。孔隙类型主要为粒间孔隙、溶蚀孔隙和微裂缝,粒间孔隙主要形成于同沉积时期,而溶蚀孔隙主要形成于中成岩阶段的燕山运动的Ⅱ-Ⅲ幕时期,裂缝主要形成于喜马拉雅运动时期。研究发现,碳酸盐矿物含量与孔隙度、渗透率具较好的正相关性,成岩作用主要有压实作用、胶结作用和溶蚀作用。压实作用是储层致密化的主要原因,而溶蚀作用和破裂作用等对研究区储层起到改善的作用。In order to understand the characteristics and formation conditions of tight oil reservoirs in Shengbei area of Tuha Basin,Based on the analysis of a large number of test data,the reservoir space and formation mechanism of tight reservoirs in Qiketai Formation of middle Jurassic in the study area are studied.The results show that the main rock types in the tight reservoir of Qiketai Formation are siltstone,silty mudstone,calcareous mudstone and a small amount of argillaceous limestone.The mineral composition of siltstone is mainly quartz,followed by feldspar,clay minerals and a small amount of carbonate minerals.The interstitial materials were mainly authigenic minerals with more zeolite and matrix content.Pore types are mainly intergranular pore,dissolution pore,and micro-fracture.The intergranular pores were mainly formed during the syndepositional period,while dissolution pores mainly formed in the stage of Yanshan movementⅡ-Ⅲperiod.The fractures formed mainly during the Himalayan movement.It is found that the content of carbonate minerals is positively correlated with porosity and permeability.Type of diagenesis mainly includes compaction,cemen-tation and dissolution.Compaction is the main cause of reservoir densification,while dissolution and fracture play an important role in improving the reservoir in the study area.

关 键 词：致密储层 微裂缝 孔隙 成岩作用 吐哈盆地 

分 类 号：P941.75[天文地球—自然地理学]