影响准噶尔盆地碎屑岩储层储集性的主要因素

准噶尔盆地自石炭纪以来经历了海西期、印支期、燕山期和喜马拉雅期等多次构造运动 ,多次的抬升剥蚀和再沉降过程 ;从石炭系至第三系均有油气储层发育 ,储层岩性有碎屑岩、火山碎屑岩、火山岩。石炭系及下二叠统主要发育一套陆相、海陆交替相、泻湖相及火山岩相地层 ,为正常碎屑岩、火山岩—火山碎屑岩储层 ,其中 ,碎屑岩储层成岩阶段多为晚成岩C段 ,孔隙类型主要为裂缝 +次生孔 ,影响储层储集性的主要因素为构造运动、岩性 ;中二叠统以上地层主要为一套沉积作用形成的陆相碎屑岩地层 ,为正常碎屑岩储层 ,储层孔隙类型主要为原生孔和次生孔 ,影响因素主要为埋藏深度、沉积作用、粘土矿物脱水、烃源岩演化及构造运动 ,不同成岩阶段 ,其储层的孔隙类型及主要影响因素不同。另外 ,沉积时的古气候条件及风化淋滤作用也是影响储层储集性的重要因素之一

ANALYSIS ON DOMINANT FACTORS AFFECTING THE RESERVOIR PROPERTIES OF CLASTIC BED IN JUNGGAR BASIN

Since Cretaceous Period, Junggar Basin has undergone multitudes of elevated denudation and resettlement processes caused by Hercynian, Indosinian, Yanshan and Himalayan tectonic movements. Hydrocarbon reservoirs were developed from Cretaceous to Tertiary, with the lithology of reservoir ranging from clastic, volcanic rocks to pyroclastic rocks. A set of continental, marine-continental alternating phase, lagoon and volcanic phase formations developed in Cretaceous and Lower Permian bed, constituting normal clastic, volcanic and pyroclastic reservoirs. Among them, the clastic reservoirs were formed during C late diagenetic stage, with the dominant porosity types being original and induced porosity, while the dominant factors influencing the reservoir properties are tectonic movement and lithology. The formations overlying Middle Permian bed is a set of continental clastic rock reservoirs formed under sedimentation , constituting normal clastic reservoirs, with the major reservoir porosity types being primary and secondary, while the dominant affecting factors are burial depth, sedimentation, dehydration of clay minerals, evolution of source rocks and tectonic movements. The reservoir porosity types and their major influencing factors differ in various diagenetic stages. In addition, palaeoclimatic conditions during sedimentation , weathering and leaching processes are also important factors affecting the reservoir properties.