优质烃源岩对鄂尔多斯盆地延长组石油聚集的控制作用  

Control effect of high-quality source rocks on petroleum accumulation in Yanchang Formation,Ordos Basin

作　　者：白玉彬[1] 赵靖舟[1] 方朝强[1] 刘鹏[1] 

机构地区：[1]西安石油大学油气资源学院,陕西西安710065

出　　处：《西安石油大学学报（自然科学版）》2012年第2期1-5,117,共5页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金："十一五"国家科技支撑计划(编号:2007BAB1701);西安石油大学青年科技创新基金(编号:2011QN004)

摘　　要：三叠系延长组是鄂尔多斯盆地最主要的含油层系,主力烃源岩为长7段中下部的"张家滩页岩",累计厚度大,分布面积约5×104km2.烃源岩地化指标分析结果表明,张家滩页岩残余有机碳质量分数一般为6%～14%,有机质类型主要为腐殖-腐泥型,分布范围内烃源岩均已达到成熟,为一套优质烃源岩.勘探实践证实,烃源岩的分布和质量对石油富集具有重要的控制作用,这主要与延长组构造背景、储层致密性及后期保存条件有关.延长组长6段及其以上油藏与分布在陕北斜坡西部已发现的长8油藏平面上大面积准连续分布,且均分布在长7优质烃源岩展布范围内,因此,张家滩页岩分布范围控制了延长组长6及其以上地层油藏和西北、西南部长8油藏分布.Triassic Yanchang Formation in Ordos Basin is the main oil-bearing layers.'Zhangjiatan shale' located in the lower part of Chang 7 member is the main source rocks,which is of great cumulative thickness and large distribution area of about 5 ×104 km2.The analysis of geochemical index of the shale shows that it is a good source rocks,in which the residual organic carbon content is generally 6% ~ 14%,main organic matter is humic-sapropel type.The source rocks in the distribution range have reached to mature,and they are high-quality source rocks.Exploration practice confirmed that the quality and the distribution of source rock have important control role on petroleum accumulation,which is related mainly with the tectonic setting,reservoir density and preservation conditions of Yanchang Formation.The oil reservoirs in Chang 6 and above it,as well as oil reservoir in Chang 8 in the west of the northern Shaanxi slope distribute in the range of high-quality source rocks in Chang 7,which just verifies the control effect of the quality and distribution of source rocks on the petroleum accumulation.

关 键 词：鄂尔多斯盆地 三叠系 延长组 烃源岩 成藏 

分 类 号：TE122[石油与天然气工程—油气勘探]