摘要
鄂尔多斯盆地长6～长8段致密油是中国典型的致密油分布区。源储紧密接触是致密油的典型特征与成藏条件。致密油层非均质性强,石油运移多以垂向短距离为主。已有研究表明,储层非均质性是影响鄂尔多斯盆地合水地区剩余油分布的重要因素,但是目前对合水地区储层含油性影响因素的研究很少。通过分析合水地区长6～长8段源储结构及其与含油性的关系,研究其对储层含油性的控制作用。结果表明:合水地区长6～长8段源储结构复杂,长7段为源储一体型岩性组合,可细分为源夹储型、源储互层型与储夹源型3种类型,长6与长8段为研究区主要储层,与烃源岩形成邻源型岩性组合,细分为源储接触型、源储过渡型与源储间隔型3种类型;长7段源夹储型岩性组合的含油性最好,长6与长8段源储接触型岩性组合的含油性最好,最有利于致密油聚集;长6～长8段形成干酪根网络→孔隙+微裂缝型、干酪根网络+构造裂缝→孔隙+微裂缝型两种石油运移通道组合,为致密油充注提供有利的通道网络。
Chang-6-Chang-8 members of Ordos Basin are typical tight oil distribution area in China. Tight contact between source and reservoir is a typical characteristic and reservoir forming condition of tight oil. Tight oil layers are highly heterogeneous, and oils mostly migrate with short vertical distances. Previous studies show that the heterogeneity of reservoir is an important factor affecting the distribution of remaining oil in Heshui area of Ordos Basin. However, there are few studies on the influencing factors of reservoir oil-bearing property. The source-reservoir structure of Chang-6-Chang-8 members in Heshui area and its relation with oil-bearing property were analyzed, and the controlling effect on oil-bearing property was studied. The results show that the source-reservoir structure is complicated in Chang-6-Chang-8 members of Heshui area;the lithological association types of source-reservoir in Chang-6-Chang-8 members are self-sourced oil reservoirs, and the source rocks are closely adjacent to the reservoirs, and can be subdivided into six types, including source rocks interbedded by reservoirs, equally interbedded between source rocks and reservoir, reservoirs interbedded by source rocks, direct contact between source rocks and reservoir, gradual transition of source rocks and reservoirs, and source rocks separated from reservoirs;the type of source rocks interbedded by reservoirs shows the best oil-bearing property in Chang-7 member, whereas the type of direct contact between source rocks and reservoir shows the best oil-bearing property in Chang-6 and Chang-8 members, which are most favorable for tight oil accumulation;the oil migration pathway combination of kerogen network→organic pore+structural fracture develops in source rocks of Chang-7 member, and the oil migration pathway combination of kerogen network+structural fracture→pore+microfracture develops in reservoirs of Chang-6 and Chang-8 members, providing favorable migration network for tight oil charging.
作者
姚泾利
曾溅辉
罗安湘
杨智峰
邓秀芹
YAO Jing-li;ZENG Jian-hui;LUO An-xiang;YANG Zhi-feng;DENG Xiu-qin(Research Institute of Exploration and Development, Changqing Oilfield Company, PetroChina, Xi'an 710018, Shaanxi, China;State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China;College of Geosciences, China University of Petroleum, Beijing 102249, China;Postdoctoral Research Workstation, Xinjiang Oilfield Company, PetroChina, Karamay 834000, Xinjiang, China)
出处
《地球科学与环境学报》
CAS
北大核心
2019年第3期267-280,共14页
Journal of Earth Sciences and Environment
基金
国家自然科学基金项目(41330139)
关键词
源储结构
岩性组合
通道类型
含油性
致密储层
裂缝
合水地区
鄂尔多斯盆地
source-reservoir structure
lithological association
type of migration pathway
oil-bearing property
tight reservoir
fracture
Heshui area
Ordos Basin
