Lithofacies characteristics and genetic model of shallow lacustrine fine-grained sediments and its geological significance for shale oil in the Qiketai Formation in the Shengbei subsag, Turpan-Hami basin

被引：0
|
作者：
Li T. [1 ,2 ]
Huang Z. [1 ]
Zhang Y. [3 ]
Wang R. [1 ]
Zhang H. [3 ]
Zhou Z. [4 ]
机构：
[1] College of Geosciences, China University of Petroleum (Beijing), Beijing
[2] PetroChina Southwest Oil &Gasfield Company, Research Institute of Exploration and Development, Chengdu
[3] PetroChina Tuha Oilfield Company, Exploration and Development Research Institute, Hami
[4] PetroChina Yumen Oilfield Company, Exploration and Development Research Institute, Jiuquan
来源：
Dizhi Xuebao/Acta Geologica Sinica | 2021年 / 95卷 / 12期
关键词：
Fine-grained sedimentary rocks; Lithofacies characteristics; Sedimentary environment; Shale/tight oil; Shengbei subsag;
D O I：
10.19762/j.cnki.dizhixuebao.2021173
中图分类号：
学科分类号：
摘要：
In this study, based on results of core observations, thin sections, X-ray diffraction and scanning electron microscopy (SEM), combined with inorganic geochemical indicators, the lithofacies characteristics and sedimentary environment of shallow lacustrine fine-grained rocks in the second Member of Qiketai Formation (J2q2) are studied. The sedimentary genetic model of shallow lacustrine fine-grained rocks was established, and the significance of shale oil/tight oil reservoirs is also analyzed. The results show that the fine-grained sedimentary rocks in the study area have complex mineral composition and sedimentary structure, and the content of organic matter varies greatly.Based on the mineral composition, sedimentary structure and organic matter characteristics, fine-grained rocks of J2q2 were divided into 11 lithofacies types, which were mainly multi-components mixed lithofacies, each of which had a variety of sedimentary structures, including massive, granular and laminated types. Organic matter-bearing massive felsic fine-grained mixed/sedimentary rock lithofacies, organic matter-bearing massive carbonate fine-grained mixed/sedimentary rock lithofacies, and organic matter-bearing massive argillaceous fine-grained mixed/sedimentary rock lithofacies prevail, with a small amount of organic matter-rich laminated carbonate fine-grained mixed/sedimentary rock lithofacies and granular carbonate fine-grain mixed/sedimentary rock lithofacies.Under the conditions of arid paleoclimate, high paleosalinity, relatively deep water column and weak terrigenous clastic supply, chemical and biochemical changes in the water column of lacustrine basin caused development of carbonate fine-grained mixed/sedimentary rocks.The lithofacies in different sedimentary environments frequently overlap and alternate in vertical direction, which can be recognized as four types of lithofacies assemblages. They were formed in shallow carbonate granular beaches-lacustrine bays assemblages, lacustrine bays and lime mud flats assemblages, lime mud and sand-mud flat assemblages, mixed sedimentary beach bar and shallow lake mud assemblages, respectively.Finally, based on the research of the lithofacies types, characteristics, sedimentary environment and vertical evolution sequence of fine-grained rocks, the sedimentary model of the shallow lacustrine fine-grained rocks in the J2q2 was established. The fine-grained rocks have moderately high hydrocarbon generation potential, and the fine-grained rocks with high carbonate content develop carbonate intercrystalline pores and microfractures. Moreover, the fine-grained rocks are suitable for fracturing because of high brittle mineral content. They have favorable conditions for shale oil and tight oil accumulation, and are significant for exploration. © 2021, Science Press. All right reserved.
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页码：3869 / 3884
页数：15
相关论文
共 31 条
  • [1] Aplin A C, Macquaker J S H., Mudstone diversity:origin and implications for source, seal, and reservoir properties in petroleum systems, AAPG Bulletin, 95, 12, pp. 2031-2059, (2011)
  • [2] Chen Xuan, Liu Xiaoqi, Wang Xuechun, Wang Xuechun, Ma Qiang, Liu Juntian, Gong Xin, Yang Xiaodong, Shi Jiangfeng, Bai Guojuan, Formation mechanism and distribution characteristics of Lucaogou shale oil reservoir in Santanghu basin, Natural Gas Geoscience, 30, 8, pp. 1180-1189, (2019)
  • [3] Yue Feng, Zhilong Huang, Hua Zhang, Jian Wang, Yazhong Peng, Diamictite tight reservoir characterization of Qiketai Formation Member-2 in the Shengbei depression of Tuha basin, Special Oil and Gas Reservoirs, 26, 5, pp. 56-63, (2019)
  • [4] Chenggang Huang, Wang Jiangong, Lirong Wu, Xianglong Ni, Yang Shen, Liangyu Wu, Characteristics of Paleogene lacustrine carbonate reservoirs and oil-bearing property analysis:a case study of the Yingxi area of western Qaidam basin, Journal of China University of Mining & Technology, 46, 5, pp. 1102-1115, (2017)
  • [5] Hua Huang, Wei Peng, Xuebin Du, Sedimentary environment and characteristics of the Lowersegment of Xingouzui Formation in Jiangling depression, Journal of Yangtze University (Natural Science Edition), 16, 4, pp. 8-16, (2019)
  • [6] Jones B, Manning D A C., Comparison of geochemical indices used for the interpretation of palaeoredox conditions in ancient mudstones, Chemical Geology, 111, pp. 111-129, (1994)
  • [7] Jarvie D M, Hill R J, Ruble T E, Pollastro R M., Unconventional shale-gas systems: the Mississippian Barnett shale of north-central Texas as one model for thermogenic shale-gas assessment, AAPG Bulletin, 91, 4, pp. 475-499, (2007)
  • [8] Zaixing Jiang, Chao Liang, Jing Wu, Jianguo Zhang, Wenzhao Zhang, Yongshi Wang, Huimin Liu, Xiang Chen, Several issues in sedimentological studies on hydrocarbon-bearing fine-grained sedimentary rocks, Acta Petrolei Sinica, 34, 6, pp. 1031-1039, (2013)
  • [9] Ji Youliang, Dade Ma, Jianqin Xue, Peng Wang, Yanxiong Wu, Li Zeng, Li Jin, Sedimentary environments and sedimentary model of carbonate rocks in the Cenozoic lacustrine basin, western Qaidam basin, Journal of Palaeogeography, 19, 5, pp. 757-772, (2017)
  • [10] Wenhou Li, Lifa Zhou, Yiquan Liu, Shijun Liang, Daojiang Long, Evolution of sedimentary framework and environment of Turpan-Hami basin, Xinjiang Petroleum Geology, 18, 2, pp. 135-141, (1997)
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