Fracture development and hydrocarbon accumulation in tight sandstone reservoirs of the Paleogene Huagang Formation in the central reversal tectonic belt of the Xihu Sag, East China Sea

被引:0
作者
Zhou X. [1 ,2 ]
Xu G. [1 ]
Cui H. [1 ]
Zhang W. [2 ]
机构
[1] State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu
[2] CNOOC China Limited, Shanghai Branch, Shanghai
来源
Shiyou Kantan Yu Kaifa/Petroleum Exploration and Development | 2020年 / 47卷 / 03期
关键词
Authigenic illite; Fluid inclusion analysis; Fracture characteristics; Oil and gas charging; Paleogene Huagang Formation; Xihu Sag;
D O I
10.11698/PED.2020.03.03
中图分类号
学科分类号
摘要
By using thin section identification, cathodoluminescence, major and trace elements and fluid inclusion tests and authigenic illite dating, based on observation of core cracks, combined with the microscopic characteristics and imaging logging characteristics of fractures, the stages of the fractures in the Huagang Formation of the central reversal tectonic belt of the Xihu Sag in the East China Sea, and the matching relationship between the fracture development stages and the oil and gas charging stages are clarified. There are diagenetic fractures and tectonic fractures in the reservoirs of the Huagang Formation in the study area. The diagenetic fractures developed during the diagenetic stage of the reservoirs and have less effect on oil and gas migration and transport. The tectonic fractures are divided into three stages based on tectonic movements controlling the fractures and their relationships with hydrocarbon charging: The first stage of fractures was generated in the early stage of the Himalayan Movement-Longjing Movement (12-13 Ma ago), when the tectonic stress caused the sutures and shale strips to twist, deform, and break. Tectonic microfractures generated in this period had short extension, narrow width, and poor effectiveness, and had little effect on oil and gas migration and transport. The second stage of fractures came up during the middle-late period of Himalayan Movement-Longjing Movement (9-12 Ma ago), when tectonic movements caused the development of tectonic fractures in the central reversal tectonic belt, these fractures are of large scale, long extension, and good effectiveness, and matched with the first stage of large scale oil and gas charging (9-12 Ma ago), so they play an important role in oil and gas migration, transportation, and accumulation. The third stage of fractures were created from Himalayan Movement-Okinawa Trough movement to the present day (0-3 Ma ago), the fractures are tectonic ones developing successively; matching with the second stage (0-3 Ma ago) of large-scale oil and gas charging, they created conditions for continuous natural gas migration and transportation. All these prove that the development of reservoir fractures in the Huagang Formation of Xihu Sag can provide seepage space and continuous and effective channels for efficient migration and accumulation of oil and gas. © 2020, The Editorial Board of Petroleum Exploration and Development. All right reserved.
引用
收藏
页码:462 / 475
页数:13
相关论文
共 35 条
[1]  
DAI Jinxing, NI Yunyan, WU Xiaoqi, Tight gas in China and its significance in exploration exploitation, Petroleum Exploration and Development, 39, 3, pp. 257-264, (2012)
[2]  
Geological evaluating methods for tight sandstone gas: GB/T 30501-2014, (2014)
[3]  
YAO Cheng, HE Zhiqiang, HE Yu, Et al., Study on the developing stage of Ordovician fractures in Tahe southern subsalt area, Journal of Chongqing University of Science and Technology(Natural Sciences Edition), 15, 1, pp. 9-30, (2013)
[4]  
ZHU Mengyue, QIN Qirong, LI Hu, Et al., Development characteristics and controlling factors of shale fractures in the Longmaxi Formation in DS area, southeast Sichuan, Petroleum Geology and Recovery Efficiency, 24, 6, pp. 54-59, (2017)
[5]  
LIU Ling, TANG Dazhen, XU Hao, Development of fractures and its effects on gas accumulation in the upper Paleozoic tight sandstone reservoirs of the Linxing Block, Geological Journal of China Universities, 25, 3, pp. 457-465, (2019)
[6]  
ZHANG Shaoliang, ZHANG Jianpei, TANG Xianjun, Et al., Geometry characteristic of the fault system in Xihu Sag and its formation mechanism, Marine Geology & Quaternary Geology, 34, 1, pp. 87-94, (2014)
[7]  
YANG Caihong, GAO Zhaohong, JIANG Yiming, Et al., Reunderstanding of clastic rock sedimentary facies of Eocene Pinghu Formation in Pinghu Slope of Xihu Sag, Journal of Oil and Gas Technology, 35, 9, pp. 11-14, (2013)
[8]  
YANG Chao, LI Deyong, Restoration and settlement of Xihu sag based on 3D seismic data, West-China Exploration Engineering, 29, 2, pp. 85-88, (2017)
[9]  
JIANG Liang, Proceedings of oil and gas resources exploration in the East China Sea shelf basin, (2004)
[10]  
DAI Liming, Dynamic mechanism and numerical simulation of genesis of the East China Sea shelf basin, (2010)