A quantitative study of the scale and distribution of tight gas reservoirs in the Sulige gas field, Ordos Basin, northwest China

作     者：Chao LUO Ailin JIA Jianlin GUO Qing TIAN Junlei WANG Hun LIN Nanxin YIN Xuanbo GAO Chao LUO;Ailin JIA;Jianlin GUO;Qing TIAN;Junlei WANG;Hun LIN;Nanxin YIN;Xuanbo GAO

作者机构：Chongqing University of Science and TechnologyChongqing 401331China Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil and Gas Reservoirs in West China(Ministry of Education)Xi’an Shiyou UniversityXi’an 710065China Research Institute of Petroleum Exploration and DevelopmentPetroChinaBeijing 100083China Zhejiang Ocean UniversityZhoushan 316022China 

出 版 物：《Frontiers of Earth Science》 (地球科学前沿（英文版）)

年 卷 期：2021年第15卷第2期

页      面：457-470页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 0708[理学-地球物理学] 0704[理学-天文学] 

基　　金：financially supported by the PetroChina Innovation Foundation(No.2019D-5007-0210) National Natural Science Foundation of China(Grant Nos.51904050、41902153) the Chongqing Natural Science Foundation Project(Nos.cstc2019jcyjmsxmX0725、0457) Open Fund of Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil&Gas Reservoirs in West China,Ministry of Education(KFJJ-XB-2020-4) the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN201901531). 

主　　题：tight gas sandbody scale effective sand reservoir Ordos Basin 

摘      要：Gas and water distribution is discontinuous in tight gas reservoirs,and a quantitative understanding of the factors controlling the scale and distribution of effective reservoirs is important for natural gas exploration.We used geological and geophysical explanation results,dynamic and static well test data,interference well test and static pressure test to calculate the distribution and characteristics of tight gas reservoirs in the H_(8) Member of the Shihezi Formation,Sulige gas field,Ordos Basin,northwest China.Our evaluation system examines the scale,physical properties,gas-bearing properties,and other reservoir features,and results in classification of effective reservoirs into types Ⅰ,Ⅱ,and Ⅲ that differ greatly in size,porosity,permeability,and saturation.The average thickness,length,and width of type Ⅰ effective reservoirs are 2.89,808,and 598 m,respectively,and the porosity is10.0%,permeability is10
10^(–3)µm^(2),and average gas saturation is60%.Compared with conventional gas reservoirs,tight gas effective reservoirs are small-scale and have low gas saturation.Our results show that the scale of the sedimentary system controls the size of the dominant microfacies in which tight gas effective reservoirs form.The presence of different types of interbeds hinders the connectivity of effective sand body reservoirs.The gas source conditions and pore characteristics of the reservoirs control sand body gas filling and reservoir formation.The physical properties and structural nature of the reservoirs control gas–water separation and the gas contents of effective reservoirs.The results are beneficial for the understanding of gas reservoir distribution in the whole Ordos Basin and other similar basins worldwide.