致密砂岩储层油气充注物性下限厘定:以鄂尔多斯盆地富县地区长8油藏为例  

Determination of Physical Properties Lower Limits of Oil-Gas Charging of Chang8 Tight Sandstone:Taking Chang8 Reservoir in Fuxian Area,Ordos Basin as an Example

作　　者：丁超 郭顺[3] 郭兰 王奇[4] DING Chao;GUO Shun;GUO Lan;WANG Qi(School of Earth Sciences and Engineering,Xi'an Shiyou University,Xi'an 710065,China;Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi'an Shiyou University,Xi'an 710065,China;Department of Resource Exploration and Development,Yanchang Oil(Group)Limited Liability Company,Xi'an 710075,China;Yanchang Oil Field Company,Yan'an 716000,China)

机构地区：[1]西安石油大学地球科学与工程学院,西安710065 [2]西安石油大学陕西省油气成藏地质学重点实验室,西安710065 [3]陕西延长石油(集团)有限责任公司资源与勘探开发部,西安710075 [4]延长油田股份有限公司,延安716000

出　　处：《科学技术与工程》2025年第2期484-493,共10页Science Technology and Engineering

基　　金：陕西省教育厅基金(20JS115);陕西省自然科学基础研究计划(2017JQ4013);西安石油大学博士科研启动基金(2014BS04)。

摘　　要：为了查明致密砂岩储层油气充注物性下限。通过大量岩心化验数据分析,明确长8储层类型、孔喉结构及物性情况。利用含油产状(试油)法、排驱压力法、统计学法、每米采油指数法、最小孔喉半径法等厘定有效储层现今物性下限,结合油气成藏时序与孔隙演定量化,反演油气充注期物性临界值。结果表明:富县地区长8储层类型以长石砂岩和岩屑长石砂岩为主,孔喉关系复杂,为低—特低孔、特低—超低渗致密储层;优选出现今长8有效储层临界下限值分别为7.0%和0.15 mD;反演Ⅰ期油气充注(距今192.5~152.0 Ma),物性下限值分别为20.8%和7.37 mD,Ⅱ期油气充注(距今152.0~126.0 Ma),物性下限值分别为8.2%和0.22 mD,Ⅲ期油气充注(距今65.0~36.5 Ma),为调整逸散,与现今物性下限基本一致。研究结果可为该区储层含油性评价与有利区预测提供地质依据。The physical properties lower limits of oil-gas charging in tight sandstone reservoirs are identified through a large number of core test and analysis data.The Chang8 reservoir types,pore-throat structure,and physical properties were clarified.Methods such as oil-gas occurrence,displacement pressure,physical property statistics,oil recovery index,and minimum pore-throat radius were employed to determine the current reservoir physical properties lower limit.By integrating the period of hydrocarbon accumulation and pore evolution,the critical physical properties during oil-gas charging were inverted.The results show that the reservoir types of Chang 8 are mainly feldspar sandstone and lithic feldspar sandstone in Fuxian area,with complex pore-throat relationship.These reservoirs are classified as tight reservoirs with low to extra-low porosity and extra-low to ultra-low permeability.It is preferred that the physical properties lower limits of the current reservoir are 7.0%and 0.15 mD,respectively.For inversion of oil-gas charging in Phase Ⅰ(192.5~152.0 Ma),the lower limits of physical properties are 20.8%and 7.37 mD,respectively,for oil-gas charging in Phase Ⅱ(152.0~126.0 Ma),the lower limits of physical properties are 8.2%and 0.22 mD.For oil-gas charging in Phase Ⅲ(65.0~36.5 Ma),the lower limits of physical properties are basically consistent with the current lower limits of physical properties.The research findings provide an significant geological basis for the evaluation of reservoir and the prediction of favorable in the study area.

关 键 词：致密储层 长8油藏 物性下限 油气充注 孔隙演化 

分 类 号：P618.13[天文地球—矿床学]