天然气勘探与开发2024，Vol.47Issue(3)：85-93,9.DOI:10.12055/gaskk.issn.1673-3177.2024.03.010
致密砂岩压裂后的储层敏感性特征实验
Experimental study on reservoir sensitivity characteristics of tight sandstone after fracturing:Taking No.8 sand body of Shaximiao Formation in JQ area of Sichuan Basin as an example
汪煜昆 1赵丹 2刘婷芝 2淦文杰 1王永强 1张清秀 2郭静姝2
作者信息
- 1. 中国石油西南油气田公司川中油气矿 四川遂宁 629000
- 2. 中国石油西南油气田公司勘探开发研究院 四川成都 610041
- 折叠
摘要
Abstract
With the expansion of hydrocarbon exploration into unconventional fields,the reservoir stimulation treatments such as fracturing are increasingly applied.For purposes of understanding reservoir properties,figuring out reservoir potential,predicting the changes in reser-voir sensitivity characteristics after stimulation,and then implementing appropriate reservoir protection,it is necessary to conduct sensitivity experiments on reservoir cores after simulated stimulation in order to identify how the stimulation affects the reservoir sensitivity character-istics.Through thin section identification,X-ray diffraction,scanning electron microscopy,and mercury injection test,flow experiments were carried out for drilled cores under different pressures,temperatures and fluid chemical properties to evaluate the reservoir sensitivity char-acteristics.The results of sensitivity experiments on cores before and after stimulation were compared to analyze the impacts of stimulation treatment on reservoir sensitivity characteristics.The results are shown as follows:(ⅰ)There appears netlike fractures in the cores drilled from No.8 sand body of the Middle Jurassic Shaximiao Formation in the JQ area of Sichuan Basin after stimulation,and the core permeability is 167%higher averagely than that before stimulation.(ⅱ)The cores are characterized by moderate to weak velocity sensitivity,strong water sensitivity,weak salt sensitivity,weak alkali sensitivity,and weak acid sensitivity.After stimulation,the characteristics of velocity sensitivity and salt sensitivity remain unchanged,while the strong water sensitivity changes to a weak level.Moreover,the proportion of core samples with strong water sensitivity reduces to 17%from 93%.(ⅲ)Comprehensive analysis indicates that the stimulated cores present a reduced level of water sensitivity,which manifests as weak or zero water sensitivity.Thus,the coverage of reservoir stimulation treatments needs to be expanded so as to improve the reservoir fluid flow capacity.关键词
致密砂岩/渗流实验/储层改造/敏感性特征/CT扫描Key words
Tight sandstone/Seepage experiment/Reservoir stimulation/Sensitivity characteristics/CT scanning引用本文复制引用
汪煜昆,赵丹,刘婷芝,淦文杰,王永强,张清秀,郭静姝..致密砂岩压裂后的储层敏感性特征实验[J].天然气勘探与开发,2024,47(3):85-93,9.
