摘要
为了研究页岩拉张型微裂缝中的渗流规律，采用巴西实验在5块Barnett页岩岩心中形成拉张型裂缝。采用三维面轮廓仪获取裂缝面形态，基于扫描原理将三维信息转换为二维信息计算迂曲度、倾角、粗糙度等特征参数，引入聚类分析方法明确各参数间距离，采用格子玻尔兹曼方法模拟开度在0．05～0．40mm范围内页岩微裂缝渗流，并结合理论分析推导微裂缝渗透率计算公式。结果表明：所选取样本迂曲度在1．10左右，倾角为0．99°～8．86°，粗糙度为0．062-0．162mm；迂曲度、粗糙度、倾角对渗透率影响不存在替代关系，必须同时考虑三者的影响；计算微裂缝渗透率比平板模型渗透率要小19％-29％，说明必须考虑裂缝粗糙度影响；经验证，推导的渗透率计算公式误差控制在4％以内，可用于拉张型微裂缝渗透率计算。
To study fluid flow in shale tensile micro-fractures, five shale core samples, taken from Barnnet Shale, were splitted into artificial tensile fractures based on Brazilian test. The morphology of the artificial fractures was obtained by a 3-D laser sensor profilometer. Then, 3-D information was transformed into 2-D information and the quantitative parameters, such as tortuosity, surface angularity and roughness, were calculated based on the scanning principle. Cluster analysis was introduced to make sure the distance among the parameters, the fluid flow in shale micro-fractures with the opening of 0.05-0.40 mm was simulated by Lattice Boltzmann Method （LBM）, and an equation was derived for calculating the shale tensile micro-fracture permeability. The results show that, the tortuosity of the samples is close to 1.10, the angularity is among 0.99°-8.86°, and the roughness is among 0.062-0.162 mm; the parameters cannot be substituted by one another and their effects should be considered at the same time; the micro-fracture permeability is less 19%-29% than the parallel plate model permeability, so the roughness should be included. It is verified that the deviation of the equation is less than 4%, and it can be used to calculate shale tensile micro-fracture permeability.
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2016年第1期115-120,152,共7页
Petroleum Exploration and Development
基金
国家科技重大专项“大型油气田及煤层气开发”(2011ZX05051)
国家自然科学基金(51404288)
作者简介
曲冠政（1986-），男，山东莱州人，中国石油大学（华东）石油工程学院在读博士研究生，从事裂缝结构及渗流特征方面的研究工作。地址：山东省青岛市经济技术开发区，中国石油大学（华东）石油工程学院，邮政编码：266555。E-mail：quguanzheng@126．com
