基于氮吸附和压汞数据确定致密储层孔径分布——以松辽盆地大安油田扶余油层为例

1)东北石油大学地球科学学院,黑龙江大庆 163318; 2)东北石油大学黑龙江省油气藏形成机理与 资源评价重点实验室,黑龙江大庆 163318; 3)大庆油田有限责任公司第三采油厂,黑龙江大庆 163113

储层评价; 氮吸附法; 压汞法; 先验概率; 致密储层; 有效整合; 孔径分布

Determination of pore-throat size distribution of tight reservoirs based on nitrogen adsorption and mercury injection data: an example from Fuyu oil layer in Daan oilfield of Songliao basin
ZHANG Yunfeng1,2, ZANG Qibiao1,2, SUN Bo1,2, JIANG Meiling1,2, WANG Mengmeng1,2, and YAN Ming3

1)College of Earth Sciences, Northeast Petroleum University, Daqing 163318, Heilongjiang Province, P.R.China2)Heilongjiang Oil and Gas Reservoir Forming Mechanism and Resource Evaluation Key Laboratory, Northeast Petroleum University, Daqing 163318, Heilongjiang Province, P.R.China3)No.3 Oil Production Plant of Daqing Oilfield Company Co. Ltd., Daqing 163113, Heilongjiang Province, P.R.China

reservoir evaluation; nitrogen adsorption method; mercury injection method; prior probability; tight reservoir; effective integration; pore-throat size distribution

DOI: 10.3724/SP.J.1249.2018.04353

备注

为实现对致密砂岩储层孔隙结构特征的整体分析,以松辽盆地大安油田扶余油层的致密砂岩样品为研究对象,利用先验概率比值合并的数学方法,将氮吸附和压汞法观察到的不同尺度的孔喉分布参数进行有效整合,实现从整体上对致密砂岩储层孔喉分布特征的准确把握,为客观合理进行致密储层综合研究与评价打下基础.研究结果表明,利用先验概率比值合并的数学方法,可有效地将氮吸附法和压汞法观察到的孔径范围进行整合; 氮吸附法仅能测得小于63 nm的孔喉,压汞法仅能测得大于6.3 nm的孔喉.根据整合分析结果,由样品的整体孔喉分布特征可知,S87号样品的孔喉主要分布在25~400 nm,S105号样品的孔喉主要分布在10~400 nm; 致密砂岩中,储层孔隙度相同时,渗透率越大,其大孔喉的含量越高.

In order to realize the analysis of pore structure characteristics of tight sandstone reservoir, by taking the sample of Fuyu tight sandstone reservoir in Daan oilfield of Songliao basin, the results of pore-throat distributions observed by nitrogen adsorption and mercury injection method are integrated by using the mathematical method of prior-probability ratio. The characteristics of pore-throat distribution of tight sandstone reservoir are obtained, which lays a foundation for the comprehensive study on the tight reservoirs. The results show that the pore-throat distributions observed by the method of nitrogen adsorption and the method of mercury injection can be effectively integrated by the method of prior-probability ratio; the nitrogen adsorption method can only measure the pore-throat smaller than 63 nm in diameter, and the method of mercury injection can only measure the pore-throat larger than 6.3 nm in diameter. The pore-throat diameter distribution of S87 sample is mainly in range of 25 nm and 400 nm, and that of S105 sample is mainly in range of 10 nm and 400 nm. In tight sandstone reservoirs, as the reservoir porosity is constant, the greater the permeability of reservoir, the higher the content of larger pore-throats.

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