摘要
为探究鄂尔多斯盆地陕北斜坡东南部地区致密砂岩储层的微观孔喉分布及其对含油性的影响,对长6—长8致密砂岩样品进行了场发射扫描电镜、高压压汞、核磁共振等测试,定量表征了其微观孔喉分布特征,分析了孔喉参数与含油性的关系。结果表明:研究区长6—长8致密砂岩储层孔隙类型主要为残余粒间孔、溶蚀孔、晶间孔;最小孔隙半径为0.5~6.3 nm,最大孔喉半径为1863.8~33859.7 nm;纳米孔、亚微米孔占总孔隙体积的61.2%~93.3%,微米孔占总孔隙体积的6.7%~38.8%,基本不发育毫米级孔隙。孔隙中的油水相分布峰值为50~100 nm。砂岩含油率与50 nm以上孔喉占比正相关,与亚微米孔占比正相关,与孔喉分选系数负相关。该研究成果对研究区致密砂岩含油性预测具有参考意义。
In order to explore the micro pore throat distribution and its influence on oil-bearing property of tight sandstone reservoirs in the southeast of Northern Shaanxi Slope in Ordos Basin,field emission scanning electron microscopy,high-pressure mercury injection and nuclear magnetic resonance(NMR)tests were carried out on Chang 6-Chang 8 tight sandstone samples to quantitatively characterize their micro pore throat distribution characteristics,and the relationship between pore throat parameters and oil-bearing property was analyzed.The results show that the pore types of Chang 6-Chang 8 tight sandstone reservoirs are mainly residual intergranular,dissolution pores and intercrystalline pores;the minimum pore radius is 0.5-6.3 nm;the maximum pore throat radius is 1,863.8-33,859.7 nm;the nano and submicron pores account for 61.2%-93.3%of the total pore volume,and the micro pores account for 6.7%-38.8%of the total pore volume,basically no millimetre pore is developed.The peak distribution range of oil and water phases in the pores is 50-100 nm.The oil content of sandstone is positively correlated with the proportion of pore and throat above 50nm,positively correlated with that of submicron pore,and negatively correlated with the sorting coefficient of pore throat.The conclusion has reference significance for oil-bearing property prediction of tight sandstone in study area.
作者
钟红利
吴雨风
张凤奇
屈伸
陈玲玲
ZHONG Hongli;WU Yufeng;ZHANG Fengqi;QU Shen;CHEN Lingling(Gollege of Geology&Environment,Xi′an University of Science and Technology,Xi′an 710054,China;School of Earth Science and Engineering,Xi′an Shiyou University,Xi′an 710065,China;Research Institute of Shaanxi Yanchang Petroleum(Group)Co.Ltd.,Xi′an 710075,China)
出处
《断块油气田》
CAS
CSCD
北大核心
2021年第1期21-27,共7页
Fault-Block Oil & Gas Field
基金
国家自然科学基金项目“致密砂岩储层微观孔喉非均质性及对石油分布的控制作用”(41502137)。
关键词
致密砂岩
长6—长8
孔喉分布
含油性
鄂尔多斯盆地
tight sandstone
Chang 6-Chang 8
pore throat distribution
oil-bearing property
Ordos Basin
