四川盆地志留系龙马溪组泥页岩吸水模拟实验及对孔隙连通性的指示意义  

Experimental Investigation of Water Absorption and Its Significance on Pore Network Connectivity in Mudstone from Silurian Longmaxi Formation,Sichuan Basin

作　　者：吕海刚[1] 于萍[1] 闫建萍[1] 邵德勇 贾详娟 张同伟[1] 

机构地区：[1]兰州大学地质科学与矿产资源学院,甘肃省西部矿产资源重点实验室,甘肃兰州730000

出　　处：《天然气地球科学》2015年第8期1556-1562,共7页Natural Gas Geoscience

基　　金：国家重点基础研究发展规划(“973”)项目(编号:2012CB214701);中央高校基本科研业务费专项基金(编号:lzujbky-2013-114);国家自然科学基金(编号:41202095);教育部科学技术研究重大项目(编号:311010)联合资助

摘　　要：采用岩石小柱体吸水实验方法,结合N2吸附法对孔隙结构和BET比表面积的测量,以及TOC含量和黏土矿物含量的分析,研究了龙马溪组富有机质泥页岩对水的吸收程度,以此来探讨影响泥岩吸水的主控因素,以及对孔隙连通性的指示意义。结果表明:TOC和黏土矿物是影响泥页岩吸水的主控因素,泥岩吸水量与BET比表面积具较好的正相关性,吸水过程自发且可逆。相同泥页岩样品的绝对吸水量与其体积变化呈直线关系,斜率为单位体积吸水量,可计算泥岩有效孔隙度(6.23%),吸水研究为泥岩中孔隙的连通性和有效孔隙度的测量提供了新的手段。The water uptake and main controlling factors on the organic-rich mudstone of Longmaxi Formation are investigated by water absorption experiment,N2 absorption and TOCand clay mineral contents.The results show that TOCand clay mineral contents are key factors that affect water absorption on mudstone.Water uptake in mudstone has a positive correlation with BET surface area,and the water uptaking in mudstone absorption is spontaneous and reversible.Based on the linear correlation between saturated water uptake of the same sample with different sample size and volume,the calculated effective porosity is6.23%.Water absorption experiment provides a new method to measure the connected and effective porosity.

关 键 词：泥页岩 孔隙特征 连通性 吸水模拟 

分 类 号：TE122.2[石油与天然气工程—油气勘探]