摘要
为表征青藏高原东北部地区泥岩的微结构特征,应用扫描电镜(SEM)对泥岩微结构空间特征(基本单元体特征、排列特征、连结特征)进行了观测。利用Image Pro Pluss(IPP)软件对孔隙结构(孔径、分形维数、面孔率、圆度)进行了定量化分析。结果表明:①研究区泥岩微结构类型以平片、密集(开放)、面-面(边-边)连结为主;②研究区泥岩主要发育微孔和中孔,孔隙的分形维数、面孔率、圆度、平均直径的变化范围分别是1.0810∼1.1700、0.62%∼4.25%、1.4519∼2.5047、7.5327∼22.4523μm;③不同地质时代的泥岩面孔率、孔径分布、孔隙数量均存在较大差异;④同一地质时代,面孔率、分维数、圆度、平均直径均有随埋置深度的增加而增大的趋势。青藏高原东北部西宁地区泥岩的微观结构是其产生膨胀的主要因素,对于该地区泥岩的膨胀工程特性研究具有重要的参考价值。
In order to study the microstructure characteristics of mudstones collected from Xining area, a study site located in the Northeastern Qinghai Tibet Plateau, in this paper, Scanning Electron Microscope (SEM) was used to study the spatial characteristics of microstructure of mudstone, including basic unit features, arrangement features, and connection characteristics, and Image Pro Plus (IPP) was used to reveal the pore structure of mudstone, including mean diameter, fractal dimension, face rate, and roundness. The results are as follows;① the micro-structure types of mudstone collected from this study area was found to be mainly flat, intensive (open), and face-to-face (edge-edge) connections;② its main types of pored structure was found to be the inter granular pores, and micropores and mesopores were found to be the main types of pore structure based on their diameters. The variation range of fractal dimension, mean diameter, roundness, and plane porosity were found to be 1.0810 1.1700, 7.5327μm 22.4523μm, 1.4519 2.5047, and 0.62% 4.25%, respectively;③ for different geological ages, plane porosity, distribution, and number of pores of the studied mudstone show huge difference;④ for the same geological age, plane porosity, fractal dimension, roundness, and mean diameter of the studied mudstone were found to be increased with increasing depth. The microstructure of mudstone in the northeastern Tibetan Plateau is the main factor for expansion, and it has important reference value for the study on the expansion engineering property of mudstone in this area.
作者
关欢
任勇
孙春卫
巫锡勇
GUAN Huan;REN Yong;SUN Chunwei;WU Xiyong(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Earth Sciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China)
出处
《高原科学研究》
CSCD
2019年第4期47-57,共11页
Plateau Science Research
基金
国家自然科学基金（41877215)
