东北石油大学学报2024，Vol.48Issue(1)：1-12,12.DOI:10.3969/j.issn.2095-4107.2024.01.001
沉积环境对细粒沉积岩微观结构的影响
Effects of sedimentary environment on microstructures of fine-grained rocks:a case study of the Yanchang Formation 7 Member shale in the Ordos Basin as an example
摘要
Abstract
The microstructure characteristics of rocks are the internal basic properties of fine-grained rocks,which affect their physicochemical behavior.This paper takes an example as fine-grained grains in the Yanchang Formation 7 Member of Ordos Basin.First,the geometric morphology characteristics of fine-grained grains are analyzed quantitatively by field scanning electron microscope and image recog-nition technology.Then,we characterized the influence of the sedimentary environment on the geomet-ric shape and orientation arrangement of fine-grained grains.Results show that the grains in the deep-semi-deep lacustrine facies take the characteristics of fine grain size(2-3 μm),flat and angular shape.The grains are directionally distributed along with a continuous interval.The intensity of the distribu-tion shows a flat quasi-cone shape and well-directional orientation.The fine grains in shallow lake facies are medium-fine grains(2-8 μm),flat and angular type.Besides,the grains show a sharp distribution a-long with a certain interval with no obvious regularity,which has a moderate orientation arrangement.The fine grains in delta facies are fine-grained(8-12 μm)and quasi-circular type.This type of fine-grained rock has an irregular distribution.The intensity distribution of fine grains is circular or ellipti-cal.The circumferential angularity index and flatness of grains can promote the formation of oriented ar-rangement structure of grains.By contrast,the anisotropy rate and grain size are unfavorable for the formation of an oriented structure.The results are helpful to understand the microstructural characteris-tics of fine-grained rocks and establish the relationship between microstructures and macrostructures of rocks.关键词
细粒沉积岩/微观结构/几何特征/定向排列/扫描电镜/页岩/延长组7段/鄂尔多斯盆地Key words
fine-grained rock/microstructure/geometric features/orientation arrange/scanning elec-tron microscope/shale/Yanchang Formation 7 Member/Ordos Basin分类
能源科技引用本文复制引用
解馨慧,邓虎成,胡蓝霄,毛金昕,刘佳杰,夏宇,王园园,张鑫..沉积环境对细粒沉积岩微观结构的影响[J].东北石油大学学报,2024,48(1):1-12,12.基金项目
国家自然科学基金项目(42072182) （42072182）
