不同变质类型煤的结构演化特征及其地质意义  

The structural evolution character of different types of coal metamorphism and its geological significance

作　　者：李小明[1,2] 曹代勇[2] 

机构地区：[1]华北科技学院安全工程中心,北京101601 [2]中国矿业大学地球科学与测绘工程学院,北京100083

出　　处：《中国矿业大学学报》2012年第1期74-81,共8页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(40872105);华北科技学院科研基金项目(A08002)

摘　　要：基于煤结构演化特征及其地质意义在煤化作用研究中的重要性,采用X射线衍射分析、电子顺磁共振分析、显微傅立叶变换红外分析、高分辨率透射电子显微镜研究了特殊环境下形成的不同变形-变质类型的构造煤.结果表明:3类不同变形-变质类型煤具有显著的系统差异:尤以区域变质煤与另两类区分显著,叠加在高温之上的构造应力能够促进碳原子面网间距(d002)减小、基本结构单元(BSU)的延展度(La)和堆砌度(Lc)增大、促使BSU向稚理化发展;该实验条件下,构造-热变煤的d002较另两类煤平均减小了0.012nm左右,而La和Lc平均值则分别为另两类煤的近2倍和3倍左右.构造应力不仅影响物理煤化作用,而且在一定程度上可以导致煤有机大分子化学结构和化学组成的改变,对煤结构的演化具有超前效应.Based on the importance of structural evolution character of coal and its geological significance in studying coalification, the deformed coals of different types of metamorphism under the special environment were investigated using X-ray diffraction, electron paramagnetic resonance, Fourier transformation infrared microspectroscopy and high-resolution transmission electron microscope. The results show that the three different types of coal metamorphism showed remarkable systemic differences, and the differences were obvious among the regional metamorphic coal and another two kinds. The superimposing tectonic stress due to high tem- perature of the environment resulted in the decrease of the lamellae spacing （d002） of the basic structural unit （BSU）, increase of the BSU diameter （La） and the BSU stack height （Lc） and the orientation increase of the BSU. Under the experimental conditions, the d002 of tectonic thermal metamorphic coal decreased 0. 012 nm compared to the other two types of coal. How- ever, the average values of La and Lc were nearly 2 times and 3 times to those of the other two types of coal, respectively. The tectonic stress not only affects physical coalification, but also leads to changes in chemical structures and compositions of organic micromolecules in coal, which suggests the leading effect to the structural evolution of coal.

关 键 词：煤 变质作用 结构演化 构造应力 地质意义 

分 类 号：P618.11[天文地球—矿床学]