地球学报2017，Vol.38Issue(6)：872-882,11.DOI:10.3975/cagsb.2017.06.03
中国南方宝塔组灰岩的岩石学特征及其对"龟裂纹"成因的指示 ——以贵州桐梓县红花园乡宝塔组灰岩为例
Petrology of Limestone of Baota Formation in South China and Its Indication to the Genesis of "Turtle Crack": A Case Study of Baota Formation Limestone at Honghuayuan Township in Tongzi County, Guizhou Province
摘要
Abstract
The Baota limestone is widely distributed in the Yangtze area, and is characterized by unique "turtle crack" structure, which is a good marker for regional stratigraphic correlation. However, the relationship between the morphology of the "turtle crack" and the internal composition and structure of the rock remains unclear. Field outcrops and directional section observations indicate that Baota Formation limestone could be divided into two components, namely "grayish black reticulate patterns" and "grayish white matrix"; on the cut plane perpendicular to the strata, distal distribution of both components is in disorder, and the "V" shape arrangement is not obvious; cut plane which is parallel to the strata shares the same reticular morphology as weathering surface. Using cathodoluminescence, fluorescence, SEM, TOC and hardness testing, the authors carried out a series of comparative analyses on the petrological characteristics of "grayish black" reticulate patterns and "grayish white matrix". The results show that the former component is darker bioclastic limestone with lower hardness and higher content of organic matter, and asphalt veins can be seen under fluorescence; the latter component is lighter micrite with higher hardness and lower content of organic matter, and the fluorescence is not obvious. The difference in color and anti-weathering capability between two components is the internal cause for Baota Formation limestone forming "turtle crack" structure morphology on the ground.关键词
宝塔组/"龟裂纹"构造/组构差异性/抗风化能力Key words
Baota Formation/"turtle crack" structure/difference of components and structure/weathering resistance分类
天文与地球科学引用本文复制引用
禚喜准,陈骁帅,张林炎,崔建军,熊辉..中国南方宝塔组灰岩的岩石学特征及其对"龟裂纹"成因的指示 ——以贵州桐梓县红花园乡宝塔组灰岩为例[J].地球学报,2017,38(6):872-882,11.基金项目
本文由国家自然科学基金项目(编号: 41402101)和中国地质调查局地质调查项目"钦—杭结合带及临区深部地质调查"(编号: 121201104000160916)联合资助. This study was supported by National Natural Science Foundation of China (No. 41402101), and China Geological Survey (No. 121201104000160916). （编号: 41402101）
