摘要
黔东南地区发育的新元古代下江群,与湖南中西部的板溪群,广西北部的丹洲群属于同期地层。本文根据下江群甲路组中所夹大理岩的地质特征及其碳氧同位素组成,认为其有可能与华北青白口系景儿峪组中上部对比。运用氧同位素地质温度计原理计算出该大理岩的变质温度在630℃左右,这个温度高于前人普遍认为下江群属于浅变质绿片岩相的温度,笔者认为这可能是甲路组层位较老,经历了较多变质作用的结果。下江群以大量的碎屑岩为主,仅局部层位,如甲路组中出现一些透镜状碳酸盐岩沉积,代表强烈的裂谷作用下出现短暂的相对稳定、浅海环境,并沉积碳酸盐岩。
In Southeast Guizhou deposition of Neoproterozoic Xiajiang Gr, the central and Western Hunan Banxi Gr, Northern Guangxi DanZhou Gr belongs to the strata of the corresponding period. According to the ic geothermomet-er principle applied to calculate the marble of the metamorphic temperature at around 630℃, the temperature higher than most previous researchers believed that Xiajiang Gr belongs to metamorphosed to greenschist facies of the temperature, the author think maybe it is a formation of the older, experienced as a result more metamorphism. Xiajiang Gr dominated by a large number of clastie rock, only local layers, such as Jialu Fm appear some lenticular carbonate sedimentary rocks, represent strong rifting appears short of relatively stable, shallow sea environment and carbonate sedimentary.
出处
《贵州地质》
2016年第2期91-95,107,共6页
Guizhou Geology
关键词
新元古代
甲路组
大理岩
碳氧同位素
沉积环境
The Neoproterozoic
Jialu Fm, marble
Carbon and oxygen isotope
Sedimentary environment
