首页|期刊导航|中国地球化学学报(英文版)|Sedimentary-volcanic tuffs formed during the early Middle Triassic volcanic event in Guizhou Province and their stratigraphic significance
中国地球化学学报(英文版)2005，Vol.24Issue(4)：338-344,7.
Sedimentary-volcanic tuffs formed during the early Middle Triassic volcanic event in Guizhou Province and their stratigraphic significance
Sedimentary-volcanic tuffs formed during the early Middle Triassic volcanic event in Guizhou Province and their stratigraphic significance
摘要
Abstract
The sedimentary-volcanic tuff (locally called "green-bean rock") formed during the early Middle Triassic volcanic event in Guizhou Province is characterized as being thin, stable, widespread, short in forming time and predominantly green in color. The green-bean rock is a perfect indicator for stratigraphic division. Its petrographic and geochemical features are unique, and it is composed mainly of glassy fragments and subordinately of crystal fragments and volcanic ash balls. Analysis of the major and trace elements and rare-earth elements (REE), as well as the related diagrams, permits us to believe that the green-bean rock is acidic volcanic material of the calc-alkaline series formed in the Indosinian orogenic belt on the Sino-Vietnam border, which was atmospherically transported to the tectonically stable areas and then deposited as sedimentary-volcanic rocks there. According to the age of green-bean rock, it is deduced that the boundary age of the Middle-Lower Triassic overlain by the sedimentary-volcanic tuff is about 247 Ma.关键词
volcanic event/boundary age/early Middle Triassic/GuizhouKey words
volcanic event/boundary age/early Middle Triassic/Guizhou分类
天文与地球科学引用本文复制引用
XIAO Jiafei ,HU Ruizhong..Sedimentary-volcanic tuffs formed during the early Middle Triassic volcanic event in Guizhou Province and their stratigraphic significance[J].中国地球化学学报(英文版),2005,24(4):338-344,7.基金项目
This work was supported by the Key Research Orientation Project under the Knowledge-innovation Program, Chinese Academy of Sciences (KZCX3-SW-125). （KZCX3-SW-125）
