摘要
本文通过测定杨木岗组变质凝灰岩中碎屑锆石U-Pb同位素年龄(291.9±2.6Ma),将其时代定为晚石炭纪。其岩石地球化学特征中微量元素B及其Sr/Ba比值显示了该组为陆相淡水(微咸水)沉积环境;稀土元素总量远低于地壳平均值,反映了该组形成于还原环境。轻稀土元素富,集,而重稀土元素亏损,说明该组形成处于酸性介质。
In this paper, the age of the zircon u-pb isotopic age (291.91.6ma) in the metamorphic tuff of yangmugang formation was determined as the late carboniferous period. The ratio of trace element B and Sr/Ba in the geochemical characteristics of rocks shows that the group is the sedimentary environment of terrestrial fresh water (brackish water). The total amount of rare earth elements is far below the average of the earth's crust, reflecting the formation of the group in the reduction environment. Light rare earth elements rich, set, and heavy rare earth elements loss, indicating that the group formed in the acid medium.
出处
《世界有色金属》
2017年第21期245-245,247,共2页
World Nonferrous Metals
基金
国家地质调查项目"黑龙江1/5万大贯屯等四幅区域地质矿产调查(1212011220475)"
关键词
杨木岗组
地球化学特征
晚石炭世
陆相还原环境
Yang muang group
geochemical characteristics
late carboniferous
land-phase reduction environment
