摘要
康布铁堡组的变质程度为绿片岩—低角闪岩相 ,已报道的同位素年龄均为变质年龄。根据锆石颜色、晶形、U Pb同位素组成 ,将该组酸性火山岩中的锆石分为继承性锆石、岩浆锆石、混合锆石 (含继承锆石核 )和变生锆石 4类。通过单颗粒锆石U Pb法年龄测定 ,获得了康布铁堡组火山岩的年龄 (4 0 7.3± 9.2 )Ma ,属早泥盆世 ,同时得出两期变质年龄和火山岩源区的参考年龄。
The rocks of the Kangbutiebao Formation suffered greenschist low amphibolite facies metamorphism. The isotope ages reported are all metamorphic ones. According to the colors, crystal shapes and U Pb isotopic composition of zircons, the zircons in acid volcanic rocks of the formation may be divided into inherited zircon, magmatic zircon, mixed zircon (containing a small core of inherited zircon) and metamorphic zircon. The volcanic rocks of the formation were determined using the single grain zircon U Pb method to have an age of 407.3±9.2 Ma, assigned to the Early Devonian age. Meanwhile the ages of two phases of metamorphism and reference age of the source region of volcanic rocks have been obtained.
出处
《中国区域地质》
CSCD
2000年第3期281-287,共7页
Regional Geology of China
基金
国家"九五"科技项目!<可可塔勒多金属成矿带隐伏矿定位预测研究>(96 - 915 - 0 2 - 0 3)
关键词
康布铁堡组
锆石
新疆阿尔泰
造山带
变质火山岩
Kangbutiebao Formation
metarhyolite
zircon characteristics
U Pb age
Altay
