摘要
本文首次报道了扬子地台北部湖北宜昌地区崆岭群和陕西碑坝地区后河组中存在大量TTG片麻岩。崆岭群TTG片麻岩主要由英云闪长片麻岩组成,U-Pb锆石年龄为2850±15Ma,崆岭群岩石建造特征类似于太古宙高级区,后河组TTG片麻岩主要由英云闪长和奥长花岗片麻岩组成。两套TTG片麻岩的地球化学特征与太古宙TTG片麻岩一致,它们的发现为扬子地台存在太古宙陆壳提供了直接的物质证据。
This paper reports, for the first time, the presence of voluminous TTG gne-iss in two areas of the northern Yangtze Platform. The Kongling TTG gneiss in the Yichang area, Hubei Province is dominated by tonalitic gneiss with the U-Pb zircon age of 2850±15 Ma and shows, together with its overlying supracrustals, resemblance in rock association to Archean high-grade terrains. The Houhe TTG gneiss in the Beiba area, Shaanxi Province consists of tonalitic and trondhjemitic gneiss. These two suites of TTG gneisses have geochemical characteristics similar to those of the Archean TTG gneiss and their discovery provides the direct evi-dence for the presence of Archean continental crust in the Yangtze Platform.
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
1990年第6期675-679,共5页
Earth Science-Journal of China University of Geosciences
关键词
片麻岩
太古宙
扬子地台
后河组
Yangtze Platform, TTG gneiss,Archean continental crust, Kong-ling Group,Houhe Formation.
