地质通报2018，Vol.37Issue(4)：682-692,11.
甘肃多坝沟地区黑云斜长片麻岩锆石U-Pb年龄和Hf同位素特征
Zircon U-Pb age and Hf isotopes of the biotite plagioclase genesis in Duobagou area,Gansu Province
摘要
Abstract
The LA-ICP-MS zircon U-Pb age and zircon Lu-Hf isotope were analyzed for biotite-plagioclase gneiss from Duoba-gou area,Dunhuang terrain,with the purpose of determining the formation age of the Dunhuang complex and discussing the crustal growth and evolution history of the Dunhuang terrain during Precambrian. Zircon U-Pb dating results indicate that the maximum depositional age of supracrustal rocks from the Dunhuang complex is ca.710Ma.Additionally,the studied biotite-plagioclase gneiss indicates a metamorphic event at 422Ma,suggesting that the Precambrian Dunhuang terrain might have been involved in the subduc-tion-collision process of the Paleo-Asian Ocean during Early Paleozoic.Zircon Hf isotopes show that the Dunhuang terrain experi-enced episodic crustal growth events at ca.2.7Ga,ca.2.5Ga,ca.2.3Ga,ca.2.0Ga and ca.1.8Ga,suggesting episodic crustal growth.It is considered that the tectonic attribute could be compared with that of the Tarim craton during Neoproterozoic, as shown by the peak age at ca.0.9Ga and ca.0.8Ga.关键词
多坝沟/敦煌杂岩/碎屑锆石U-Pb年龄/锆石Lu-Hf同位素Key words
Duobagou area/Dunhuang complex/detrital zircon U-Pb age/zircon Lu-Hf isotope分类
天文与地球科学引用本文复制引用
朱涛,王洪亮,徐学义,赵燕,李智佩,朱小辉..甘肃多坝沟地区黑云斜长片麻岩锆石U-Pb年龄和Hf同位素特征[J].地质通报,2018,37(4):682-692,11.基金项目
国家自然科学基金项目《敦煌地区高镁闪长岩成因与深部地球动力学过程研究》(批准号:41702235)、中国地质调查局项目《西北基础地质综合调查与片区总结》(编号:1212011220649)和《祁连成矿带肃南—大柴旦地区地质矿产调查》(编号:DD20160012) （批准号:41702235）
