Detrital Zircon U–Pb Geochronology and Provenance of Bayan Obo Group, Northern Margin of North China Craton: New Implications for the Position of NCC in Rodinia

论文摘要

The paleoposition of North China Craton in Rodinia has long been in controversial. This paper mainly focuses on the U–Pb geochronological studies of detrital zircons obtained from Bayan Obo Group exposed in the Shangdu area, Inner Mongolia, aiming to provide more information for interprating this problem. Based on the acquired data, this paper comes to the following conclusions. Firstly, the depositional age of Bayan Obo Group might be from Meso– to Neoproterozoic according to the zircons U–Pb dating results. The lower succession of this group, namely Dulahala and Jianshan formations deposited between 1800 and 1650 Ma. The Halahuogete and Bilute formations deposited between 1500 and 1350 Ma. For Baiyinbaolage and Hujiertu formations, their depositional age was 1250–900 Ma. Secondly, for the provenance of Bayan Obo Group, this paper believes detrital zircons with age of 2.51–2.71 Ga and 2.00–2.48 Ga were from Guyang, Xi Ulanbulang and Zhuozi area; the Khondalite Belt provided detrital zircons with age of 1.95–1.80 Ga; zircons with age of 1.60–1.75 Ga might come from granitic rocks in Miyun Area. The magmatism after 1.60 Ga was rarely recorded in the NCC, therefore those zircons with ages younger than 1.60 Ga might come from outside of NCC. The magmatism with the same age existed in Baltic, Amazonia and Laurentia. Based on previous paleomagnetic researches, this paper proposes that NCC might receive detritus from Baltic during 1560–1350 Ma and had affinity with Laurentia and Amazonia at ～0.9 Ga in Rodinia. Baltic, Amazonia and Laurentia might be potential provenances for non–NCC detritus in Bayan Obo Group.

论文目录

• 1 Introduction
• 2 Geological Background
• 3 Samples and Methods
•   3.1 Sample descriptions
•   3.2 Methods
• 4 Results
• 5 Discussions
•   5.1 Depositional age of Bayan Obo Group
•   5.2 NCC provenance
•   5.3 Non–NCC provenance
• 6 Conclusions

文章来源

类型: 期刊论文

作者: LI Changhai,LIU Zhenghong,XU Zhongyuan,DONG Xiaojie,LI Pengchuan,SHI Qiang,WANG Shijie

来源: Acta Geologica Sinica(English Edition) 2019年05期

年度: 2019

分类: 基础科学

专业: 地质学

单位: College of Earth Sciences, Jilin University,Key Laboratory of Mineral Resources Evaluation in Northeast Asia, Ministry of Natural Resources

基金: financially supported by the National Natural Science Foundation of China (No.41872203),China Geological Survey (No.1212011120709),Doctoral Candidate Inter Discipline Fund of Jilin University (No.10183201837)

分类号: P597.3

页码: 1397-1416

总页数: 20

文件大小: 1277K

下载量: 14