Grenvillian orogeny in the Southern Cathaysia Block:Constraints from U-Pb ages and Lu-Hf isotopes in zircon from metamorphic basement

Metamorphic basement rocks in the Cathaysia Block are composed mainly of meta-sediments with different ages. New zircon U-Pb geochronological results from the meta-sedimentary rocks exposed in the Zengcheng and Hezi areas, southern Cathaysia Block, show that they consist dominantly of early Neoprote...

Full description

Bibliographic Details
Published in:Science Bulletin
Main Authors: Wang, LiJuan, Yu, JinHai, O'Reilly, S. Y., Griffin, W. L., Sun, Tao, Wei, ZhenYang, Jiang, ShaoYong, Shu, LiangShu
Format: Article in Journal/Newspaper
Language:English
Published: 2008
Subjects:
Online Access:https://researchers.mq.edu.au/en/publications/e9f6bd50-0798-45fa-af05-8ba20df6c564
https://doi.org/10.1007/s11434-008-0262-0
http://www.scopus.com/inward/record.url?scp=52949152391&partnerID=8YFLogxK
Description
Summary:Metamorphic basement rocks in the Cathaysia Block are composed mainly of meta-sediments with different ages. New zircon U-Pb geochronological results from the meta-sedimentary rocks exposed in the Zengcheng and Hezi areas, southern Cathaysia Block, show that they consist dominantly of early Neoproterozoic (1.0-0.9 Ga) materials with minor Paleo-to Mesoproterozoic and late Neoproterozoic (0.8-0.6 Ga) components, suggesting that the detritus mostly come from a Grenvillian orogen. The youngest detrital zircon ages place a constraint on the deposition time of these sediments in Late Neoproterozoic. Zircon Hf isotopic compositions indicate that the Grenvillian zircons were derived from the reworking of Mesoproterozoic arc magmatic rocks and Paleoproterozoic continental crust, implying an arc-continent collisional setting. Single-peak age spectra and the presence of abundant euhedral Grenvillian zircons suggest that the sedimentary provenance is not far away from the sample location. Thus, the Grenvillian orogen probably preexisted along the southern margin of the Cathaysia Block, or very close to the south. Similarity in the ages of Grenvillian orogeny and the influence of the assembly of Gondwana in South China with India and East Antarctic are discussed, with suggestion that South China was more likely linked with the India-East Antarctica continents in Early Neoproterozoic rather than between western Laurentia and eastern Australia.