Journal
GONDWANA RESEARCH
Volume 73, Issue -, Pages 175-189Publisher
ELSEVIER
DOI: 10.1016/j.gr.2019.03.018
Keywords
South China; Jiangnan Orogenic Belt; Neoproterozoic unconformity; Sibao Group; Detrital zircon geochronology
Categories
Funding
- National Fundamental Research Program of China (973 Program) [2012CB416701]
- National Natural Science Foundation of China [41772204, 41572200]
Ask authors/readers for more resources
The South China Block was built up by the assembly of the Yangtze and Cathaysia blocks along the Neoproterozoic Jiangnan Orogenic Belt. The timing of the Jiangnan Orogeny remains controversial. The widespread orogeny-related Neoproterozoic angular unconformity that separates the underlying folded Sibao (ca.1000-820 Ma) and overlying Danzhou (ca.800-720 Ma) Groups was investigated. Six sedimentary samples, below and above the unconformity in three distal localities (Fanjingshan. Madiyi, and Sibao) yield detrital zircon with U-Pb ages ranging from 779 +/- 16 Ma to 3006 +/- 36 Ma, with a prominent peak at ca. 852 Ma. The youngest ages of 832 +/- 11 Ma and 779 +/- 16 Ma arc revealed for the underlying Sibao and overlying Danzhou Groups, respectively. The detrital zircon U-Pb age relative probability plot of the Jiangnan Orogen matches well with those of the Yangtze and Cathaysia blocks since ca. 865 Ma. Integrating geological, geochemical and geochronological results, we suggest that the Paleo-South China Ocean began to subduct under the Yangtze block at ca. 1000 Ma, and was partly closed at ca. 865 Ma. Afterwards, the Yangtze and Cathaysia blocks initially collide at 865 Ma, forming the Jiangnan Orogen. This collision resulted in not only the folding of the Sibao Group, but also sediment deposition in a syn-collisional setting, which makes the upper part of the Sibao Group. The youngest S-type granite dated at ca. 820 Ma that intruded in the Sibao Group marks the late stage of the Jiangnan Orogeny. (C) 2019 Published by Elsevier B.V. on behalf of International Association for Gondwana Research.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available