The evolution of eastern Sichuan basin, Yangtze block since Cretaceous: constraints from low temperature thermochronology
In Yangtze block (South China), there is a well-developed Mesozoic thrust system extended through the Xuefeng and Wuling mountains in the southeast to the Sichuan basin in the northwest. We present 11 apatite fission-track (AFT) data and 11 (U-Th-Sm)/He ages to unravel the low temperature thermal hi...
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| Main Authors: | , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2016
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| In: |
Journal of Asian earth sciences
Year: 2015, Volume: 116, Pages: 208-221 |
| ISSN: | 1878-5786 |
| DOI: | 10.1016/j.jseaes.2015.11.008 |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1016/j.jseaes.2015.11.008 Verlag, lizenzpflichtig, Volltext: http://www.sciencedirect.com/science/article/pii/S1367912015301371 
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| Author Notes: | Hongcai Shi, Xiaobin Shi, Ulrich A. Glasmacher, Xiaoqiu Yang, Daniel F. Stockli |
| Summary: | In Yangtze block (South China), there is a well-developed Mesozoic thrust system extended through the Xuefeng and Wuling mountains in the southeast to the Sichuan basin in the northwest. We present 11 apatite fission-track (AFT) data and 11 (U-Th-Sm)/He ages to unravel the low temperature thermal history of a part of the system located in the eastern Sichuan basin. The fission-track data are interpreted using a grain-age deconvolution algorithm with inverse thermal modeling of track length, grain ages and mineral composition proxy data. Results suggest that apatite fission-track ages range between 99.3±8.1 and 51.0±4.0Ma, and the apatite (U-Th-Sm)/He ages between 58.3±3.5Ma and 14.2±0.9. The spatial distribution of these ages shows a trend decreased from SE to NW gradually, which supports the idea of a prolonged, steady-state rock uplift and erosion process across the eastern Sichuan basin. Thermal history modeling of the combined FT and (U-Th-Sm)/He datasets reveal a common three stage cooling history: (1) initial stage of rapid cooling that younger to the east during pre-Cretaceous, (2) following by a period of relative (but not perfect) thermal stability at ∼65-50°C, (3) and then a new rapid cooling stage that initiated in all samples between ∼15 and 20Ma. The first rapid cooling at a rate of ⩾1.5°C/Ma is associated with coeval tectonism in nearby regions, which result in folds and faults of the eastern Sichuan basin. Early-mid Cenozoic thermal stability is contributed to the extension widely occurring in the eastern China continent at which the average cooling rate decreased to ∼0.16°C/Ma. Causes for speculative accelerated cooling after ca. 20-15Ma with a rate of ⩾1.2°C/Ma may be a far-field effect of upward and eastward growth of the Tibetan Plateau but could also be related to climate effects. In a whole, this paper analyzes the several Mesozoic and Cenozoic tectonic events influence to the patters of regional denudation. |
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| Item Description: | Available online 14 November 2015 Gesehen am 06.05.2020 |
| Physical Description: | Online Resource |
| ISSN: | 1878-5786 |
| DOI: | 10.1016/j.jseaes.2015.11.008 |