Alluvial terrace systems in Zhangjiajie of northwest Hunan, China: Implications for climatic change, tectonic uplift and geomorphic evolution

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• 作者：Guifang Yang^a ; ^{yangguifang@cugb.edu.cn} ; Xujiao Zhang^a ; Mingzhong Tian^a ; Gary Brierley^b ; Anze Chen^c ; Yamin Ping^a ; Zhiliang Ge^a ; Zhiyun Ni^a ; Zhen Yang^a
• 刊名：Quaternary International
• 出版年：2011
• 出版时间：1 March 2011
• 年：2011
• 卷：233
• 期：1
• 页码：27-39
• 全文大小：3463 K

文摘

This paper reports the latest details from two comprehensive investigations of alluvial terrace sequences in Zhangjiajie, northwest Hunan Province, China. Seven alluvial terrace units along the Maoxi River and four terrace sequences along the Suoxi River record significant regional geomorphic history. Rates of regional Quaternary uplift and climate change are reconstructed using topographic and stratigraphic evidence from terrace and adjacent cave deposits, along with Electron Spin Resonance (ESR) and Thermo-luminescence (TL) dating controls. Between 928 ka and 689 ka the time-averaged uplift rate (or incision rate) was 0.16 m/ka. The rate decreased to 0.05 m/ka between 689 ka and 347 ka, and then increased slightly to 0.11–0.14 m/ka after 347 ka. The inferred incision rate increased roughly from 0.21–0.32 m/ka to 0.51 m/ka from the Late Pleistocene to present. The seven alluvial phases (T₇ − T₁) and their associated chronology are consistent with climatic variations at regional and/or global scales, suggesting that these terraces represent climate-driven pauses imprinted atop the record of long-term tectonically induced incision by rivers. Insights from these alluvial terrace staircases and cave features indicate that the spectacular sandstone peak forest landscape of the study area has emerged since the middle period of the Middle Pleistocene.