Quantitative analysis of planation surfaces of the upper Yangtze River in the Sichuan-Yunnan Region, Southwest China
Quantitative analysis of planation surfaces of the upper Yangtze River in the Sichuan-Yunnan Region, Southwest China
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川滇地区长江上游夷平面定量分析
DOI：
10.1007/s11707-018-0707-y
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发表时间：
2018-06
影响因子：
2
通讯作者：
Huai Su
中科院分区：
文献类型：
--
作者：
Fenliang Liu;Hongshan Gao;Baotian Pan;Zongmeng Li;Huai Su
夷平面的识别是利用夷平面研究川滇地区长江上游地貌长期演化的关键。采用基于DEM的模糊逻辑与地形和河流剖面分析相结合的方法，综合分析坡度、曲率、地形粗糙度指数和相对高度4个地貌参数，建立相应的模糊隶属度函数，计算研究区的隶属度。结果表明，MD >80%、面积>0.4 km 2的斑块与Google Earth和野外调查结果吻合较好，代表PS残留。它们由1764个斑块组成，海拔高度、面积、平均坡度和起伏度分别为2000-2500 m、0-10 km ~ 2、4°-9°、0-500 m，占研究区景观的9.2%，从西北向东南倾斜，海拔高度逐渐降低。各斑块的海拔高度与坡度或起伏度之间没有明确的关系。这些结果表明，它们是受下地壳流动和上地壳断裂共同作用变形，并被长江上游水系切割的区域性连续PS的残留。此外，地形和河流剖面分析表明，三个PS（PS 1-PS 3）沿沿着主要山谷在永仁-会理地区发育良好，表明在晚新生代的几个阶段的隆升，然后夷平面。根据残留河流剖面在PS上的投影，结合侵蚀速率，估算出PS 1、PS 2和PS 3的破碎时间分别为3.47 Ma、2.19 Ma和1.45 Ma，表明现代长江上游河谷的出现始于上新世-早更新世。
Identification of the planation surfaces (PSs) is key for utilizing them as a reference in studying the long-term geomorphological evolution of the Upper Yangtze River Basin in the Sichuan-Yunnan region, Southwest China. Using a combined method of DEM-based fuzzy logic and topographic and river profiles analysis and based on a comprehensive analysis of four morphometric parameters: slope, curvature, terrain ruggedness index, and relative height, we established the relevant fuzzy membership functions, and then calculated the membership degree (MD) of the study area. Results show that patches with a MD >80% and an area >0.4 km2correspond well to the results of Google Earth and field investigation, representing the PS remnants. They consist of 1764 patches with an altitude, area, mean slope, and relief of mostly 2000–2500 m above sea level (asl), 0–10 km2, 4°–9°, 0–500 m, respectively, covering 9.2% of the study area’s landscape, dipping to southeast, decreasing progressively from northwest to southeast in altitude, and with no clear relation between each patch’s altitude and slope, or relief. All these results indicate that they are remnants of once regionally continuous PSs which were deformed by both the lower crust flow and the faults in upper crust, and dissected by the network of Upper Yangtze River. Additionally, topographic and river profiles analysis show that three PSs (PS1–PS3) well developed along the main valleys in the Yongren-Huili region, indicating several phases of uplift then planation during the Late Cenozoic era. Based on the incision amount deduced from projection of relict river profiles on PSs, together with erosion rates, breakup times of the PS1, PS2, and PS3 were estimated to be 3.47 Ma, 2.19 Ma, and 1.45 Ma, respectively, indicating appearance of modern Upper Yangtze River valley started between the Pliocene to early Pleistocene.
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影响因子：
1.8
作者：
Li Chaoyang;Jiang Xiaodian;Gong Wei;Li Deyong;Li Congying
通讯作者：
Li Congying
影响因子：
3.9
作者：
J. Bonow;P. Japsen;K. Lidmar-Bergström;J. Chalmers;A. Pedersen
通讯作者：
J. Bonow;P. Japsen;K. Lidmar-Bergström;J. Chalmers;A. Pedersen
影响因子：
3.9
作者：
M. Johansson
通讯作者：
M. Johansson
影响因子：
3.9
作者：
Jijun Li;Shi-you Xie;Mingsheng Kuang
通讯作者：
Jijun Li;Shi-you Xie;Mingsheng Kuang
影响因子：
3.3
作者：
Vicky L. Haider;J. Kropáček;I. Dunkl;B. Wagner;H. Eynatten
通讯作者：
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