干旱区生态环境知识资源中心(Arid): Gradients in climate, geology, and topography affecting coastal alluvial fan morphodynamics in hyperarid regions

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DOI	10.1016/j.gloplacha.2019.102994
	Gradients in climate, geology, and topography affecting coastal alluvial fan morphodynamics in hyperarid regions - The Atacama perspective
	Walk, Janek 1; Stauch, Georg 1; Reyers, Mark 2; Vasquez, Paulina 3; Sepulveda, Fernando A.3; Bartz, Melanie 4; Hoffmeister, Dirk 4; Brueckner, Helmut 4; Lehmkuhl, Frank 1
通讯作者	Walk, Janek
来源期刊	GLOBAL AND PLANETARY CHANGE
ISSN	0921-8181
EISSN	1872-6364
出版年	2020
卷号	185
英文摘要	Along the coast of the hyperarid Atacama Desert, late Quaternary alluvial fans emerge from the Coastal Cordillera to the Pacific Ocean between 20.5 degrees S and 25.5 degrees S. Coastal alluvial fans (CAF) show, in comparison to the interior fans of the Atacama Desert, pronounced recent activity. However, the complex interplay between climate, lithology, and tectonics affecting the CAF morphodynamics in such hyperarid coastal settings needs to be better understood. We therefore aim at assessing the major factors driving CAF activity and evaluate their effects along gradients. We conducted an extensive study relating climatic, lithologic, and tectonic characteristics to fan and catchment geomorphology of 123 CAF. Geomorphometric analyses are based on the 12.5 m TanDEM-X WorldDEM (TM), catchment lithology and faults are extracted from 13 regional geological maps, and the frequency of heavy rainfall events capable of activating CAF is derived from a Weather Research and Forecasting (WRF) regional climate model. Our results point to a primary climatic control on CAF morphodynamics shown in functional relationships with catchment hydromorphometric characteristics reflecting a high susceptibility to debris flows - the main CAF-constructing process. Catchment properties along the latitudinal gradient reflect the source of significant precipitation events: frontal systems and cut-off lows which mainly originate in the extratropics and become increasingly rare towards the north. The frequency of precipitation extremes can only be correlated to the hydromorphometry and geomorphic maturity of catchments that feature a high degree of sediment transport potential and generally do not cut back far into the Coastal Cordillera. Related to the strongly reduced influence of the Pacific precipitation source towards the east, this additional climatic transition is governed by the orographic effect of the steep W-E gradient in topography. In contrast, source-area lithology is of negligible relevance for CAF catchment morphometry and fan activity. An important indirect influence of tectonics, however, can be seen in the long-term (neo)tectonic activity within the Coastal Cordillera, which in turn shapes catchments and controls the topography.
英文关键词	Alluvial fan Coast Atacama Desert Geomorphometry TanDEM-X WRF model
类型	Article
语种	英语
国家	Germany ; Chile
收录类别	SCI-E
WOS记录号	WOS:000510315900017
WOS关键词	NORTHERN CHILE ; DEBRIS-FLOW ; EL-NINO ; SEDIMENT CONNECTIVITY ; SOUTH-AMERICA ; MAGMATIC ARC ; FORE-ARC ; TARAPACA REGION ; MARINE TERRACES ; MIOCENE AGE
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS研究方向	Physical Geography ; Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/314621
作者单位	1.Rhein Westfal TH Aachen, Dept Geog, D-52056 Aachen, Germany; 2.Univ Cologne, Inst Geophys & Meteorol, D-50923 Cologne, Germany; 3.Serv Nacl Geol & Mineria, Santiago 0104, Chile; 4.Univ Cologne, Inst Geog, D-50674 Cologne, Germany
推荐引用方式 GB/T 7714	Walk, Janek,Stauch, Georg,Reyers, Mark,et al. Gradients in climate, geology, and topography affecting coastal alluvial fan morphodynamics in hyperarid regions - The Atacama perspective[J],2020,185.
APA	Walk, Janek.,Stauch, Georg.,Reyers, Mark.,Vasquez, Paulina.,Sepulveda, Fernando A..,...&Lehmkuhl, Frank.(2020).Gradients in climate, geology, and topography affecting coastal alluvial fan morphodynamics in hyperarid regions - The Atacama perspective.GLOBAL AND PLANETARY CHANGE,185.
MLA	Walk, Janek,et al."Gradients in climate, geology, and topography affecting coastal alluvial fan morphodynamics in hyperarid regions - The Atacama perspective".GLOBAL AND PLANETARY CHANGE 185(2020).