干旱区生态环境知识资源中心(Arid): INVERTED CHANNEL VARIATIONS IDENTIFIED ON A DISTAL PORTION OF A BAJADA IN THE CENTRAL ATACAMA DESERT, CHILE

Arid

DOI	10.1016/j.geomorph.2021.107925
	INVERTED CHANNEL VARIATIONS IDENTIFIED ON A DISTAL PORTION OF A BAJADA IN THE CENTRAL ATACAMA DESERT, CHILE
	Williams, Rebecca M. E.; Irwin, Rossman P., III; Dobrea, Eldar Z. Noe; Howard, Alan D.; Dietrich, William E.; Cawley, J. C.
通讯作者	Williams, RME (corresponding author), Planetary Sci Inst, 1700 Ft Lowell,Suite 106, Tucson, AZ 85719 USA.
来源期刊	GEOMORPHOLOGY
ISSN	0169-555X
EISSN	1872-695X
出版年	2021
卷号	393
英文摘要	In deserts, the interplay between occasional fluvial events and persistent aeolian erosion can form composite modern and relict surfaces, especially on the distal portion of alluvial fans. There, relief inversion of alluvial deposits by differential erosion can form longitudinal ridges. We identified two distinct ridge types formed by relief inversion on converging alluvial fans in the hyperarid Chilean Atacama Desert. Although they are co-located and similar in scale, the ridge types have different ages and formation histories that apparently correspond to minor paleoclimate variations. Gravel-armored ridges are remnants of deflated alluvial deposits with a bimodal sediment distribution (gravel and sand) dated to a minor pluvial phase at the end of the Late Pleistocene (similar to 12 kyr). In contrast, younger (similar to 9 kyr) sulfate-capped ridges formed during a minor arid phase with evaporite deposition in a pre-existing channel that armored the underlying deposits. Collectively, inverted channels at Salar de Llamara resulted from multiple episodes of surface overland flow and standing water spanning several thousand years. Based on ridge relief and age, the minimum long-term deflation rate is 0.1-0.2 m/kyr, driven primarily by wind erosion. This case study is an example of the equifinality concept whereby different processes lead to similar landforms. The complex history of the two ridge types can only be generally constrained in remotely sensed data. In situ observations are required to discern the specifics of the aqueous history, including the flow type, magnitude, sequence, and paleoenvironment. These findings have relevance for interpreting similar landforms on Mars.
类型	Article
语种	英语
开放获取类型	hybrid
收录类别	SCI-E
WOS记录号	WOS:000702871000005
WOS关键词	PAMPA DEL TAMARUGAL ; NORTHERN CHILE ; ALLUVIAL-FAN ; HYPERARID CORE ; GROUNDWATER RECHARGE ; CLIMATE-CHANGE ; GYPSUM CRUSTS ; AEOLIS DORSA ; MIOCENE AGE ; GALE CRATER
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS研究方向	Physical Geography ; Geology
来源机构	University of California, Berkeley
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/363427
作者单位	[Williams, Rebecca M. E.; Dobrea, Eldar Z. Noe; Howard, Alan D.] Planetary Sci Inst, 1700 Ft Lowell,Suite 106, Tucson, AZ 85719 USA; [Irwin, Rossman P., III; Cawley, J. C.] Smithsonian Inst, Ctr Earth & Planetary Studies, Natl Air & Space Museum, POB 37012,MRC 315, Washington, DC 20013 USA; [Dietrich, William E.] Univ Calif Berkeley, Earth & Planetary Sci, 307 McCone Hall, Berkeley, CA 94720 USA
推荐引用方式 GB/T 7714	Williams, Rebecca M. E.,Irwin, Rossman P., III,Dobrea, Eldar Z. Noe,et al. INVERTED CHANNEL VARIATIONS IDENTIFIED ON A DISTAL PORTION OF A BAJADA IN THE CENTRAL ATACAMA DESERT, CHILE[J]. University of California, Berkeley,2021,393.
APA	Williams, Rebecca M. E.,Irwin, Rossman P., III,Dobrea, Eldar Z. Noe,Howard, Alan D.,Dietrich, William E.,&Cawley, J. C..(2021).INVERTED CHANNEL VARIATIONS IDENTIFIED ON A DISTAL PORTION OF A BAJADA IN THE CENTRAL ATACAMA DESERT, CHILE.GEOMORPHOLOGY,393.
MLA	Williams, Rebecca M. E.,et al."INVERTED CHANNEL VARIATIONS IDENTIFIED ON A DISTAL PORTION OF A BAJADA IN THE CENTRAL ATACAMA DESERT, CHILE".GEOMORPHOLOGY 393(2021).