DOI: 10.1016/j.epsl.2018.07.040
Scopus记录号: 2-s2.0-85052309504
论文题名: The Hypanis Valles delta: The last highstand of a sea on early Mars?
作者: Fawdon P. ; Gupta S. ; Davis J.M. ; Warner N.H. ; Adler J.B. ; Balme M.R. ; Bell J.F. ; III ; Grindrod P.M. ; Sefton-Nash E.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 500 起始页码: 225
结束页码: 241
语种: 英语
英文关键词: delta
; fluvial
; Mars
; Mars geology
; Mars ocean
Scopus关键词: Catchments
; Geology
; delta
; Dichotomy boundary
; fluvial
; Fluvial channels
; Geological history
; Horizontal layers
; Mars
; Mars ocean
; Sediments
; avulsion
; delta
; fluvial deposit
; lowland environment
; Mars
; topography
; Hesperia
英文摘要: One of the most contentious hypotheses in the geological history of Mars is whether the northern lowlands ever contained an oceanic water body. Arguably, the best evidence for an ocean comes from the presence of sedimentary fans around Mars’ dichotomy boundary, which separates the northern lowlands from the southern highlands. Here we describe the palaeogeomorphology of the Hypanis Valles sediment fan, the largest sediment fan complex reported on Mars (area >970 km2). This has an extensive catchment (4.6×105 km2) incorporating Hypanis and Nanedi Valles, that we show was active during the late-Noachian/early-Hesperian period (∼3.7 Ga). The fan comprises a series of lobe-shaped sediment bodies, connected by multiple bifurcating flat-topped ridges. We interpret the latter as former fluvial channel belts now preserved in inverted relief. Meter-scale-thick, sub-horizontal layers that are continuous over tens of kilometres are visible in scarps and the inverted channel margins. The inverted channel branches and lobes are observed to occur up to at least 140 km from the outlet of Hypanis Valles and descend ∼500 m in elevation. The progressive basinward advance of the channellobe transition records deposition and avulsion at the margin of a retreating standing body of water, assuming the elevation of the northern plains basin floor is stable. We interpret the Hypanis sediment fan to represent an ancient delta as opposed to a fluvial fan system. At its location at the dichotomy boundary, the Hypanis Valles fan system is topographically open to Chryse Planitia – an extensive plain that opens in turn into the larger northern lowlands basin. We conclude that the observed progradation of fan bodies was due to basinward shoreline retreat of an ancient body of water which extended across at least Chryse Planitia. Given the open topography, it is plausible that the Hypanis fan system records the existence, last highstand, and retreat of a large sea in Chryse Planitia and perhaps even an ocean that filled the northern plains of Mars. © 2018 The Authors Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109686
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, United Kingdom; Department of Earth Sciences and Engineering, Imperial College London, London, SW7 2AZ, United Kingdom; Department of Earth Sciences, Natural History Museum, Cromwell Road, Kensington, London, SW7 5BD, United Kingdom; Department of Geological Sciences, Integrated Science Center, State University of New York at Geneseo, One College Circle, Geneseo, NY 14454, United States; School of Earth and Space Exploration, Arizona State University, ISTB4 Room 795, 781 Terrace Mall, Tempe, AZ 85287, United States; European Space Research and Technology Centre, Keplerlaan 1, Noordwijk, AZ 2201, Netherlands
Recommended Citation:
Fawdon P.,Gupta S.,Davis J.M.,et al. The Hypanis Valles delta: The last highstand of a sea on early Mars?[J]. Earth and Planetary Science Letters,2018-01-01,500