DOI: 10.1038/ngeo2917
论文题名: Formation of recurring slope lineae on Mars by rarefied gas-triggered granular flows
作者: Schmidt F. ; Andrieu F. ; Costard F. ; Kocifaj M. ; Meresescu A.G.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2017
卷: 10, 期: 4 起始页码: 270
结束页码: 273
语种: 英语
Scopus关键词: avalanche
; dark
; flow measurement
; granular medium
; irradiation
; liquid
; Mars
; mathematical analysis
; slope
; solar radiation
; water
英文摘要: Active dark flows known as recurring slope lineae have been observed on the warmest slopes of equatorial Mars. The morphology, composition and seasonality of the lineae suggest a role of liquid water in their formation. However, internal and atmospheric sources of water appear to be insufficient to sustain the observed slope activity. Experimental evidence suggests that under the low atmospheric pressure at the surface of Mars, gas can flow upwards through porous Martian soil due to thermal creep under surface regions heated by the Sun, and disturb small particles. Here we present numerical simulations to demonstrate that such a dry process involving the pumping of rarefied gas in the Martian soil due to temperature contrasts can explain the formation of the recurring slope lineae. In our simulations, solar irradiation followed by shadow significantly reduces the angle of repose due to the resulting temporary temperature gradients over shaded terrain, and leads to flow at intermediate slope angles. The simulated flow locations are consistent with observed recurring slope lineae that initiate in rough and bouldered terrains with local shadows over the soil. We suggest that this dry avalanche process can explain the formation of the recurring slope lineae on Mars without requiring liquid water or CO 2 frost activity. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/105806
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: GEOPS, Univ. Paris-Sud, CNRS, Université Paris-Saclay, Rue du Belvédère, Bât. 504-509, Orsay, France; ICA, Slovak Academy of Sciences, Dubravska Road 9, Bratislava, Slovakia; Faculty of Mathematics, Physics, and Informatics, Comenius University, Mlynska Dolina, Bratislava, Slovakia
Recommended Citation:
Schmidt F.,Andrieu F.,Costard F.,et al. Formation of recurring slope lineae on Mars by rarefied gas-triggered granular flows[J]. Nature Geoscience,2017-01-01,10(4)