| Title: |
The Dynamics of CO$_ 2$‐Driven Granular Flows in Gullies on Mars |
| Authors: |
Roelofs, Lonneke; Conway, Susan J.; van Dam, Bas; van Eijk, Arjan; Merrison, Jonathan, P; Iversen, Jens, Jacob; Sylvest, Matthew; Patel, Manish, R; Markies, Henk; van Maarseveen, Marcel; Mcelwaine, Jim; Kleinhans, Maarten, G; de Haas, Tjalling |
| Contributors: |
Department of Physical Geography Utrecht; Universiteit Utrecht / Utrecht University Utrecht; Laboratoire de Planétologie et Géosciences UMR_C 6112 (LPG); Le Mans Université (UM)-Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST); Nantes Université - pôle Sciences et technologie; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ); Aarhus University Aarhus; The Open University Milton Keynes, UK (OU); Department of Earth Sciences Durham; Durham University; CNRS INSU Programme Nationale de Planétologie; CNES |
| Source: |
ISSN: 2169-9097. |
| Publisher Information: |
CCSD; Wiley-Blackwell |
| Publication Year: |
2024 |
| Collection: |
Université de Nantes: HAL-UNIV-NANTES |
| Subject Terms: |
[SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology; [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology |
| Description: |
International audience ; Martian gullies are landforms consisting of an erosional alcove, a channel, and a depositional apron. A significant proportion of Martian gullies at the mid‐latitudes is active today. The seasonal sublimation of CO$_ 2$ ice has been suggested as a driver behind present‐day gully activity. However, due to a lack of in situ observations, the actual processes causing the observed changes remain unresolved. Here, we present results from flume experiments in environmental chambers in which we created CO$_ 2$‐driven granular flows under Martian atmospheric conditions. Our experiments show that under Martian atmospheric pressure, large amounts of granular material can be fluidized by the sublimation of small quantities of CO$_ 2$ ice in the granular mixture (only 0.5% of the volume fraction of the flow) under slope angles as low as 10°. Dimensionless scaling of the CO$_ 2$‐driven granular flows shows that they are dynamically similar to terrestrial two‐phase granular flows, that is, debris flows and pyroclastic flows. The similarity in flow dynamics explains the similarity in deposit morphology with levees and lobes, supporting the hypothesis that CO$_ 2$‐driven granular flows on Mars are not merely modifying older landforms, but they are actively forming them. This has far‐reaching implications for the processes thought to have formed these gullies over time. For other planetary bodies in our solar system, our experimental results suggest that the existence of gully like landforms is not necessarily evidence for flowing liquids but that they could also be formed or modified by sublimation‐driven flow processes. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1029/2024JE008319 |
| Availability: |
https://hal.science/hal-04667675; https://hal.science/hal-04667675v1/document; https://hal.science/hal-04667675v1/file/JGR%20Planets%20-%202024%20-%20Roelofs%20-%20The%20Dynamics%20of%20CO2%E2%80%90Driven%20Granular%20Flows%20in%20Gullies%20on%20Mars.pdf; https://doi.org/10.1029/2024JE008319 |
| Rights: |
https://about.hal.science/hal-authorisation-v1/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.80BAB054 |
| Database: |
BASE |