Surface and subsurface study of unusual ice scarps, southern polar cap of Mars
The southern polar cap of Mars, known as Planum Australe, is a 1.6 x 106 km3 ice sheet made of water ice with a 0 to 15 % dust rate. It is structured of isochrone layers deposited over several hundreds of millions of years, and reaching 3700 m of maximum thickness. Those features make the cap compar...
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ftunigrenoble:oai:HAL:insu-00361510v1 2024-05-12T08:05:25+00:00 Surface and subsurface study of unusual ice scarps, southern polar cap of Mars Grima, Cyril Kofman, Wlodek Mouginot, Jeremie Servain, Anthony Beck, Pierre Pommerol, Antoine Hérique, Alain Seu, Roberto Laboratoire de Planétologie de Grenoble (LPG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) Centre National de la Recherche Scientifique (CNRS) Dipartimento INFOCOM Roma Università degli Studi di Roma "La Sapienza" = Sapienza University Rome (UNIROMA) Montréal, Canada 2008-07-13 https://insu.hal.science/insu-00361510 en eng HAL CCSD insu-00361510 https://insu.hal.science/insu-00361510 37th COSPAR Scientific Assembly https://insu.hal.science/insu-00361510 37th COSPAR Scientific Assembly, Jul 2008, Montréal, Canada info:eu-repo/semantics/conferenceObject Conference papers 2008 ftunigrenoble 2024-04-18T03:07:37Z The southern polar cap of Mars, known as Planum Australe, is a 1.6 x 106 km3 ice sheet made of water ice with a 0 to 15 % dust rate. It is structured of isochrone layers deposited over several hundreds of millions of years, and reaching 3700 m of maximum thickness. Those features make the cap comparable to the continental ice sheets on Earth. However, low surface temperatures (155 K), weak atmospheric pressure (0.008 bars) and other typical Martian parameters could make the ice to have mechanical and dynamic behaviors, at any scales, somewhat different to those known under terrestrial conditions. Such behaviors remain to be detected. Unusual ice scarps are observed over a well defined region of Planum Australe. They have a 500 m average height and a typical length of about 30 km. Their particular size and shape are unknown neither on the northern Martian cap nor on the Earth. So far few studies, based on analysis of low resolution images, suggested a wind formation process. The sounding radar SHARAD onboard the NASA's Mars Reconnaissance Orbiter spacecraft, is able to penetrate as far as 1000 m deep into water ice materials with a vertical x alongtrack resolution of 7 m x 300 m respectively. This dataset is an opportunity to study the subsurface structure of those unusual scarps. We will present a work aiming to draw up a complete description of those objects on and below the surface. The obtained profile could be better explained by a more brutal event than a wind-formed mechanism. Different suggestions for this formation process will be exposed. We will emphasize that to be fully explained, the formation process needs an effort to better understand the rheology of Martian ices. Those results will be presented in a regional context. Conference Object Ice Sheet Université Grenoble Alpes: HAL Canada |
institution |
Open Polar |
collection |
Université Grenoble Alpes: HAL |
op_collection_id |
ftunigrenoble |
language |
English |
description |
The southern polar cap of Mars, known as Planum Australe, is a 1.6 x 106 km3 ice sheet made of water ice with a 0 to 15 % dust rate. It is structured of isochrone layers deposited over several hundreds of millions of years, and reaching 3700 m of maximum thickness. Those features make the cap comparable to the continental ice sheets on Earth. However, low surface temperatures (155 K), weak atmospheric pressure (0.008 bars) and other typical Martian parameters could make the ice to have mechanical and dynamic behaviors, at any scales, somewhat different to those known under terrestrial conditions. Such behaviors remain to be detected. Unusual ice scarps are observed over a well defined region of Planum Australe. They have a 500 m average height and a typical length of about 30 km. Their particular size and shape are unknown neither on the northern Martian cap nor on the Earth. So far few studies, based on analysis of low resolution images, suggested a wind formation process. The sounding radar SHARAD onboard the NASA's Mars Reconnaissance Orbiter spacecraft, is able to penetrate as far as 1000 m deep into water ice materials with a vertical x alongtrack resolution of 7 m x 300 m respectively. This dataset is an opportunity to study the subsurface structure of those unusual scarps. We will present a work aiming to draw up a complete description of those objects on and below the surface. The obtained profile could be better explained by a more brutal event than a wind-formed mechanism. Different suggestions for this formation process will be exposed. We will emphasize that to be fully explained, the formation process needs an effort to better understand the rheology of Martian ices. Those results will be presented in a regional context. |
author2 |
Laboratoire de Planétologie de Grenoble (LPG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) Centre National de la Recherche Scientifique (CNRS) Dipartimento INFOCOM Roma Università degli Studi di Roma "La Sapienza" = Sapienza University Rome (UNIROMA) |
format |
Conference Object |
author |
Grima, Cyril Kofman, Wlodek Mouginot, Jeremie Servain, Anthony Beck, Pierre Pommerol, Antoine Hérique, Alain Seu, Roberto |
spellingShingle |
Grima, Cyril Kofman, Wlodek Mouginot, Jeremie Servain, Anthony Beck, Pierre Pommerol, Antoine Hérique, Alain Seu, Roberto Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
author_facet |
Grima, Cyril Kofman, Wlodek Mouginot, Jeremie Servain, Anthony Beck, Pierre Pommerol, Antoine Hérique, Alain Seu, Roberto |
author_sort |
Grima, Cyril |
title |
Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
title_short |
Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
title_full |
Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
title_fullStr |
Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
title_full_unstemmed |
Surface and subsurface study of unusual ice scarps, southern polar cap of Mars |
title_sort |
surface and subsurface study of unusual ice scarps, southern polar cap of mars |
publisher |
HAL CCSD |
publishDate |
2008 |
url |
https://insu.hal.science/insu-00361510 |
op_coverage |
Montréal, Canada |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
37th COSPAR Scientific Assembly https://insu.hal.science/insu-00361510 37th COSPAR Scientific Assembly, Jul 2008, Montréal, Canada |
op_relation |
insu-00361510 https://insu.hal.science/insu-00361510 |
_version_ |
1798847705949143040 |