Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas
In this paper, we use morphological and numerical methods to test the hypothesis that seasonally formed fracture patterns in the Martian polar regions result from the brittle failure of seasonal CO2 slab ice. The observations by the High Resolution Imaging Science Experiment (HiRISE) of polar region...
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2012
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ftdatacite:10.7892/boris.10221 2023-05-15T16:40:38+02:00 Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas Thomas, Nicolas Portyankina, Ganna Hansen, Candice T. J. Aye, Klaus-Michael Pommerol, Antoine 2012 application/pdf https://dx.doi.org/10.7892/boris.10221 http://boris.unibe.ch/10221/ en eng American Geophysical Union info:eu-repo/semantics/openAccess Text article-journal ScholarlyArticle 2012 ftdatacite https://doi.org/10.7892/boris.10221 2021-11-05T12:55:41Z In this paper, we use morphological and numerical methods to test the hypothesis that seasonally formed fracture patterns in the Martian polar regions result from the brittle failure of seasonal CO2 slab ice. The observations by the High Resolution Imaging Science Experiment (HiRISE) of polar regions of Mars show very narrow dark elongated linear patterns that are observed during some periods of time in spring, disappear in summer and re-appear again in the following spring. They are repeatedly formed in the same areas but they do not repeat the exact pattern from year to year. This leads to the conclusion that they are cracks formed in the seasonal ice layer. Some of models of seasonal surface processes rely on the existence of a transparent form of CO2 ice, so-called slab ice. For the creation of the observed cracks the ice is required to be a continuous media, not an agglomeration of relatively separate particles like a firn. The best explanation for our observations is a slab ice with relatively high transparency in the visible wavelength range. This transparency allows a solid state green-house effect to act underneath the ice sheet raising the pressure by sublimation from below. The trapped gas creates overpressure and the ice sheet breaks at some point creating the observed cracks. We show that the times when the cracks appear are in agreement with the model calculation, providing one more piece of evidence that CO2 slab ice covers polar areas in spring. Text Ice Sheet DataCite Metadata Store (German National Library of Science and Technology) |
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DataCite Metadata Store (German National Library of Science and Technology) |
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ftdatacite |
language |
English |
description |
In this paper, we use morphological and numerical methods to test the hypothesis that seasonally formed fracture patterns in the Martian polar regions result from the brittle failure of seasonal CO2 slab ice. The observations by the High Resolution Imaging Science Experiment (HiRISE) of polar regions of Mars show very narrow dark elongated linear patterns that are observed during some periods of time in spring, disappear in summer and re-appear again in the following spring. They are repeatedly formed in the same areas but they do not repeat the exact pattern from year to year. This leads to the conclusion that they are cracks formed in the seasonal ice layer. Some of models of seasonal surface processes rely on the existence of a transparent form of CO2 ice, so-called slab ice. For the creation of the observed cracks the ice is required to be a continuous media, not an agglomeration of relatively separate particles like a firn. The best explanation for our observations is a slab ice with relatively high transparency in the visible wavelength range. This transparency allows a solid state green-house effect to act underneath the ice sheet raising the pressure by sublimation from below. The trapped gas creates overpressure and the ice sheet breaks at some point creating the observed cracks. We show that the times when the cracks appear are in agreement with the model calculation, providing one more piece of evidence that CO2 slab ice covers polar areas in spring. |
format |
Text |
author |
Thomas, Nicolas Portyankina, Ganna Hansen, Candice T. J. Aye, Klaus-Michael Pommerol, Antoine |
spellingShingle |
Thomas, Nicolas Portyankina, Ganna Hansen, Candice T. J. Aye, Klaus-Michael Pommerol, Antoine Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
author_facet |
Thomas, Nicolas Portyankina, Ganna Hansen, Candice T. J. Aye, Klaus-Michael Pommerol, Antoine |
author_sort |
Thomas, Nicolas |
title |
Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
title_short |
Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
title_full |
Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
title_fullStr |
Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
title_full_unstemmed |
Polygonal cracks in the seasonal semi-translucent CO2 ice layer in Martian polar areas |
title_sort |
polygonal cracks in the seasonal semi-translucent co2 ice layer in martian polar areas |
publisher |
American Geophysical Union |
publishDate |
2012 |
url |
https://dx.doi.org/10.7892/boris.10221 http://boris.unibe.ch/10221/ |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.7892/boris.10221 |
_version_ |
1766031037274521600 |