Water, ice, their coupled dynamics and their effects on the martian landscape
Anna Grau Galofre
My talk will explore the diverse dynamics of water ice on the surface of Earth and Mars, and the distinctive landscapes that may arise from this difference.
In detail, geological evidence hints that Mars may have hosted surface liquid water in the remote past, pointing at warmer conditions, a thicker early atmosphere, and a larger primitive global water budget.
In contrast, Mars hosts nowadays a global cryosphere, freezing surface temperatures, a thin atmosphere, and a much smaller water inventory. The transition between early and current martian environments should have led –somewhere, at some point- to the build-up of ice masses, with liquid water stable under glacial deposits. However, the geological record is seemingly inconsistent with water-ice interactions, with most of the glacio-geological record pointing at cold-based ice deposits.
The fact that this dearth of ‘classical’ glacial landforms actually corresponds to a lack of glacial ‘sliding’ landforms suggests that differences may exist between the geological record of Martian and terrestrial ice masses – hinting at differing ice dynamics. My work uses ice sheet and glacial hydrology models, complemented with observations of terrestrial analogues, to understand what type of geological record we should expect glaciers and ice sheets on Mars to hold.
My findings suggest that the glacial record on Mars was likely dominated by fluvioglacial processes, incising valleys and depositing esker ridges, and that the presence of ‘classical’ glacial landforms should be scarce.
Sorbonne Université – Campus Pierre et Marie Curie
4, place Jussieu 75005 Paris
LMD, Salle 313, couloir 45-55, 3e étage