Quantifying the Environmental Response to Deglaciation in Martian Craters
Mentor Information
Joseph Panzik (School of Geosciences)
Description
The present day climate of Mars has been delineated by a hyperarid climate conditions with glacial periods primarily controlled by variations in obliquity. In the past ~5 million years, the mean value of obliquity of Mars has decreased from ~35° to the current ~25°, a change which is interpreted to cause glacial ice to move from the mid-latitudes to the polar regions, resulting in deglaciation of the midlatitudes. On Earth, environments that experience deglaciation are classified as undergoing a paraglacial period, where the landscape is recovering from the effects of glaciation. This results in increased sediment transport and the formation of a diagnostic set of geologic features. On the surface of Mars, this diagnostic set of features are also formed after glaciers migrate away, including gullies, spatulate depressions, washboard terrain, and polygonal terrain. We mapped the distribution of these features within craters using CTX and HiRISE data. We also quantified various characteristics of each feature, as well as identified the orientation aspect of said features. We found that the spatial extent of paraglacial features increases with increasing crater diameter. The data collected supports the interpretation that glaciers are no longer active at the mid-latitudes, while paraglaciation remains the prominent system these environments have recently experienced. Since the extent of paraglaciation was not equal across the craters analyzed, paraglaciation is interpreted to experience regional variability. Implications for the constraining of past and present climatic systems on Mars will be gained by further assessing the extent of paraglaciation on the Red Planet.
Quantifying the Environmental Response to Deglaciation in Martian Craters
The present day climate of Mars has been delineated by a hyperarid climate conditions with glacial periods primarily controlled by variations in obliquity. In the past ~5 million years, the mean value of obliquity of Mars has decreased from ~35° to the current ~25°, a change which is interpreted to cause glacial ice to move from the mid-latitudes to the polar regions, resulting in deglaciation of the midlatitudes. On Earth, environments that experience deglaciation are classified as undergoing a paraglacial period, where the landscape is recovering from the effects of glaciation. This results in increased sediment transport and the formation of a diagnostic set of geologic features. On the surface of Mars, this diagnostic set of features are also formed after glaciers migrate away, including gullies, spatulate depressions, washboard terrain, and polygonal terrain. We mapped the distribution of these features within craters using CTX and HiRISE data. We also quantified various characteristics of each feature, as well as identified the orientation aspect of said features. We found that the spatial extent of paraglacial features increases with increasing crater diameter. The data collected supports the interpretation that glaciers are no longer active at the mid-latitudes, while paraglaciation remains the prominent system these environments have recently experienced. Since the extent of paraglaciation was not equal across the craters analyzed, paraglaciation is interpreted to experience regional variability. Implications for the constraining of past and present climatic systems on Mars will be gained by further assessing the extent of paraglaciation on the Red Planet.
