The (missing) erosional record of warm-based glaciation on early Mars

The lack of evidence for large-scale glacial erosion on Mars has led to the belief that any ice sheet that may have existed had to be frozen to the ground. We challenge this argument, suggesting instead that the fingerprints of Martian warm-based ice masses should be the remnants of their drainage systems, including channel networks and eskers, instead of the large scoured fields generally associated with terrestrial Quaternary glaciation. Our results use the terrestrial glacial hydrology framework to interrogate how the Martian lower surface gravity should affect the state and evolution of the glacial drainage system, ice sliding velocity, and the rates of glacial erosion. Taking as reference the scale and characteristics of the ancient southern circumpolar ice sheet that deposited the Dorsa Argentea formation, we compare the theoretical behavior of geometrically identical ice sheets on Mars and Earth and show that, whereas on Earth glacial drainage is predominantly inefficient, enhancing ice sliding and producing characteristically scoured glacial landscapes, on Mars the lower gravity favors the formation of efficient subglacial channelized drainage. The apparent lack of large-scale glacial fingerprints on Mars, such as scouring marks, drumlins, lineations, etc., is thus to be expected.