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Basal melting of snow on early Mars: A possible origin of some valley networks

M. H. Carr·J. W. Head
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Abstract

Valley networks appear to be cut by liquid water, yet simulations suggest that early Mars could not have been warmed enough by a CO 2 -H 2 O greenhouse to permit rainfall. The vulnerability of an early atmosphere to impact erosion, the likely rapid scavenging of CO 2 from the atmosphere by weathering, and the lack of detection of weathering products all support a cold early Mars . We explore the hypothesis that valley networks could have formed as a result of basal melting of thick snow and ice deposits. Depending on the heat flow, an early snowpack a few hundred meters to a few kilometers thick could undergo basal melting , providing water to cut valley networks .

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M. H. Carr, J. W. Head. 2003-12-17. Basal melting of snow on early Mars: A possible origin of some valley networks. https://doi.org/10.1029/2003gl018575

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