An Earlier Suggestion of A Frozen Body of Water in Athabasca and Marte Valles

Morphology of Fresh Outflow Channel Deposits on Mars, Rice,J.W.,Jr.; Parker,T.J.; Russell,A.J.; Knudsen,O., 33rd Annual Lunar and Planetary Science Conference, March 11-15, 2002, Houston, Texas, abstract no.2026

“Perhaps the most intriguing and debatable landforms in the region are the plates and ridges seen within the channel margins of Athabasca and Marte Valles. The plates can be up to 5 km diameter and have been rafted apart. The plates can be ‘jigsaw fitted’ back in place. The ridges are sinuous and up to 10 m wide and a few meters high.”

“We favor an ice-rich fluvial (hyperconcentrated) flow emplacement process for the plate and ridge forming materials. Simply stated, this is what a fresh outflow channel deposit would look like. The outflow event deposited ice rich sediment in a low gradient plain that then froze in place. We interpret the ridges to be ice pressure ridges analogous in size to ridges formed in pack ice. The plates were slabs of sediment rich ice rafted along in the debris flow. As the surface ice sublimated away it left behind a cast that was filled with the muddy sediment. It is possible that shallow ground ice is still present if a sufficient depth of insulating mantle material is covering the ice.”