Exposed Bedrock in the Koval’sky Impact Basin

This image shows partially exposed bedrock within the Koval’sky impact basin, which is on the outskirts of the extensive lava field of Daedalia Planum . Daedalia Planum is located southwest of Arsia Mons, which may be the source responsible for filling the crater with lava flows and ash deposits.

On one side, we see bright bedrock with scattered dark blue spots. The dark blue spots are boulders shedding from the outcrops. The color range of the bedrock provides some information on its composition. The blue color is indicative of the presence of iron-rich minerals that are generally not oxidized (i.e., rusted), unlike most of the ruddy Martian surface. Volcanic rocks are common on Mars. Possible candidate minerals for the bluish materials are often consistent with iron-rich minerals, such as pyroxene and olivine. The ridges may represent remnants of the original surface of the lava flows that filled the Koval’sky impact basin.

NB: The region is named for M.A. Koval’sky, a Russian astronomer .

Written by: Gavin Tolometti, Livio L. Tornabene, Jon Kissi and Zach Morse (audio: Tre Gibbs)  (27 June 2017)

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Image: NASA/JPL/University of Arizona