Cracks in a Debris Apron

The objective of this observation is to investigate the nature of large fissures in a smooth apron around a mound in the Phlegra region.

The apron could be (or could have been) ice-rich, so one possibility is that the fissures are related to ice loss. Based on radar data from MRO combined with studies of the region’s geology from other orbiters, scientists think that extensive glaciers covered this region several hundred million years ago.

This caption is based on the original science rationale.

Written by: HiRISE Science Team (audio: Tre Gibbs)   (11 March 2015)

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Image: NASA/JPL/University of Arizona