THEMIS Image of the Day, May 23, 2018. Located west of the Elysium Volcanic complex, Hebrus Valles is a complex channel system that flowed to the north. In this VIS image the channel features have the appearance of a channel formed by liquid flow.
In other portions of the valles, there are pits and collapse features which appear to have formed by material falling into subsurface voids. This is a common feature in regions of volcanic activity where lava tubes run below the surface. Both water and lava probably contributed to the formation of Hebrus Valles.
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