Mars From Afar
Volcanic Vent
This deep trough lies in the Tharsis region of Mars, home to several
of the largest shield volcanoes in the solar system. It is a
volcanic vent, where lava erupted long ago. The shallow, scalloped
depressions in the middle and left (west) of the image may have been
lava lakes that emptied into the vent at the end of the eruption
that created the vent. To the right (east) are two channels that
once likely drained the vent. Once deeper and narrower, the vent
became more trough-like as material eroded from its sides and fell
to its floor. The image was taken on December 6, 2006, by the High
Resolution Imaging Science Experiment.