Exploratour - Volcanoes of the Solar System
This picture of the Moon shows the lunar Maria. These dark areas are thought to be the remains of ancient lava flows on the moon, indicating that there may once have been volcanism there. The volcanism of the moon is thought to be of the sort where old impact basins were flooded by lava seeping up from below. This is the mechanism which is thought to have created the Maria which we see today.
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