Where volcanoes meet glaciers, lakes often form. This happens in many places on Earth and in at least one place off it: Arsia Mons, Mars.
Arsia Monsis one of the largest mountains in the solar system. Wispy water-ice clouds gather near its peak during the Martian afternoon. While it is only the third tallest volcano on Mars, Arsia Mons is 300 km (186 miles) wide and twice as tall as Mount Everest. If Mount Everest were to suddenly erupt today, some of the vast glaciers on its surface would melt producing floods, lakes and debris plains. We now have reason to believe this is exactly what happened on Mars when Arsia Mons was active 200 million years ago.
The evidence for these events lies along the northwest flank of the volcano. Fan-shaped-deposits (FSDs) seen by the Mars Reconnaissance Orbiter bear a striking resemblance to alluvial deposits. Such deposits are found on Earth in Death Valley, in the mountains of France, and in many places prone to flash-flooding or glacial melting. In 2012, the Mars Curiosity rover found fluvial deposits in the Gale crater. In a recently published study Kathleen Scanlon and her colleagues at Brown, Boston University, and Lancaster University in the UK showed how the FSDs and other geologic features seen near Arsia Mons are best explained by glacial deposits and enormous quantities of water.
"The term 'fan shaped deposit' usually refers to the whole glacial deposit, which was mostly created by ice that was frozen to its bed," said Scanlon, "While we think all the glaciovolcanic edifices in the FSD had englacial lakes surrounding them, the outflow channels at the northwestern edge of the deposit are the only evidence we have for the flow, per se, of large quantities of water here."
Read more at: http://phys.org/news/2014-06-ice-forge-reservoir-life-mars.html#jCp
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