release of underwater gas deposits has played its part in previous
periods of the Earth's history, as noted, during the Permian extinction
of 251 million years ago. With a global increase of 6 degrees, the
'super hurricanes' raised by warming oceans, 20 metres raised, triggered
floods that nothing could survive.
Amongst the evidence
of former water activity on Mars, there are geological features
which describe floods of enormous proportions, far exceeding anything
so far seen on this Earth.
One of these features is the channel of Ma'adim Valles, one of Mars'
major canyons, which opens into Gusev crater, a 160 kilometer wide
basin in the cratered uplands of the southern hemisphere, where
the rover 'Spirit' found evidence of water. It is believed that
a large lake in the southern highlands of Mars overflowed about
3.5 billion years ago, at the beginning of the Siderikan era and
the end of volcanism during the Theikian, gouging out the canyon
as the torrent headed north and then spilled into the crater, forming
a new lake.