Two
projects are currently underway - one studying the Ontong
Java Plateau (SW Pacific) and one studying the Kerguelen
Plateau (southern Indian Ocean). LIPs are studied
because
they cannot be generated within the normal plate tectonic framework and
working models rely on plume volcanism. This involves rising
plume
heads from either the 670 km discontinuity or the core-mantle
boundary. Heat
transferred across such a boundary causes instability in the overlying
layer resulting in the rise of the heated mass. Therefore, plumes
have implications for how the Earth is evolving. The amount of
magma
generated and the short time-scale in which it is erupted has PROFOUND
implications for how the atmosphere is affected and many mass
extinctions
have been correlated with eruption of LIPs.
Planetary applications of plumes can be seen on the Moon where Lunar Prospector has mapped out a Th anomaly or "hotspot" on the lunar nearside, and also on Mars where the largest volcano in the solar systam, Olympus Mons, is situated and proposed to form by plume volcanism
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