LARGE IGNEOUS PROVINCES (LIPs)

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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