出典:Wikipedia
出典:『Wikipedia』 (2011/05/22 19:11 UTC 版)
A hot blob is a body of magma which rises by convection to the surface of the mantle. This causes a pronounced uplift of the overlying crust, of the order of around a kilometre. The blob then spreads slowly over 1 - 2 million years, becoming a ring shaped ripple and decreasing in height as it does so.