Durham University GEOL 4061 Frontiers of Earth Science. Do Plumes Exist?. Gillian R. Foulger. What is a plume?. A plume is a bottom-heated convective upwelling that rises through its own thermal buoyancy.
Frontiers of Earth Science
Gillian R. Foulger
Griffiths & Campbell (1990):
Plumes created by injecting syrup/water mix (to be less dense) into the tank.
However, study of melting anomaly origins has not progressed because of “plume belief”
What does “hot” mean?
200 - 300 K is the minimum required for a plume
How hot are “hot spots”?
Cordery et al. (1997)
Hawaii relative to Atlantic “hot spots”
Ritsema et al. 1999
= variable magmatic fecundity
Bertram Schott et al. (2000)
A 30/70 eclogite-peridotite mixture can generate several times as much melt as peridotite
Closure of Iapetus
Extensional stresses occur at RT and RRR intersections and can permit volcanism
e.g., Amsterdam/St. Paul, Easter
Recent modeling suggests that meteorites 10 - 30 km in diameter could form LIPs
e.g., Bushveldt, Ontong Java
Overthickening of the crust causes eclogitisation, delamination and triggers LIP volcanism
e.g., Siberian Traps