What They Are • Their Characteristics • How They Behave • How We Know What We Do • Why You Should Know Hot Spots
Definition • A volcanic center, 60 to 120 miles (100 to 200 km) across and persistent for at least a few tens of million of years, that is thought to be the surface expression of a persistent rising plume of hot mantle material. Hot spots are not linked to arcs and may not be associated with ocean ridges.
Latest Ideas • Hot Spots may be related to huge blobs of magma that rise from within the mantle and pool against the base of the lithosphere • May not be associated with “plumes”
Mantle Plume Concept Phasing Out? Some geologists think that the mantle plume idea isn’t holding up; they think they can explain magma melting by drops in pressure, rather than deep-seated heat sources…
Summary • ~50-100 miles wide • Live for 10’s of millions of years • Are fixed in the mantle • Are NOT linked to arcs • May not be associated with ridges • Have a life cycle • Leave a track of volcanic features on the landscape (or seascape)