Viscosity		the internal resistance to flow.
Pluton		the largest plutons.
Batholith		pluton that forms when magma intrudes.
Stock		pluton that cuts across pre-existing rocks.
Laccolith		mushroom shaped pluton.
Sill		larger depressions which can be 50 km in diameter.
Dike		irregularly shaped plutons.
Vent		an opening in the crust.
Crater		intrusive igneous rock bodies.
Caldera		bowl shaped depression.