An injection is the magma forced into fractures. Injections of magma can set two plates apart in a diverging motion. This is a cause for plate movement.
A sill is a small intrusion parallel to existing rock. Sills can store magma channels.
are small intrusions cutting across existing rock. can transport magma through volcano bases into levels of geological plates. They act as transportation for magma.
Plutons are the general term for igneous intrusion. Plutons are congealed masses that sit near the bases of volcanoes. They can be found near sills, and magma chambers.