Types of Earthquake - John Seach

johnVolcanic, Tectonic, Volcano-tectonic, Explosion.

Volcanic explosion earthquakes accompanying explosive eruptions are viewed as representing an abrupt release of pressurized magma beneath a volcano through a vent.
The seismic magnitude of the largest event for each volcano is essentially proportional to the cross-sectional area of the vent for vent radii ranging from 10 to 600 m.