Eruptions Word of the Day: Harmonic Tremor and Tornillos.
There are few methods that get as much attention in the world of volcanic monitoring than measuring the release of seismic energy. Not only does seismicity inform us on the depth and location of magma movement, but it can also give vital clues to how close a volcano is to eruption. Earthquakes might begin to occur in swarms – hundreds to thousands of separate earthquake events that record magma on the move at depth. These earthquakes might change in depth over months, weeks, days or less as the magma rises underneath a potentially active volcano. However, seismic signals can also be very difficult to interpret because many times the seismic information does not have single source – that is there are potentially multiple events that can produce seismic events recorded under volcanoes.