	Vailulu'u is an active volcano, with earthquakes, volcanic eruptions and hydrothermal activity recorded. In particular, the seamount is a site with common earthquakes in this otherwise mostly aseismic part of the Pacific Plate and away from the earthquakes of the Tonga Trench, recording an average 4 earthquakes per day. Seismic swarms were observed in 1973 and 1995; an earthquake swarm took place in 2000. The hypocentres of these earthquakes appear to coincide with the hydrothermal areas and the earthquakes correlate with the southeastern ridge, which is a rift zone.