SAN ANTONIO, Zambales—Four new volcanic earthquakes were registered at Mt. Pinatubo Monday (July 19), according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
The seismic activities kept the volcano under alert level or low-level unrest with no indication of an imminent eruption.
Phivolcs has been conducting 24-hour monitoring of Mt. Pinatubo, where earthquakes, as many as nine in a day, were observed in the last two weeks.
The earthquakes were first recorded in the volcano in January and became frequent until March, prompting the Phivolcs to raise the alert level at Mt. Pinatubo from zero to one.
It was the first time that Phivolcs raised the alert level at Mt. Pinatubo since it was placed on normal status in 1996.