The territory experiences frequent seismic and volcanic activity. Located in the east of the Philippine Sea, the Benham Plateau is an underwater region with about 20 earthquakes recorded daily, although most are too weak to be felt.
The last recorded major earthquake was on the island of Luzon in 1990 (a magnitude 7.7 quake on the Richter scale, which killed 1621 people).
There are fourteen active volcanoes in the archipelago, these include Mayon and Taal, which have a high explosiveness rating (85 degrees on the 100-degree scale). In 1991 there was an eruption of the Pinatubo volcano on the island of Luzon, which killed 600 people and destroyed 100.000 hectares of farmland.
