Taal Volcano is a complex volcano located on the island of Luzon in the Philippines. It is the second most active volcano in the Philippines with 33 historical eruptions. All of these eruptions are concentrated on Volcano Island, an island near the middle of Taal Lake. The lake partially fills Taal Caldera, which was formed by prehistoric eruptions between 140,000 to 5,380 BP. Viewed from Tagaytay Ridge, Taal Volcano and Lake presents one of the most picturesque and attractive views in the Philippines. It is located about 50 km south of the capital of the country, the city of Manila.
The volcano had several violent eruptions in the past causing loss of life in the island and the populated areas surrounding the lake, with the death toll estimated at around 5,000 to 6,000. Because of its proximity to populated areas and its eruptive history, the volcano was designated a Decade Volcano, worthy of close study to prevent future natural disasters. All volcanoes of the Philippines are part of the Pacific Ring of Fire.
Geography
Taal Volcano and Lake are wholly located in the province of Batangas. The northern half of Volcano Island falls under the jurisdiction of the lake shore town of Talisay, and the southern half to San Nicolas. The other towns that encircle Taal Lake include Tanauan, Talisay, Laurel, Agoncillo, Santa Teresita, Alitagtag, Cuenca, Lipa, Balete and Mataas na Kahoy.
Permanent settlement in the island is prohibited by the Philippine Institute of Volcanology and Seismology or PHIVOLCS, declaring the whole Volcano Island as a high-risk area and a Permanent Danger Zone (PDZ). Despite the warnings, poor families have settled on the island, risking their lives, earning a living by fishing and farming crops from the rich volcanic soil.
Recent activity
Although the volcano has been quiet since 1977, it has shown signs of unrest since 1991, with strong seismic activity and ground fracturing events, as well as the formation of small mud pots and mud geysers on parts of the island. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) regularly issues notices and warnings about current activity at Taal, including ongoing seismic unrest.
2011
From April 9 to July 5, Alert Level on Taal Volcano was raised from 1 to 2 for eleven weeks because of increased seismicity on Volcano Island. Frequency peaked to about 115 tremors on May 30 with maximum intensity at IV, accompanied by rumbling sounds. Magma was intruding towards the surface, as indicated by continuing high rates of CO2 emissions in the Main Crater Lake and sustained seismic activity. Field measurements on 24 May 2011 showed lake temperatures slightly increased, pH values slightly more acidic and water levels 4 cm higher. A ground deformation survey conducted around the Volcano Island 26 April - 3 May 2011 showed that the volcano edifice inflated slightly relative to the 05-11 April 2011 survey.
2010
8 June. PHIVOLCS raised the volcano status to Alert Level 2 (scale is 0-5, 0 referring to No Alert status), which indicates the volcano is undergoing magmatic intrusion which could eventually lead to an eruption. PHIVOLCS reminds the general public that the Main Crater remains off-limits because hazardous steam-driven explosions may occur, along with the possible build-up of toxic gases. Areas with hot ground and steam emission such as portions of the Daang Kastila Trail are considered hazardous.
11--24 May. Crater lake temperature increased by 2-3°C. The composition of Main Crater Lake water has shown above normal values of Mg/Cl, SO4/Cl and Total Dissolved Solids. There has been ground steaming accompanied by hissing sounds on the northern and northeast sides of the main crater.
26 April. Volcanic seismicity had increased.