LEGAZPI CITY?Magma heating up water in Bulusan Volcano is causing its unstable condition, a government volcanologist said Monday, but he could not confirm if this was a sign of an imminent eruption.
Sabit said the series of ash explosions, including Sunday?s blast, was the result of accumulated pressure from boiling materials just above the magma chamber five kilometers underneath the volcano?s edifice.
?We still cannot confirm if there is an advancing magma upward, but the current very unstable condition of Bulusan is also caused by magma which is responsible for heating up water on the surface of the crater and other sources above the magma chamber,? he said.
Experts call this activity ?hydrothermal.? Lava traces on the crater will confirm the presence of magma at the summit area, Sabit said, citing what happened in 1918 to 1919 prior to a strong eruption.
Scientists of the Philippine Institute of Volcanology and Seismology are determining Bulusan?s seismicity and ground deformation, taking ash sampling for chemical composition and surveying for sulfur dioxide and other harmful gases.
Water level is low at the Bulusan lake despite the rain showers, according to a member of the non-government organization Agap Bulusan, prompting it to wonder why it is high during summer.
It is now at least two meters below the original mark, the group said.
In Monbon village in Irosin town, Nerissa Japon, 36, said the water level had lowered by at least 12 inches. She also claimed that the free flowing faucets in the resort near them had drained.
Olive Maquiniana, 35, noted that at least two springs where villagers do their laundry had remained dry.
?We are apprehensive that this is related to the still abnormal state of Bulusan Volcano,? she added.
Classes at Gallanosa National High School in Irosin town, which is being used as an evacuation center, have not been canceled and pupils have ?coexisted? with evacuees, according to Bennie Recebido of the Philippine Information Agency in Sorsogon. Rey M. Nasol and Joey Gois, Inquirer Southern Luzon