‘Full moon to trigger Mayon eruption’

LEGAZPI CITY — Volcanologists said here yesterday that tonight’s full moon may trigger Mt. Mayon’s explosion since the volcano started its lava flow on July 12, also during a full moon.

"The ‘earth tide’ phenomenon could be considered as an essential possibility in triggering an eruption for a volcano that is ready to erupt," Philippine Institute of Volcanology and Seismology (Phivolcs) director Renato Solidum told The STAR.

Earth tide, just like the high tide phenomenon, happens whenever the earth exerts the strongest gravitational pull on the moon since the two heavenly bodies are nearest each other during this period, Solidum said.

"So if the ocean’s tide rises its level during full moon because of gravitational pull, it may also affect materials inside the volcano during this event," he said.

Solidum said while the earth tide phenomenon is not yet 100 percent reliable in predicting an eruption, its scientific explanation does not discount a possibility that it might trigger the eruption of a volcano that is showing abnormal behaviors.

"They found it both logical and scientific to believe that the earth tide phenomenon could affect the eruption of volcanoes which are in abnormal conditions," he said.

Solidum said all of the 2,462-meter volcano’s parameters monitored by Phivolcs experts "give us no other way to interpret but that Mayon is leading towards a big eruption."

Three more explosions were observed the other night at 10:36 p.m., 10:46 p.m., and 10:49 p.m. and these were accompanied by "incandescent ejections of lava fragments and significant brightening of the summit area as hot gas and steam were released," Phivolcs reported.

Phivolcs resident volcanologist Ed Laguerta said "these explosions signify that the volcano is going to erupt soon," adding that some 25 million to 27 million cubic meters of lava have already been extruded by the volcano since July 15.

"What is unique about this pattern of eruption is that this is the first time the volcano has shown a longer period of lava extrusion which runs now to three weeks," he said.

Laguerta said the probability of a major eruption is high compared to Mayon’s eruption in 1978, which was mainly characterized by lava flows.

Low-frequency volcanic quakes, indicating an ongoing magma ascent towards the surface, were detected 109 times while the emission of sulfur dioxide again rose to 12,745 tons yesterday after a precipitous drop.

The six-kilometer danger zone for barangays facing Mayon’s southeast sector has been expanded to eight kilometers. It is in this area where the Bonga gully, the largest ditch on the volcano’s slopes, is located.

A seven-kilometer danger zone is in effect in other areas surrounding Mayon. Phivolcs said residents in areas outside of the expanded danger zone are advised to be alert for updates regarding their evacuation.

Laguerta said the lava column that began streaming out of the crater more than three weeks ago was now just two kilometers from inhabited areas. He said it was contained within two channels and was no threat to people, although it was burning coconut plantations.

He said the greatest danger would be from so-called "pyroclastic flows" or the superheated ash and other volcanic material that spurt from the crater and flow down the mountain’s flanks at great speed.

Laguerta said these flows killed 77 people, mainly farmers, in Mayon’s last deadly eruption in 1993.

No casualties

President Arroyo expressed confidence that there would be no casualties should Mayon erupt because government agencies have prepared for this event.

In a statement, the President also assured that authorities have enough resources to shoulder evacuees’ basic needs and "that people will not be kept from their homes longer than is necessary."

"With the well-organized and effective handling of this crisis, we are confident of achieving a zero-casualty goal in this looming natural disaster," she said. "Our solidarity and cooperation is imperative in keeping our families safe and sound."

Mrs. Arroyo called on local residents "not to flirt with danger by going back to the declared danger zones and instead heed the advice of experts and disaster officials to stay out of harm’s way."

She commended local officials, concerned national government agencies, the private sector and affected communities for the successful evacuation of families residing on Mayon’s slopes.

Phivolcs raised Mayon’s alert level to four the other day after a series of ash ejections were observed Monday morning, which prompted disaster control officials in Albay to start the evacuation of some 40,000 people residing within six to eight kilometers from the crater of the volcano.

Data from the Office of Civil Defense (OCD) in Bicol showed that evacuees increased to 4,213 families or 20,656 persons yesterday morning in the 14 evacuation centers and two resettlement sites in the cities of Tabaco, Ligao and Legazpi and the municipalities of Malilipot, Sto. Domingo, Daraga, Camalig and Guinobatan.

The evacuees were transported to the evacuation centers by the police, military and local government unit vehicles from the affected villages of Bonga, Buyuan, Matanag and Mabinit here; Fidel Surtida, Sta. Misericordia, San Fernando, San Isidro and Lidong in Sto. Domingo town; Matnog, Bañadero, Miisi and Salvacion in Daraga; Upper Quirangay, Sua-Tubran and Upper Cabangan in Camalig.

Some evacuees came from Baligang in Ligao City, Calbayog in Malilipot and Maninila in Guinobatan, Albay’s Provincial Disaster Management Office (PDMO) reported.

Cedric Daep said the evacuation of residents who chose to remain within the extended eight-kilometer danger zone continued as relief goods and medicines had already started to pour in to the evacuation camps.

Daep said that they will try to follow the recommendation of health officials to limit the number of occupants to 20 persons per room in the evacuation camps to avoid overcrowding and outbreak of illnesses.

Legazpi Mayor Noel Rosal said he has requested the Department of Education to open padlocked classrooms to accommodate the increasing number of evacuees.

Braving danger

Despite the mandatory evacuations, many villagers stayed put on farms around Mayon to tend their crops and livestock while guarding their homes and belongings.

In Matanag, a farming village of about 1,400 people well within the danger zone, life looked almost normal. About 600 residents left on Monday, but many more chose to stay behind. An Army truck, a disco beat blaring from its radio, sat at the village entrance, ready to assist in a quick escape.

Soldiers, however, dropped a coconut tree across the road to Matanag, blocking any incoming traffic.

Some of those evacuated still make periodic trips to Matanag to pick up belongings and check on their homes. Soldiers said they could not force them to leave.

Second Lt. Alan Matres, head of an Army team securing Matanag, said the women and children had left and that mainly men had stayed behind to guard their homes and farms.

"They are the last priority," he said.

Officials are hoping Mayon, which has erupted at least 47 times since records began being kept in 1616, would go off quietly. An explosive eruption would complicate evacuation efforts, although Albay has developed one of the country’s most efficient disaster response systems, Gov. Fernando Gonzalez said.

He hopes the evacuation will be completed Tuesday.

Mayon is one of the Philippines’ 22 active volcanoes. Its most violent eruption, in 1814, killed more than 1,200 people and buried the entire town of Cagsawa in mud. — With Sheila Crisostomo, Paolo Romero, James Mananghaya, AP, AFP