Friday, September 19, 2014

Mario' spares Albay but Mayon's threat remains
By Nancy I. Mediavillo

LEGAZPI CITY, Sept. 19 (PNA) – The highly religious and ever-ready Albayanos have been saved from the threat earlier posed by Typhoon “Mario” that could have worsened the present abnormal behavior of the Mayon Volcano, which is on Alert Level 3 status.

This, after Mario veered away towards northern Luzon, leaving a fine but windy weather in Albay as Mayon showed a temporary decrease in its abnormal activities.

With the presence of parameters that could lead to an eruption, the disastrous impact of an impending Mayon’s fury could have been worsened by rains dumped by Mario had it hit Albay province.

Earlier, Albayanos expressed fear over the threat of Mario hitting the province, which might have caused lahar flows.

Local authorities, however, allayed this fear of lahar flows endangering lives because the residents living within the six-kilometer-radius permanent danger zone and the 6-8-km-radius extended danger zone at the southeast quadrant have been immediately moved to safety in various evacuation centers, fully allotted with provisions that they need.

Alex Baloloy of the Philippine Institute of Volcanology and Seismology said the occurrence of lahar flows is a remote possibility since there are no new deposits of volcanic materials along the slopes of Mayon.

Baloloy said that what came from the volcano’s crater are big rocks from the lava dome.

He said that if ever there are new deposits of volcanic materials along the gullies, it would take 400 millimeters of rainfall to carry these down the slopes -- like what happened during typhoon “Reming” in 2006.

Baloloy added that the number of rockfalls and earthquakes was smaller the whole day on Thursday, compared to the past 24 hours.

But he hastened to add there is still the danger and the increasing level of abnormalities being shown by the volcano, so eveybody must still be prepared.

Phivolcs resident volcanologist Ed Laguerta stressed the importance of constant monitoring of the activities of Mayon – both physically and through the agency’s various instruments.

The monitoring should be on the geophysical, geochemical and geodetic aspects of the volcano.

Laguerta said the geophysical aspect refers to the movement of the magma inside the volcano.

The geochemical concern involves the volume of sulphur dioxide being emitted by the volcano, with the baseline being 500 metric tons per day.

When it comes to the geodetic aspect, the ground condition is being monitored as to whether there has been deformation.

“If this condition continuous, the Mayon volcano will erupt within weeks,” he added.

Once they raise the alert level to 4, he said, this means that it would only take days for them to elevate it to level 5 wherein a strong eruption is ongoing, accompanied by pyroclastic flows.

There is also a possibility that the volcano may simmer down and rest like what it did in l984, Laguerta said.

The chief volcanologist , however, cautioned on the immediate danger that would be brought by ash explosion or phreatic explosion.

Laguerta added that if there would a strong eruption, it will be magmatic with heavy pryoclastic flows like that one in the 1984 eruption.

He said it has been 13 years since the last eruption of Mayon in 2001 when it vomited pyroclastic flows.

The ones that occurred in 2006 and 2009 only caused lava flows.(PNA) CTB/FGS/NIM/CBD