By Joseph John J. Perez
LEGAZPI CITY (21-May-2013) – The Philippine Institute of Volcanology and Seismology (Phivolcs) will be boosting their monitoring instruments in the vicinity of Mayon Volcano to improve detection of volcanic activities.
“We already have several instruments at the (Mayon Volcano’s) base, but there is still a need to improve visualization of the geophysical and geodetical trending,” Phivolcs Resident Volcanologist Eduardo Laguerta said.
“There is not much activity inside the volcano since 2012,” Laguerta said, as he points out that the instruments are consistently generating graphical outputs, indicating that all parameters are not conclusive of any danger.
“Based on the geophysical activities of Mayon, the magma movements are normal,” Laguerta said.
“The gas output of Mayon is maintained within the normal values with its sulphur dioxide emissions ranging in normal production,” Laguerta said. “What happened on May 7 is normal,” he added.
Mayon, one of the world’s most active volcanoes had a phreatic explosion last May 7 that killed five mountaineers and injured eight others. A phreatic explosion happens if the hot rocks inside a volcano come in contact with a water system that will cause a steam pushing up to the crater and creating an ash cloud.
Reacting on a possibility of forthcoming major eruption next year based on an experience in the year 2008 that minor eruptions preceded a major eruption in 2009, Laguerta said, “Maybe not, maybe yes.”
“Small eruptions are hard to determine, alert levels are (used) for major eruptions,” Laguerta said. The permanent danger zone however must be observed strictly at all times, Laguerta added.
Mayon Volcano was in alert level zero when it spewed ash early last week.
“The six-kilometer permanent danger zone is based on Phivolcs’ geological study, Mayon’s morphology and its history of past eruptions,” Laguerta said.
“With its 2.5 kilometers height and 40 degrees slope, its steepness is prone to falling accidents and earthquakes will topple down rocks from its summit,” Laguerta said.
“The aviation protocol must be strictly imposed,” said Laguerta. “Aircrafts must not pass through an ash cloud for it may cause plane crash”.
The augmentation of instruments is not only necessary for present utilization but for future researches. “All these data can be used in the future, and for future scientists for their studies,” Laguerta said.