LEGAZPI CITY , Philippines – With ground deformation surveys confirming that the surface of Mayon volcano was no longer bulging, which means the absence of more magma-related buildup, government volcanologists said they may further lower the alert level from 3 to 2 within the week.
Alex Baloloy, resident volcanologist of the Philippine Institute of Volcanology and Seismology (Phivolcs) here, said the leveling line in Buang, Tabaco City recorded a deflation of negative two millimeters, while the other one in Lidong, Sto. Domingo yielded a one-millimeter deflation.
Data before and during Mayon’s eruptions last November and December showed that the volcano’s surface was inflated by four to five millimeters.
“So based on these data, we can say that pressure buildup inside Mayon has already either stopped or gradually subsided,” Baloloy told The STAR.
He said the other abnormal parameters of the open-vent volcano were also on an overall downward trend.
In the past 24 hours, Phivolcs detected only six volcanic earthquakes, 17 rockfall-related tremors, and 850 tons of sulfur dioxide.
“All these figures are relatively lower compared to the previous ones. Therefore we can see here an overall downward trend in the volcano’s level of unrest. We might consider lowering further its alert status to two this week,” Baloloy said.
Despite this development, Phivolcs still warned of any human activities within the six-kilometer permanent danger zone and the seven-kilometer extended danger zone in the eastern section. – With Helen Flores