Mayon Volcano Bulletin

07 September 2006

8:00 AM

For the past 24 hours, Mayon Volcano’s (13.2576⁰N, 123.6856⁰E) seismic network detected ten (10) volcanic earthquakes and 315 tremor episodes. Ground deformation measurements showed general deflation of the volcanic edifice. This signifies a slowdown in magma ascent which may also be indicated by apparent decrease in extrusion of lava fragments observed last night.

Steaming activity at the summit crater was most of the time moderate and drifted to the west and west-southwest.

In summary, seismic, ground deformation and other observed parameters indicate a further decline in activity. However, the probability of ash explosions and lava dome collapse remains high. Hence, Alert Level 4 remains hoisted over the volcano, which means that the 8-kilometer radius Extended Danger Zone (EDZ) over the southeast should be off-limits. For other areas around the volcano, the presently enforced EDZ is 7 kilometers from the summit. PHIVOLCS is continuously assessing activity and if downward trends are evident in the coming days, then the appropriate recommendation for lowering the alert status shall be made.