Mayon Volcano Bulletin

21 September 2006

8:00 AM

Mayon Volcano’s (13.2576’N, 123.6856’E) seismic network detected 3 volcanic earthquakes, 20 tremor episodes and continuous occurrence of low frequency harmonic tremor during the past 24 hour observation period. The Sulfur Dioxide emission rate of the volcanic plume was measured at 2,200 tonnes per day (t/d) compared to 1,200 t/d recorded the other day.  Intermittent discharge and tumbling down of incandescent lava fragments from the summit characterized on-going surface activity.  Steaming was moderate with white plumes drifting east northeast.

Alert Level 3 remains hoisted over Mayon Volcano, which means that Mayon is still at a high level of unrest. Ash explosions and secondary pyroclastic flows arising from the collapse of lava fragments may occur suddenly. PHIVOLCS reminds the public that the following zones should remain off-limits: the Extended Danger Zone, which is the area in the southeast sector up to 7 kilometers from the summit crater, and for all other areas around the volcano, the 6 kilometer-radius Permanent Danger Zone.