Mayon Volcano Bulletin

18 September 2006

8:00 AM

A total of two (2) volcanic earthquakes were recorded at Mayon Volcano (13.2576’N, 123.6856’E) during the past 24-hour observation period. In addition, the seismic network commenced recording continuous occurrence of low frequency harmonic tremor with average trace double amplitude of 4.0 mm since 5:28 AM yesterday. Fifty-seven (57) tremor episodes relating to the extrusion of lava from the summit and rolling and tumbling of detaching lava blocks from the lava deposits at the upper slope were also detected. The Sulfur Dioxide emission rate was measured at 1,500 tonnes per day (t/d) reflecting a decrease from 1,800 t/d taken the other day. Steaming from the crater was moderate with white plume reaching heights of up to 300 m before drifting to the northeast.

Alert Level 3 remains in effect over Mayon Volcano which means that the new Extended Danger Zone (EDZ) of 7 kilometers from the summit crater covering the southeast sector and the normal 6 kilometer-radius Permanent Danger Zone (PDZ) for all other areas around the volcano should remain off-limits.