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Mayon Volcano Bulletin 12 PDF Print
Friday, 25 December 2009 08:38

25 December 2009

Mayon Volcano (13.2576 N, 123.6856 E) continued to show an intense level of activity during the past 24-hour observation period. Ninety-six (96) ash explosions were observed during times of good visibility. These explosions produced light brown to grayish ash columns that reached heights of up to 2 km. One hundred twenty five (125) rumbling and booming sounds from the volcano were heard at the Lignon Hill Observatory in Legaspi City. Seismic activity remained elevated as the seismic network recorded a total of eight hundred seventy one (871) volcanic earthquakes. Ninety eight (98) rock fall events, related to detachment of lava fragments at the volcano’s upper slopes, were also detected. Three of these events were observed to have generated pyroclastic flows that moved down within 2 km from the crater. Sulfur Dioxide (SO2) emission rate was high and was measured at an average of 2,738 tonnes/day yesterday.

Alert Level 4 remains hoisted over Mayon Volcano, meaning a hazardous eruption is possible within days.  Thus, PHIVOLCS-DOST reiterates that the Extended Danger Zone (EDZ) from the summit of 8-km on the southern sector of the volcano and 7-km on the northern sector should be free from human activity.  Areas just outside of this EDZ should prepare for evacuation in the event hazardous explosive eruptions intensify.  Active river channels and those perennially identified as lahar prone in the southern sector should also be avoided especially during bad weather conditions or when there is heavy and prolonged rainfall.  PHIVOLCS–DOST is closely monitoring Mayon Volcano’s activity and any new significant development will be immediately posted to all concerned.