Philippines - Mayon Volcano Bulletin 25 Jun 2001

News and Press Release
Originally published
After declaring Alert Level 5 (Hazardous Eruption in Progress) at 1:00 P.M. yesterday, major eruptions began at 2:44 P.M. The eruptions were characterized by strong explosions, multiple pyroclastic flows around the volcano and lavas that flowed into gullies on the southeast flanks. The pyroclastic flows passed through the major river channels fronting Basud, Buyuan, Mabinit/Bonga, Miisi, Anoling, Maninila, Nabonton and Buang, all within the 6-kilometer radius Permanent Danger Zone (PDZ). The main eruption cloud discharged from the crater rose to about 10 kilometers altitude and moderate to heavy ash were dispersed mainly to the Northeast in the vicinity of Malilipot by prevailing winds. Residents in Tabaco farther Northeast also experienced light ashfalls.
Although lava flows and dilute ash clouds dominated subsequent activity from 3:41 P.M. until activity waned early this morning, PHIVOLCS expects similar explosive activity in the following days. The general public is therefore reminded that Mayon is still at Alert Level 5 and that the previously delineated danger zones should be strictly off-limits. These areas are the 6-kilometer PDZ and the Extended Danger Zone (EDZ) to the southeast facing Mabinit, Bonga, Matanag and Buyuan Gullies. These areas are most susceptible to hazards by pyroclastic flows, volcanic blasts and ground surges. In the event of large explosive eruptions, more areas may be declared as danger zones. Because of the changing wind drifts, and ash derived from pyroclastic deposits, areas just beyond the danger zones should expect ashfall and prepare accordingly. Due to rain clouds that persist over the volcano, PHIVOLCS also cautions the public to avoid venturing near the river channels around Mayon because hot and life-threatening debris flows may occur with little warning.

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