Philippines - Mayon Volcano Bulletin 7:00 PM, 09 Jan 2001

Originally published
A possible resurgence of activity is evident from recent observations on Mayon. Reports by the Ligñon Hill Observatory in Legazpi City disclosed an apparently growing lava dome, which is also emitting voluminous volcanic gases from the summit crater. Significantly increased earthquake occurrences have also occurred this past week and these events are likely related to ascent of magma. Such ascent is also indicated by slight ground tilt that has coincided with appearance of the lava dome, and the sustained gas outputs visible during cloud breaks. Due to near-constant cloud cover, however, no crater glow has been observed yet but the major monitored parameters strongly suggest that activity is rapidly progressing beyond the usual background or quiet conditions.
Because of the reactivation of the volcano which may eventually lead to a lava flow-producing or pyroclastic flow-producing eruption, PHIVOLCS is now hoisting Alert Level 2, meaning increased and sustained volcanic unrest. No time frame or precise eruption prediction can be given yet because of the short observation period and the lack of good visibility of the summit area. As a precaution against hazards from sudden explosions, however, PHIVOLCS advises the public to stay away from the six (6) kilometer radius Permanent Danger Zone (PDZ) and to avoid major river channels that originate from the volcano. In addition, all treks within the prescribed PDZ, should be postponed until the alert has been lowered to the appropriate level.

In the meantime, additional volcano monitoring teams are now being sent on-site to further evaluate the unrest and any significant developments shall be relayed to all concerned.

European Volcanological SOCIETY
C.P.1 - 1211 Geneva 17
Fax : 41.22.759.21.05