Web Extra Monday, September 11, 2006
Mayon Volcano eruption slows
seismic events and lessened ground deformation indicate that the ongoing
eruption of Mayon Volcano, the Philippines' most active volcano, is finally
slowing down, according to a Sept. 9 bulletin from the Philippine
Institute of Volcanology and Seismology (PHIVOLCS). The slowdown follows
almost two months of volcanic unrest for the mountain, which is located
on the Philippine island of Luzon.
On July 14, Mayon started a "mild" eruption, as pieces of lava tumbled midway down the mountain's flanks, and the number of earthquakes and amount of sulfur dioxide emissions increased, according to PHIVOLCS. As a result, the institute increased the alert level to 3 (out of a possible maximum 5) implying an "increased tendency towards eruption," and advised that people stay at least 6 kilometers away from the mountain. Then, on Aug. 7, the institute raised the alert level to 4, indicating an eminent eruption, as six small events between 7:08 a.m. and 7:48 a.m. spewed ash up to only 800 meters above Mayon's summit.
large explosive eruption that some scientists expected never happened,
however, and the number of volcanic earthquakes has been dropping. Scientists
detected 31 events on Sept. 2, followed by nine events on Sept. 3 and
only two on Saturday, according to PHIVOLCS bulletins on those days. Still,
despite the slowdown, Mayon remains under an alert level 4, and areas
8 kilometers from the mountain are considered a hazardous danger zone.
Mayon Volcano is located on the
Philippine island of Luzon, at the junction of two tectonic plates. Mayon
is the most active of the region's major volcanoes.
Beyond the hazardous zone, about 30,000 people remain in evacuation centers,
where they have been living for more than a month, according to a Sept.
8 Agence France-Presse report. So far, there is no
word as to when evacuees can return home, the report says.