Report on Mayon (Philippines) — 1 December-7 December 2004
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 December-7 December 2004
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2004. Report on Mayon (Philippines). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 1 December-7 December 2004. Smithsonian Institution and US Geological Survey.
13.257°N, 123.685°E; summit elev. 2462 m
All times are local (unless otherwise noted)
According to a news report, strong rains brought by typhoon Yoyong in the Philippines caused lahars to flow down the stream channels of Mayon, particularly in the Padang settlement, and Legazpi City (~14 km SE of the volcano's summit). The Provincial Disaster Management Officer stated that the lahars would not cause damage to homes or rice fields, and that villagers residing near the volcano were not asked to evacuate.
Geologic Background. Beautifully symmetrical Mayon, which rises above the Albay Gulf NW of Legazpi City, is the Philippines' most active volcano. The structurally simple edifice has steep upper slopes averaging 35-40 degrees that are capped by a small summit crater. Historical eruptions date back to 1616 and range from Strombolian to basaltic Plinian, with cyclical activity beginning with basaltic eruptions, followed by longer term andesitic lava flows. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic flows and mudflows have commonly swept down many of the approximately 40 ravines that radiate from the summit and have often devastated populated lowland areas. A violent eruption in 1814 killed more than 1,200 people and devastated several towns.
Source: ABS-CBN News