Report on Mayon (Philippines) — 20 August-26 August 2014
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 20 August-26 August 2014
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2014. Report on Mayon (Philippines) (Sennert, S, ed.). Weekly Volcanic Activity Report, 20 August-26 August 2014. Smithsonian Institution and US Geological Survey.
13.257°N, 123.685°E; summit elev. 2462 m
All times are local (unless otherwise noted)
During 20-26 August PHIVOLCS reported no incandescence at Mayon, despite the emergence of a summit dome, slight ground deformation, and increased volcanic gas emission. On most days seismic instruments recorded a few rock falls and sparse earthquakes. During 20-25 August observers noted moderate emission of white steam plumes that drifted SW, WSW, NE, ENE, and SSW. The Alert Level remained at 2 (on a scale of 0-5).
Geological Summary. Symmetrical Mayon, which rises above the Albay Gulf NW of Legazpi City, is the most active volcano of the Philippines. The steep upper slopes are capped by a small summit crater. Recorded eruptions since 1616 CE 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 damaged populated lowland areas. A violent eruption in 1814 killed more than 1,200 people and devastated several towns.