Summit crater glow was observed between 2002 and 2125 on 6 November from COMVOL observation stations. Glow was continuous and deep red for the first 3 minutes, then became intermittent and yellowish in color. The next day, steam emission, under increased pressure, occasionally varied in volume and intermittently changed from the normal white color to brown. Several new steam vents had formed outside the crater, on the upper flank. Glow was again observed during the night of 8-9 November and volcanic tremor was recorded.

Reference. Moore, J.G., and Melson, W.G., 1969, Nuées ardentes of the 1968 eruption of Mayon volcano, Philippines: BV, v. 33, no. 2, p. 600-620.

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 periods of andesitic lava flows. Eruptions occur predominately from the central conduit and have also produced lava flows that travel far down the flanks. Pyroclastic density currents 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.

Information Contacts: G. Andal, COMVOL, Quezon City.