PHIVOLCS reported that during 13-19 March white steam plumes periodically emitted from Mayon drifted mainly W and SW, and crater incandescence was visible nightly. Three phreatic events, recorded at 1510, 1518, and 1534 on 12 March, generated light-brown-to-grayish ash plumes that rose 500-1,000 m above the crater rim and drifted SW. Six phreatic events on 13 March, recorded at 0906, 0939, 0946, 0955, 1000, and 1059, produced ash plumes that rose 200-700 m and drifted W. A phreatic event at 1855 on 14 March generated an ash plume that rose 500 m and drifted SW. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.

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.

Source: Philippine Institute of Volcanology and Seismology (PHIVOLCS)