Report on Agung (Indonesia) — 17 April-23 April 2019
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 17 April-23 April 2019
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2019. Report on Agung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 17 April-23 April 2019. Smithsonian Institution and US Geological Survey.
8.343°S, 115.508°E; summit elev. 2997 m
All times are local (unless otherwise noted)
PVMBG reported two explosive eruptions at Agung on 21 April. The first was recorded at 0321 and produced a dense gray ash plume that rose 2 km above the crater rim and drifted W and S. Ashfall was reported in areas downwind including Besakih (7 km SW), Rendang (12 km NW), Klungkung (~40 km S), Gianyar (20 km WSW), Bangli (17 km WNW), Tabanan (51 km WSW), and the International Gusti Ngurah Rai (IGNR) airport (60 km SW) in Denpasar. The second event was recorded at 1856 and generated a dense ash plume that rose 3 km and drifted S. Minor ashfall was reported in Besakih, Rendang, Sebudi (6 km SW), and Selat (12 km SSW). The eruptions were accompanied by a boom heard at both the Rendang and Batulompeh observation posts. Ejected incandescent material from the two events fell on the flanks in all directions within a radius of 4 km. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.
Geologic Background. Symmetrical Agung stratovolcano, Bali's highest and most sacred mountain, towers over the eastern end of the island. The volcano, whose name means "Paramount," rises above the SE caldera rim of neighboring Batur volcano, and the northern and southern flanks extend to the coast. The summit area extends 1.5 km E-W, with the high point on the W and a steep-walled 800-m-wide crater on the E. The Pawon cone is located low on the SE flank. Only a few eruptions dating back to the early 19th century have been recorded in historical time. The 1963-64 eruption, one of the largest in the 20th century, produced voluminous ashfall along with devastating pyroclastic flows and lahars that caused extensive damage and many fatalities.