Report on Fuego (Guatemala) — 9 December-15 December 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 9 December-15 December 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 9 December-15 December 2015. Smithsonian Institution and US Geological Survey.
14.473°N, 90.88°W; summit elev. 3763 m
All times are local (unless otherwise noted)
INSIVUMEH reported that during 10-12 December explosions at Fuego generated ash plumes that rose 450-950 m above the crater and drifted as far as 12 km W and SW. Shock waves from the explosions vibrated nearby homes. Incandescent material was ejected 200 m high, landed on the flanks, and then formed small avalanches in the Santa Teresa (SW), Taniluyá (SW), and Las Lajas (SE) drainages. Block avalanches reached vegetated areas during 11-12 December. Activity increased during the night of 14-15 December, characterized by an increased number of explosions (4-6 per hour). Ash plumes rose almost 1 km high and drifted 10-15 km NE, E, and SE. Two 800-m-long lava flows were active in the Trinidad (S) and Santa Teresa drainages.
Geologic Background. Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3763-m-high Fuego and its twin volcano to the north, Acatenango. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at Acatenango. In contrast to the mostly andesitic Acatenango, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows.