Report on Fuego (Guatemala) — 28 September-4 October 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 28 September-4 October 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 28 September-4 October 2016. Smithsonian Institution and US Geological Survey.
14.473°N, 90.88°W; summit elev. 3763 m
All times are local (unless otherwise noted)
Based on INSIVUMEH reports, CONRED stated that beginning at 0730 on 27 September loud explosions at Fuego generated ash plumes that rose 1 km above the crater rim and drifted more than 15 km W and SW. After about 36 hours of elevated activity, the 13th Strombolian episode in 2016, Fuego returned to more normal levels. On 28 September there were 4-6 explosions per hour recorded, producing ash plumes that rose 550-650 m and drifted 8-12 km W and SW. Lava flows in the Las Lajas (SE) and Santa Teresa (W) drainages had stalled. Explosions during 30 September-1 October and 3-4 October generated ash plumes that rose as high as 1.1 km and drifted 7-13 km W, SW, and S. During 3-4 October explosions produced shock waves and ashfall in Morelia (10 km SW). Incandescent material was ejected 300 m high, and block avalanches reached vegetated areas.
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.