Report on Fuego (Guatemala) — 8 August-14 August 2018
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 8 August-14 August 2018
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2018. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 8 August-14 August 2018. 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 on 9 August heavy rain triggered lahars that traveled down the Seca drainage on Fuego’s W flank and the Mineral drainage, carrying tree trunks and blocks as large a 2 m in diameter. During 12-14 August weak-to-moderate explosions generated ash plumes that rose almost as high as 1 km above the summit and drifted W and SW. Incandescent material was ejected 150 m high, and avalanches of blocks descended the Cenizas (SSW), Las Lajas (SE), and Santa Teresa (W) drainages. Ashfall was reported in Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I (8 km SW), and finca Palo Verde.
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.