Report on Fuego (Guatemala) — 22 February-28 February 2017
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 22 February-28 February 2017
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2017. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 22 February-28 February 2017. 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 21-22 February there were 28 explosions detected at Fuego, and ash plumes that rose as high as 1 km above the crater rim and drifted E and NE. There were 32 explosions recorded during 23-24 February; ash plumes rose 650 m and drifted S and SW. Lava fountains rose 200 m high, and generated a 200-m-long lava flow that descended the Santa Teresa (W) drainage. A second lava flow descended the Las Lajas (SE) drainage. Seismicity increased on 24 February. On 25 February explosions generated ash plumes that rose as high as 1.3 km above the crater and drifted more than 25 km NW, N, NE, and E. Ash fell in Alotenango (8 km ENE), San Vicente Pacaya, El Rodeo, El Zapote, La Reunión, and Alotenango. Lava fountains rose 300 m, and material was ejected as far away as 500 m. The lava flows continued to advance, extending 1.2 km in the Santa Teresa drainage, 1.3 km in the Las Lajas drainage, and 1.6 km in the Ceniza (SSW) drainage. Weak-to-moderate explosions during 26-27 February produced ash plumes that rose at most 750 m and drifted 8 km W and SW.
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.