Report on Fuego (Guatemala) — 4 February-10 February 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 4 February-10 February 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, 4 February-10 February 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 5-6 February explosions at Fuego ejected incandescent tephra 150 m above the crater, causing avalanches in the Taniluya (SSW), Ceniza, and Trinidad (S) drainages. Shock waves rattled nearby structures. Ash plumes rose 550 m above the crater and drifted 11-12 km S and SW. A Strombolian eruption commenced on 7 February; plumes with water vapor and ash rose as high as 1.3 km and drifted 20 km NW. Pyroclastic flows descended multiple drainages. CONRED reported that ash fell in Guatemala City (about 35 km ENE) and flights were diverted to El Salvador. On 8 February, although activity had decreased, the seismic network detected 30 explosions per minute. Explosions sounded like locomotives and generated shock waves detected in areas 15 km S and SW. Lava flows were at most 2 km long in the El Jute (SE) and Trinidad (S) drainages, reaching vegetated areas and causing fires. In a special notice INSIVUMEH stated that activity levels had returned to normal; weak to moderate explosions produced ash plumes that rose 550 m and drifted 8-10 km NW. Morphological changes had occurred on the S flank from pyroclastic flows. Avalanches from the lava flows also descended the southern flanks. Explosions during 9-10 February generated ash plumes that rose 800 m and drifted 11-12 km S 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.