Report on Fuego (Guatemala) — 31 January-6 February 2018
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 31 January-6 February 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, 31 January-6 February 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 the first Strombolian eruption at Fuego in 2018 began on 31 January, after a thermal anomaly was detected in satellite images the day before. Explosions produced ash plumes that rose 1.5 km above the crater and drifted 20 km SW. Lava fountains rose 300-500 m, and fed lava flows that traveled 800 m W in the Seca (Santa Teresa) drainage and 600 m in Las Lajas (SE) and Honda (E) drainages. On 1 February the eruption style changed to Vulcanian. Pyroclastic flows mainly descended the Seca, Trinidad (S), Las Lajas, and Honda drainages. Ash plumes from explosions rose 3.2 km and drifted more than 60 km NE, SW, and W. Ashfall was recorded in areas downwind including Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I and II (8 km SW), El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), Finca Palo Verde, San Pedro Yepocapa (8 km NW), Ciudad Vieja (13.5 km NE), Antigua Guatemala (18 km NE), and W and SW Ciudad de Guatemala. CONRED reported that 2,880 people were evacuated. At 1630 INSIVUMEH noted that the Strombolian-Vulcanian eruption phase had finished, 20 hours after it had begun. Explosions continued, generating ash plumes that rose just under 1 km and drifted 15 km SW.
On 2 February there were 3-5 weak explosion recorded per hour, with ash plumes rising 750 m and drifting 5-8 km W, SW, and S. Shock waves and rumbling were noted, and the lava flows remained visible. During 4-5 February ash plumes from explosions (about 5 per hour) produced ash plumes that rose 700 m and drifted W and SW. Incandescent material was ejected 200 m above the crater, causing weak avalanches of material around the crater area and in some 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.