Report on Fuego (Guatemala) — 29 July-4 August 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
29 July-4 August 2020
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2020. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 29 July-4 August 2020. 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 at 2050 on 29 July lahars descended the Las Lajas and El Jute drainages on Fuego’s SE flanks. There were 6-13 explosions per hour recorded during 29 July-4 August, generating ash plumes as high as 1.1 km above the crater rim that generally drifted 15-20 km NW, W, and SW. Shock waves rattled buildings within a 20-km radius, particularly in areas on the S flank. Incandescent material ejected 100-350 m high caused avalanches of blocks in the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Las Lajas, and Honda drainages; avalanches sometimes reached vegetated areas. Ashfall was reported in several areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Finca Palo Verde, San Pedro Yepocapa (8 km NW), and Sangre de Cristo (8 km WSW).
Geological Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. 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 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.