Report on Fuego (Guatemala) — 19 November-25 November 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 19 November-25 November 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Fuego (Guatemala). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 19 November-25 November 2003. Smithsonian Institution and US Geological Survey.
14.473°N, 90.88°W; summit elev. 3763 m
All times are local (unless otherwise noted)
Small explosive eruptions at Fuego produced gas-and-ash plumes up to 1.2 km above the crater. During the night of 18-19 November moderate-sized avalanches were observed in the upper Santa Teresa and Trinidad ravines. Night-time incandescence at the summit was common during the week. Periods of harmonic tremor, lasting between 0.5-3 hours, were recorded on 23 November, and almost continuous harmonic tremor was recorded for a period of 21 hours on 24 November.
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.