Report on Fuego (Guatemala) — 22 September-28 September 2004
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 22 September-28 September 2004
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2004. Report on Fuego (Guatemala). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 22 September-28 September 2004. Smithsonian Institution and US Geological Survey.
14.473°N, 90.88°W; summit elev. 3763 m
All times are local (unless otherwise noted)
Weak explosions at Fuego on 21 September produced white plumes to ~200 m above the volcano. During 25-26 September, several moderate explosions emitted incandescent lava bombs to heights of ~150 m and plumes to 600-900 m above the volcano. The explosions were accompanied by avalanches of volcanic material that traveled W to the head of Santa Teresa Ravine.
Geologic Background. 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.