Report on Fuego (Guatemala) — 27 June-3 July 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 27 June-3 July 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Fuego (Guatemala). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 June-3 July 2012. 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 28-29 June activity at Fuego increased; explosions produced ash plumes that rose 500-600 m above the crater and drifted SW. Pulses of incandescence rose 200 m and tephra avalanches descended the Ceniza drainage (SSW). According to Coordinadora Nacional para la Reducción de Desastres (CONRED) on 1 July, seismicity increased and rumbling sounds were audible in areas up to 10 km away. A lava flow 700 m long was active in the Taniluya drainage on the SW flank. In a 2 July report, INSIVUMEH noted that the lava flow on the SW flank was 1,700 m long. Ash plumes rose 500 m above the crater and drifted 10 km W. The seismic network recorded continuous tremor. During 2-3 July explosions produced ash plumes that rose 400 m above the crater and drifted W. A lava flow traveled 400 m down the Taniluya drainage, and blocks from the flows reached vegetated areas.
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.