INSIVUMEH reported that explosions from Fuego produced white and gray plumes that rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted SW on 12 January. Incandescent material was propelled up to 75 m above the summit and incandescent blocks rolled W towards the Taniluyá and Santa Teresa ravines on 12 January and S towards the Ceniza ravine on 12 and 16 January. Based on information from the Tegucigalpa MWO and satellite imagery, the Washington VAAC reported that a faint plume was seen on 12 January drifting W.

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.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)