INSIVUMEH reported that during 11-12 October explosions at Fuego produced ash plumes that rose 1,650-1,950 m above the crater and drifted 10-12 km WSW. Explosions ejected incandescent tephra 150 m above the crater and generated shock waves that rattled structures within a 13-km radius. Ashfall was reported in Panimaché (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), San Pedro, and Yepocapa (8 km NW). During 12-14 October explosions produced ash plumes that rose 500-800 m above the crater and drifted 7-12 km S and SW. Incandescent pulses rose 100-150 m above the crater. During 13-14 explosions rattled structures in Morelia, Panimache, and Sangre de Cristo, and incandescent blocks from the crater were observed at night.

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)