INSIVUMEH reported that during 29-30 August lava flows from Fuego traveled 250 m down the Taniluyá drainage (SW), generating block avalanches that produced gray plumes and reached vegetated areas.

Seismicity increased on 3 September. During 3-4 September constant Strombolian explosions generated ash plumes that rose 900 m above the crater and drifted 8 km S and SW. The eruption was heard in areas 10 km away and vibrated structures in Panimaché (8 km SW), Morelia (8 km SW), and Santa Sofia (12 km SE). Lava was ejected 100 m high and spilled over the crater rim. Lava flows traveled 3 km down the Taniluyá and the Ceniza (SSW) drainages, producing block avalanches that again reached vegetated areas. A third lava flow descended the Las Lajas drainage (SE). Pyroclastic flows traveled SE. Ash plumes drifted 10-12 km S and SW, and produced ashfall in Panimaché, Morelia, Santa Lucía, Cotzumalguapa, Tierra Linda, and Popoya.

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)