INSIVUMEH reported that during 22 and 24-25 August explosions from Fuego generated ash plumes that rose 300-500 m and drifted W and NW. Degassing and rumbling sounds were also reported. Active lava flows were 300 and 500 m long in the Taniluyá (SW) and Ceniza (SSW) drainages, respectively. On 23 August lava extrusion increased. Ash plumes rose about 1 km and drifted 12 km W. Fourteen explosions during 26-27 August produced ash plumes that rose 200-500 m and drifted 8 km. Incandescent material was ejected 150 m high, and avalanches from the crater descended the flanks.

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)