The Instituto Nacional de Sismología, Vulcanologia, Meteorologia e Hidrología (INSIVUMEH) reported that eruptive activity at Fuego continued during 12-18 November. Daily Strombolian explosions recorded by the seismic network, at rates of 4-12 per hour, generated gas-and-ash plumes that rose as high as 1.1 km above the summit and drifted as far as 40 km W and SW. Occasional rumbling sounds, shock waves, and/or sounds associated with gas emissions were reported; the shock waves rattled buildings and structures near the volcano during 13-14 November. Explosions ejected incandescent material 200 m above the summit, sometimes showering the upper flanks with incandescent material. Daily incandescent block avalanches descended the flanks, including the Las Lajas (SE), Seca (W), Taniluya (SSW), Trinidad (SSW), Santa Teresa (W), El Jute (ESE), Honda, and Ceniza (SSW) drainages, occasionally reaching vegetated areas. Ashfall was reported in areas downwind almost daily including Panimache (8 km SW), Sangre de Cristo, Finca Palo Verde, El Porvenir (10 km S), Morelia (10 km SW), Santa Sofia (12 km SW), and Yepocapa. On 16 November lahars descended the Mineral and Seca drainages carrying sediment, tree branches, trunks, and blocks as large as 3 m in diameter.

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 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)