In a special bulletin, INSIVUMEH reported that an effusive period at Fuego began on 9 February, producing lava flows than descended the Ceniza drainage on the SSW flank. There were 2-9 explosions per hour recorded during 8-9 and 1-15 February, generating ash plumes that rose as high as 1.1 km above the crater rim. The ash plumes mainly drifted 10-15 km N, NE, S, SW, and W causing almost daily ashfall in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), and La Rochela. Periodic shock waves rattled structures in communities around the volcano. Block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), and Taniluyá (SW) drainages. Explosions ejected incandescent material up to 100-300 m above the summit. The effusive activity intensified by 14 February with periods of elevated activity lasting minutes to hours. Strombolian explosions increased in frequency and intensity, gas emissions increased, and incandescence from the crater was visible at night through the early morning of 15 February. Peaks in seismic RSAM data mirrored the peaks in activity. Lava flows traveled as far as 200 m down the Ceniza drainage and produced block avalanches from the flow front.

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)