INSIVUMEH reported that on 4 July there were rumbling noises from Fuego and the seismic network detected multiple explosions. A lava flow traveled 100 m W towards the Santa Teresa ravine. A lahar carrying blocks descended the Ceniza ravine to the SW. On 7 and 8 July, explosions produced ash plumes that rose to altitudes of 4-4.5 km (13,100-14,800 ft) a.s.l. and drifted S, SE, and SW. Incandescence at the summit was observed and constant avalanches of blocks from lava-flow fronts descended the W flank.

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)