Based on web camera views, INGEOMINAS reported that on 16 October an ash plume from Nevado del Huila rose 1 km and drifted E. Ashfall and sulfur odors were reported in several surrounding areas. Later that day, seismicity increased, prompting INGEOMINAS to raise the Alert Level to II (Orange; "probable eruption in term of days or weeks").

Geological Summary. Nevado del Huila, the highest peak in the Colombian Andes, is an elongated N-S-trending volcanic chain mantled by a glacier icecap. The andesitic-dacitic volcano was constructed within a 10-km-wide caldera. Volcanism at Nevado del Huila has produced six volcanic cones whose ages in general migrated from south to north. The high point of the complex is Pico Central. Two glacier-free lava domes lie at the southern end of the volcanic complex. The first historical activity was an explosive eruption in the mid-16th century. Long-term, persistent steam columns had risen from Pico Central prior to the next eruption in 2007, when explosive activity was accompanied by damaging mudflows.

Source: Servicio Geológico Colombiano (SGC)