Based on web camera views, INGEOMINAS reported that during 23-29 December a continuous white plume from Nevado del Huila rose 1 km. The output of sulfur dioxide was less than during the previous months of October and November. Seismicity and the rate of lava extrusion had also decreased during the previous weeks. On 5 January, INGEOMINAS lowered the Alert Level to III (Yellow; "changes in the behavior of volcanic activity").

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)