According to the Washington VAAC, INGEOMINAS reported a seismic event from Nevado del Huila on 11 November consistent with a potential ash emission. A possible ash plume detected in satellite imagery drifted 25 km WSW. A subsequent notice stated that seismicity returned to background levels and the plume was no longer visible. INGEOMINAS reported that during 10-16 November whitish-colored gas plumes seen through the Tafxnú and Maravillas (12 km SE) web cameras rose 2 km above the crater. The Alert Level had been lowered to III (Yellow; "changes in the behavior of volcanic activity") on 12 October, and remained at that level during the reporting period.

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.

Sources: Washington Volcanic Ash Advisory Center (VAAC), Servicio Geológico Colombiano (SGC)