During 15-21 April, INGEOMINAS reported that gas plumes from Nevado del Huila's lava dome, viewed through the web camera, rose to a maximum altitude of 6.9 km (22,600 ft) a.s.l. and drifted W. On 19 April, intense degassing observed during an overflight produced whitish and bluish plumes. Thermal anomalies were detected on the N and S parts of the dome. The Alert Level was at Yellow.

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)