INGEOMINAS reported that an ash-and-gas plume from Galeras rose to an altitude of 4.9 km (16,100 ft) a.s.l. and drifted NW on 31 December. The emission was associated with an episode of spasmodic tremor. Another plume rose to an altitude of 4.5 km (14,800 ft) a.s.l. and drifted S.
Source: Instituto Colombiano de Geología y Minería – “Report provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”