On 21 July Servicio Geolï¿½gico Colombiano?s (SGC) Observatorio Vulcanolï¿½gico y Sismolï¿½gico de Manizales reported that seismicity at Nevado del Ruiz was generally characterized by higher number of earthquakes that had larger magnitudes than the previous week. Gas-and-steam emissions were sometimes visible in webcam images rising as high as 1.1 km above the summit and drifting WNW and WSW; these emissions sometimes contained ash. Episodes of drumbeat seismicity were recorded during 13-14 and 17 July, indicating ascent or growth of a lava dome in Arenas Crater. The Alert Level remained at 3 (Yellow; the second lowest level on a four-color scale).
Source: Servicio Geolï¿½gico Colombiano (SGC)
Syndicated from Smithsonian / USGS Weekly Volcanic Activity Report