Friday, 18 January 2013

More aggressive eruptive activity seen at many of world’s active volcanoes

January 17, 2012  EARTH  Stromboli (Italy): The lava overflow that started on Monday and reached about 400 m elevation on the Sciara del Fuoco has stopped (for now).  Strong explosions felt in houses in the village continue to occur frequently and tremor remains elevated. Etna volcano: The strombolian activity inside Bocca Nuova crater has ended abruptly yesterday. Colima (Mexico) has entered a new eruptive phase withmore explosions during the past days. PopocatĂ©petl (Mexico): Activity has not changed significantly: there are 1-2 weak emissions per hour, sometimes producing small quantities of ash. Glow from the summit remains visible at night. Some small volcanic earthquakes (below M2) have been occurring in the past days as well. Santiaguito (Guatemala): The activity has remained essentially unchanged but lower than last week. During 14-15 Jan, few weak explosions occurred from the dome, and glowing avalanches were observed from the fronts of the active lava flows on its flanks. Pacaya (Guatemala): Increased steaming has been observed today, but otherwise, there has not been any new activity. Numerous small earthquakes continue to be visible as evidence of fluid movements under the volcano. Fuego (Guatemala): Activity has been decreasing with few explosions and the lava flow reducing its length to 300 m. Nicaragua’s San Cristobal, Masaya and Concepcion volcanoes have not shown appreciable changes in their (seismic) activity of varying amounts of volcanic earthquakes and tremor. Nevado del Ruiz (Colombia): No other activity than degassing has been reported recently. Seismic activity remains elevated but at relatively low levels. A swarm of earthquakes occurred under the volcano on 15 Jan afternoon. Very small, but numerous, earthquakes are occurring at Machin, Galeras, and Cumbal volcanoes in Colombia. Reventador (Ecuador): Strong seismic activity including some explosion signals and a hot spot visible on satellite images suggest that the lava dome in the summit crater continues to be active. Tungurahua is currently calm. Copahue (Chile/Argentina border): No surface activity and no glow has been observed, but there is elevated seismic activity of low energy with more than 1700 events detected between 15-16 Jan. Alert level remains
 at Orange because of the risk of sudden phreatic explosions. Lokon-Empung (North Sulawesi, Indonesia): Another explosionoccurred this morning at 09:33 local time. It was weaker than the previous ones and produced a plume rising to about 12,000 ft (3.6 km) altitude and drifting NE, VAAC Darwin reported. Kilauea (Hawai’i): Activity has been stable with good magma supply maintaining relatively high levels of the lava lakes and feeding lava flows that continue to reach the ocean. Sakurajima volcano in Japan has maintained a rythm of 2-3daily explosions with ash plumes rising to 6-10,000 ft (1.8-3 km) altitude. White Island (New Zealand): The tremor has increased significantly during the past 24 hours. If this is caused by the volcano (and not wind), it could suggest a new eruption under way, but there have been no reports of any activity so far. Kizimen (Kamchatka): The new lava flow from the summit dome continues to be active on the north-eastern flank of the volcano. Incandescence of the volcano summit, hot avalanches and strong degassing accompany this process, KVERT reports. Tolbachik (Kamchatka): The eruption still continues with active lava flows being fed by the southern vent. KVERT reports tremor at higher levels than during the past week.  –Volcano Discovery