Volcanos

Roundup of Global Volcanic Activity:

Stromboli (Eolian Islands, Italy): The strength of explosion signals and tremor seem to have increased this morning. A small lava out-spill of lava from the northern breached rim of the NE crater as well as dust trails from numerous blocks rolling down the Sciara can be seen on the webcams.

Etna (Sicily, Italy): After a brief period of activity at the Bocca Nuova crater, strombolian activity shifted to the New SE crater on the night of 22 January. This much stronger activity has continued into 24 January.

Bárdarbunga (Iceland): An earthquake swarm at depths between 2-10 km about 8 km NE of Bardabunga volcano under the Vatnajökull icecap has started. The swarm appears to contain relatively large quakes, including a magnitude 3.8 quake, which, if magmatic origin, could mean a shallow intrusion, that potentially could lead to an eruption.

Gorely (Southern Kamchatka): Strong and moderate gas-steam activity were observed. Seismic activity is moderate.

Kizimen (Eastern Kamchatka (Russia)): A new lava flow extrudes from the summit on the north-eastern flank of the volcano. Incandescence of the volcano summit, hot avalanches and strong gas-steam activity accompany this process. Seismic activity is at moderate levels.

Tolbachik (Kamchatka, Russia): The explosive-effusive eruption continues with little changes. According to an eyewitness communication on actif-volcans, activity goes on from one of the new cones on the southern fissure, which produces near-continuous strombolian activity, at times merging into more or less sustained lava fountains. The vent continues to aliment fluid lava flows. KVERT reports that tremor increased again a bit compared to yesterday. A low steam and ash plume rises from the eruption.

Sakurajima (Kyushu): The volcano remains quite active, with an elevated number of explosions. Yesterday (22 Jan), there were at least 5 with ash plumes reaching 6-9000 ft (1.8-2.7 km). This is a lot considering the long-term average of 1-2 per day.

White Island (New Zealand): Tremor and hydrothermal activity at the surface remain high. In addition to strong tremor, volcanic earthquakes (red lines on seismogram) can be identified within the strong seismic signal as well. They could indicate magma moving upwards and be a warning sign for an impending eruption.

Colima (Western Mexico): Rockfalls and small volcanic quakes possibly accompany small emissions from the volcano. A 4.7 regional quake off the western coast of Mexico (large signal) also appears on last evening's seismogram.

Concepción (Nicaragua): A phase of increased internal activity occurred over night.

San Cristobal (Nicaragua): After a decrease yesterday, seismic activity reflecting internal unrest has increased today again.

Masaya (Nicaragua): Volcanic tremor has generally been near background, but a slight increase is visible today.

San Salvador (El Salvador): Small volcanic quakes and weak tremor are visible at the seismogram, but within normal levels for this active volcano.

San Miguel (El Salvador): Numerous volcanic quakes and bursts of weak tremor continue to be seen frequently on the seismic recording.

Nevado del Huila (Colombia): Activity has remained stable. The volcano is emitting a white plume of steam and gas. Internal activity remains at weak levels, with a total of 88 events registered by Popayan Observatory during the past week.

Galeras (Colombia): A slight increase in seismic activity was reported by Pasto Observatory. Most seismicity was related to fluid movements within the volcano, some by degassing and light ash venting, which was observed on 16 and 21 January. Steam plumes rose to a maximum of 1000 m above the crater, and measured SO2 levels were at moderate levels.

Nevado del Ruiz (Colombia): Numerous small earthquakes continue and a strong SO2 plume is visible on the latest NOAA satellite image, suggesting a phase of elevated (degassing) activity.

Cumbal (Colombia): A slight increase in seismicity related to internal fluid movements during the past week. Degassing as the only surface activity was observed on clear days.

Sotará (Colombia): Seismic activity remains barely above background. During the past week, INGEOMINAS reported a total of 13 mostly weak-energy events.

Reventador (Ecuador): From 09:00 (local time) 21 Jan, a strong increase in seismic activity occurred, dominated by low frequency tremor, possibly associated with fluid pressurization and movements of magma inside the conduit of the volcano. At night, the volcano was clear and incandescent material could be seen in the crater.

Cotopaxi (Ecuador): Another pulse of volcanic earthquakes is in progress under Cotopaxi volcano. Such swarms have been occurring several times recently, but for now, can be considered as part of the normal behavior of an active, but currently dormant volcano.

Tungurahua (Ecuador): The volcano remains calm with only few tiny earthquakes visible. Lahars generated by rain remobilizing loose deposits remain a major hazard inside drainages around the volcano.

Copahue (Chile/Argentina border): Seismic activity increased significantly during 22 Jan. No eruptive activity at the surface has occurred so far, and the official alert level of the volcano remains at "Yellow", but with "Special Attention" (corresponding to "orange" in our classification). Until 09:56 local time (12:56 GMT) on 22 Jan, seismic activity had remained at low levels, both in occurrence of earthquakes, the energy released and the signal intensity of tremor associated with fluid movements inside the volcano. Then, at that time, there was a significant long-period (LP) earthquake and 3 hours later, shallow lower amplitude events started to occur. At 13:20 local time, another LP earthquake of relatively strong intensity occurred and was followed by a seismic swarm with mostly long period events that continued for 20 minutes.

Michael (United Kingdom, South Sandwich Is): No further hot spots have been noted recently on MODIS data. Status is set back to "green".