Monday, April 25, 2016

GLOBAL VOLCANISM: The Latest Report Of Volcanic Eruptions, Activity, Unrest And Awakenings – April 24, 2016!

Klyuchevskoi volcano this morning with what is likely a new lava flow (KVERT webcam)

April 25, 2016 - EARTH - The following constitutes the new activity, unrest and ongoing reports of volcanoes across the globe.

Kliuchevskoi (Kamchatka): The activity of the volcano has intensified, in particular during the past 24-36 hours. KVERT reported that strong strombolian explosions produced an ash plume that rose to 8-9 km altitude that drifted more than 400 km to the SW.

Webcam images have been mostly unclear, but view from this evening (dawn in Kamchatka) suggest that a new lava flow might have started to descend the volcano's flanks, which would be a typical occurrence if the magma supply rate has indeed increased. An intense thermal anomaly is being recorded on satellite data as well.

KVERT alerted this morning that the "explosive eruption of the volcano continues. Ash explosions up to 19,700-26,240 ft (6-8 km) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft." The aviation color code was raised to ORANGE.


Sinabung (Sumatra, Indonesia): The volcano's current and long-lasting eruption (now well in its 3rd year) continues essentially unchanged: viscous lava slowly rises into the summit crater, building up a complex dome that over-spills as sticky lobes onto sections of the upper outer slopes on the southeastern side.


Explosion from Sinabung last Friday

When these steeply emplaced lava lobes become too large, they also become unstable and begin to collapse. These collapses generate glowing rockfalls and small to moderate pyroclastic flows when enough material rich in gas is involved. From time to time, accumulated gas trapped beneath the dome also gives way to vertical explosions. These explosions have been occurring almost daily over the recent months, producing ash plume that rise 1-2 km, typically.


San Cristobal (Nicaragua): The volcano had a series of new explosive eruptions on Friday, producing ash plumes that rose up to approx. 2 km above the summit crater, drifted south and caused moderate ash fall in areas up to 10-15 km south and southeast of the volcano, including Las Brisas, Santa Narcisa, and Chichigalpa town.

The new series of eruptions began on 22 April around 10:20 local time with a first explosion, followed immediately by a stronger one (image). Weaker explosions followed intermittently throughout the day, but activity seems to have faded again as of today.

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Ash plume from San Cristobal's eruption last Friday (INETER)

Whether these eruptions were caused by superficial steam explosions (phreatic activity) or involved new magma that has risen inside the volcano's conduit is unknown at the moment (without analysis of the ash and seismic and other parameters)

In any case, the volcano has been at elevated unrest for some time and might continue to do so for a while: unconfirmed minor explosions seem to have occurred earlier this year in February and similar, more significant explosions took place in March and June last year (2015).


Nevado del Ruiz (Colombia): The volcano produced a small ash plume today, Manizales volcano observatory reported to Washington VAAC. Webcam views are obscured by weather clouds.

Sporadic mild ash emissions have been occurring from the volcano from time to time during the past weeks.




- Volcano Discovery.






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