Volcanic Activity Worldwide: May11, 2016

Mount St. Helens (Washington)

Shiveluch (Kamchatka): (9 May) KVERT reported that during 21-29 April lava-dome extrusion onto Sheveluch’s N flank was accompanied by strong fumarolic activity, dome incandescence, ash explosions, and hot avalanches.
Satellite images showed an intense daily thermal anomaly over the dome. The Aviation Color Code remained at Orange.

Mount St. Helens (Washington): Since the beginning of 2016, a swarm of small earthquakes has been occurring at under the volcano, suggesting that another phase of magma recharge is currently taking place.
The recorded quakes have been at shallow depths between 2-7 km under the summit and ranged in magnitudes from 0 (or less) to 3 on the Richter scale, i.e. they are all tiny. Only rarely, they exceeded magnitude 2 and only a very few might have been felt by persons being very close.

USGS volcanologists and seismologists interpret the vertical area where these quakes occurred as the area where a small amount of fresh magma has been rising into the volcano’s plumbing system (a magma chamber). Magma rises, pressurizes surrounding rock to make space and causes fracturing = tiny quakes.
The current swarm is only one of a series of similar swarms that have taken place since 1988, including some much more energetic ones (such as during 1998-99). Most such earthquake swarms, not only at Mt. St. Helens, but at almost any volcano, are NOT followed by eruption, or at least not immediately. In the case of Mt. St. Helens, the large earthquake swarm during 1998-99 preceded the small effusive activity during 2004-2008 by 5 years.

Nevados de Chillán (Central Chile): (9 May) Two new phases of ash explosions occurred at the volcano this morning. The first and strongest occurred at 13:03 local time, generating a dense ash plume that rose 1700 m above the crater, followed by a weaker series of ash emissions at 14:40.
The eruption plumes caused moderate ash falls in areas up to a few km downwind (north) of the crater as well as small mud flows on its upper slopes. The latter were the result of rapid interaction of hot tephra (the erupted fragmented material) with snow.

Currently erupting:

Alaid (Northern Kuriles): intense thermal signal from summit crater, strong degassing (updated 31 Mar 2016)
Ambrym (Vanuatu): active lava lakes in several craters (updated 18 Feb 2016)
Aso (central Kyushu, Japan): degassing, sporadic steam / ash explosions (updated 8 Mar 2016)
Batu Tara (Sunda Islands, Indonesia): strombolian explosions, ash plumes up to 500 m, extrusion of a small lava dome with rockfalls (updated 28 Nov 2015)
Chikurachki (Paramushir Island): new eruption since end of March 2016 (updated 31 Mar 2016)
Colima (Western Mexico): sporadic small explosions (updated 31 Mar 2016)
Copahue (Chile/Argentina): seismic unrest, occasional ash venting (updated 22 Mar 2016)
Dukono (Halmahera): mild strombolian activity, continuous intense ash emissions (updated 21 Mar 2016)
Erebus (Antarctica): active lava lake in summit crater (updated 8 Dec 2014)
Erta Ale (Danakil depression, Ethiopia): overflowing lava lake (updated 2 Mar 2016)
Fuego (Guatemala): lava flows on S and W flanks, lava fountaining from summit vent (updated 11 Apr 2016)
Ibu (Halmahera, Indonesia): stromolian and phreatomagmatic explosions (updated 29 Oct 2015)
Karymsky (Kamchatka): occasional small explosions, thermal anomaly (updated 1 Mar 2016)
Kilauea (Hawai’i): new lava flow from vents on NE flank of Pu’u ‘O’o (updated 28 Apr 2015)
Kliuchevskoi (Kamchatka): mild strombolian activity in summit crater (updated 7 Apr 2016)
Masaya (Nicaragua): active lava lake in summit crater since mid Dec 2015 (updated 3 Apr 2016)
Momotombo (Nicaragua): intermittent vulcanian explosions (updated 29 Mar 2016)
Nevado del Ruiz (Colombia): intermittent explosions, steaming, ash venting (updated 31 Mar 2016)
Nyiragongo (DRCongo): new vent on crater floor (updated 8 Mar 2016)
Ol Doinyo Lengai (Tanzania): effusion of natrocarbonatite lava inside the crater (updated 8 Jul 2013)
Pacaya (Guatemala): intense spattering from intra-crater cone (updated 29 Mar 2016)
Popocatépetl (Central Mexico): degassing, sporadic explosions, slowly growing lava dome (updated 4 Apr 2016)
Rabaul (Tavurvur) (New Britain, Papua New Guinea): lava fountains, ash emissions from Tavurvur cone (updated 12 Sep 2014)
Reventador (Ecuador): lava flow on SW flank (updated 24 Feb 2016)
Sakurajima (Kyushu, Japan): sporadic vulcanian explosions from Minamidake and Showa crater (updated 8 Apr 2016)
Sangay (Ecuador): small strombolian activity in summit crater (updated 4 Apr 2016)
Santiaguito (Guatemala): intermittent explosions from Caliente dome, strong degassing (updated 13 Apr 2016)
Semeru (East Java, Indonesia): growing lava dome, lava flow, strombolian activity (updated 14 Feb 2016)
Shiveluch (Kamchatka): growing lava dome (updated 31 Mar 2016)
Sinabung (Sumatra, Indonesia): continuing pyroclastic flows (updated 31 Mar 2016)
Stromboli (Eolian Islands, Italy): weak, intermittent strombolian explosions (updated 31 Mar 2016)
Suwanose-jima (Ryukyu Islands): strombolian explosions in Ontake crater (updated 11 Apr 2016)
Tungurahua (Ecuador): large and frequent explosions, ash columns rising several km (updated 9 Mar 2016)
Ubinas (Peru): sporadic vulcanian explosions (updated 16 Jan 2016)
Villarrica (Central Chile): lava lake in summit crater, spattering, strombolian explosions (updated 4 Apr 2016)
Yasur (Tanna Island, Vanuatu): ash emissions, weak strombolian explosions (updated 13 Nov 2015)
Zhupanovsky (Kamchatka, Russia): steaming / degassing (updated 31 Mar 2016)