This is an archived part of our Daily Volcano Activity report.
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This report was compiled out of many information sources by Armand Vervaeck, Jens Skapski and Rodger Wilson
Enormous earthquakes ‘are missing’ from records (December 12, 2013)
Research suggests that half of all quakes measuring more than 8.5 in magnitude that hit in the 19th Century are missing from records. Scientists are scanning historical documents for the lost tremors. The findings are presented at the American Geophysical Union Fall meeting in San Francisco. Dr Susan Hough from the US Geological Survey said: "If you try to make a statistical case there are too few earthquakes in the 19th Century."
Read the full BBC article here
Decoding the source of the 2011 Japan tsunami (December 11, 2013)
In the powerful earthquake off Japan in 2011, the size of the destructive tsunami it spawned caught scientists by surprise. But they soon learned why the waves were so large: measurements showed that part of the seafloor along the fault moved as much as 50 meters, or 55 yards, to the east, displacing an enormous amount of water.
That degree of movement, the largest ever measured for an earthquake, surprised scientists, too. The quake occurred in a subduction zone, where one of the planet’s tectonic plates dives beneath another. It was thought that the largest slip would occur at greater depths, and that shallower parts of the fault, nearer the seafloor, would move less.
Read the full "New York Times" article here
A beautiful new Etna paroxysm yesterday (December 3, 2013)
New Japanese island (December 3, 2013)
Reader Annette Schoerner commented :
As reported in Japanese media, the new volcano Island near to Ogasawara Nishinojima is here to stay. In this video from December 2, taken from a coast guard heli, it is said, that it is already grown to 2.5 the size from its first discovery on November 21, mainly to the east. Activity is still going on, smoke (yesterday it was greenish white) rises up to 2000 m and lava streams could be seen. If the island continues to grow, it is expected to merge with Nishinojima.
Rodger Wilson reporting from Central America, where he is working now (Nov.30, 2013)
Increased and now steady elevated volcanic tremor at Fuego volcano (Guatemala) (station FG3), an earthquake swarm yesterday at Cumbal volcano (Colombia) (station MEVZ), and a new burst of activity at Reventador volcano (Ecuador) (station CONE) during the past day.
Experience the shaking near the epicenter of a very strong earthquake
Very few cameras have ever been recorded the shaking in places that experienced truly extreme ground motions (the images shown are mostly recorded by cameras a couple of hundred km from the epicenter). One of the best video's of strong (devastating) motion was recorded during the 1995 Kobe earthquake (Magnitude 6.9), in which a sleeping Japanese office worker is awakened and then chased around the room by furniture. Let's hope you never have to experience this, but in case you should : be prepared
@JohnSeach reports via Twitter today
- 7 km long lava flow at Kilauea volcano, Hawaii. Active lava lake in summit crater.
@JohnSeach reports via Twitter a little earlier (Nov. 26 11:07 UTC) :
- Sinabung volcano, Sumatra, Indonesia. Continuous ash emissions to 18,000 ft. - Aviation code RED.
Sicily - Etna, November 23 - living near a volcano = sometimes special raindrops !
New islands in Pakistan (due to the massive earthquake) disappeared gain in the ocean !
Earlier scientists have reported that the islands were actually "Mud volcanoes" (as we described it in our in-depth earthquake article) and would vanish again in the waters, but we (ER) are surprised that the process did happen so quickly. The same happened after a massive earthquake shortly after the second world war but there were no records at the time about the time that it went underwater again.
The new Island attracted many tourists and fisherman hired their boats to tourists for a lot of money. This lucrative business has ended now.
Excerpt of the article describing the event :
"The island appeared a half mile off the port city of Gwadar several hours after a magnitude 7.7 earthquake hit interior Pakistan Sept. 24, Voice of America reported. The epicenter of the quake was in Baluchistan, about 250 miles from the coast. Initial reports from scientists said the island was about 60 feet above sea level, about 500 feet long and 600 feet wide.
Abdul Rahim, a biologist with World Wide Fund Pakistan, described the island's surface as "mostly muddy" and covered with large rocks and stones. The island has begun to disappear and is now about 10 feet underwater "and the process is ongoing," he said.
Read the full article here
Etna eruption video of November 23 2013
New Volcano Island in Japan
A volcanic eruption has created a new island in the seas 620 miles south of Tokyo
Footage showed clouds of heavy smoke, billowing steam and waters roiling over the newly-formed crater. The newly-formed land is off the coast of Nishinoshima, a small, uninhabited island in the Ogasawara chain. Embedded video courtesy BBC
Rodger Wilson volcano overview of November 15
Not sure if you're near the internet right now,...but just in case!
Internal activity is slowly ebbing within Veniaminof volcano (Alaska Peninsula) (station VNWF) as it continues to wind-down from a period of eruptions that stretched through this past summer.
Seismicity remains elevated along a zone of northwest-trending, en-echelon faults that stretches from Mount Hood volcano (OR) through Mount Saint Helens (WA). A similar trend is visible just south and west of Mount Rainier volcano (WA). A burst fo seismicity occurred overnight beneath the southeastern flank of Newberry volcano (OR) possibly along a similar northwest trending fault zone which bisects the volcano.
Popocatepetl volcano (Mexico) continues to be (mostly) internally active. Exhalations of gas and some ash have remained steady at the volcano, averaging about two events per hour over the past few weeks.
While volcanic tremor continues unabated at Pacaya volcano (Guatemala) (station PCG), levels of seismic/eruptive(?) activity appear to have eased at both Fuego (station FG3) and Santa Maria (station STG3) volcanoes over the past few days.
Volcanic tremor remains unsteady at Masaya volcano (Nicaragua) (station MASN).
A short episode of volcanic tremor struck San Miguel volcano (El Salvador) (station VSM) late yesterday. Otherwise,...the volcano exhibits its' "normal" high level of volcanic earthquakes.
The tempo of seismicity at Turrialba volcano (Costa Rica) (station VTUC) has risen (again) since yesterday.
Numerous small volcanic earthquakes continue to affect Cumbal volcano (Colombia) (station MEVZ).
Seismicity has fallen strangely silent at Tungurahua volcano (Ecuador) (station RETU) overnight (volcanic "stage fright" because Armand is there to watch the activity?). Not so for Reventador volcano (station CONE).
Armand : Unfortunately Tungurahua was merely hidden in the clouds and NO explosion was heard during the time that i spend in Banos and near the volcano. The picture below was one of the few moments the rim became visible. The day before we saw a minor explosion while driving on the Avenue of the Volcanoes. Strong enough though to create a big ash cloud against the then still blue sky.
Rodger Wilson volcano overview of November 11
Conditions have remained staid at nearly all the volcanoes we watch over the past week,...save for the Guatemalan volcanoes.
Internal rumbling, in the form of small volcanic earthquakes, continues with no outwardly visible activity at Veniaminof volcano (Alaska Peninsula) (station VNWF) today.
Low-level seismicity affects the "South Moat" of Long Valley Caldera (CA) (station MLC).
A significant earthquake swarm occurred Popocatepetl volcano (Mexico) last week, though there has been no change in relatively low-level eruptive activity at the volcano.
At the Guatemalan volcanoes,...monotonous volcanic tremor continues at Pacaya volcano (station PCG). The tremor indicates gas streaming, which propels nearly continuous strombolian activity within MacKenney Crater. Numerous volcanic earthquakes, with occasional small explosions and emission tremor (accompanying lava extrusion) continue at the Santiaguito Dome Complex (Santa Maria volcano) (station STG3), and periods of tremor have recently increased in frequency and duration at Fuego volcano (FG3) which is also emitting lava.
In Nicaragua,...volcanic tremor has recently become unsteady (periodically increasing in amplitude) at Masaya volcano (station MASN).
Internal activity has changed (increased) recently at Turrialba (station VTUC) and Poas (station POA2) volcanoes (Costa Rica). At Turrialba, small volcanic earthquakes increased in number late last week, though their frequency now appears to be diminishing. Volcanic/hydrothermal tremor has increased in amplitude at Poas volcano during the past 24 hours.
Small earthquakes, accompanied by increased(?) gas emission, continues at Cumbal volcano (Colombia) (station MEVZ), and volcano-tectonic earthquakes have increased (including a "felt" earthquake yesterday) at Galeras volcano.
Tungurahua volcano (Ecuador) (station RETU) continues to "chug" and murmer internally (with diminishing vigor), while to the northeast, Reventador volcano (station CONE) has fitfully produced small ash clouds during this past week.
Do you have any direct observations for us Armand?
Armand : I am today at an altititude of 3500 meter only a few kms from the Cotopaxi volcano. Cotopaxi was most of the day surrounded by thick clouds but luckily the sky opened for some minutes and a great snow capped (in fact glaciers) volcano showed himself.
Tomorrow we will head to Banos and the active (although diminished) Tungurahua volcano.
The reason why this report was interrupted was that Armand was traveling the Galapagos islands with only a poor internet connection on the ship. Now back in Quito with a couple of volcanoes coming on. The weather ouitlook is not so promising for Tungurahua unfortunately but lets fingers cross
Rodger Wilson volcano overview of November 5
Seismicity continues to be elevated in the middle and deep crust (12-15+ km) surrounding Mount Saint Helens volcano (Cascade arc) (USA). We have observed the activity there since at least this past Spring. I interpret the activity to be the result of deep magma injection (due the events being spacially related to the volcano and that seismicity local to dome complex has since become elevated during the past few months. Injection is likely centered too deep to be obviously detected by GPS and other deformation measurements). The activity has some utility in that it can "point to" a volcano which should be watched a little more closely, but as deep magma injection undoubtedly occurs at all active volcanoes from time to time (without ensuing eruption), it is of limited use as a "predictor". But. before you "throw the baby out with the bath water", see my entry for Cumbal volcano below.
Volcanic tremor at Pacaya volcano (Guatemala) (station PCG) has maintained a steady beat through this Fall, accompanying sub-continuous strombolian explosive activity at a new cinder cone within the Mackenney Crater. Volcanic tremor (some of it apparently harmonic in nature) has remained frequent (along with short explosions) at Fuego volcano (station FG3). The most interesting activity has been at Santa Maria volcano (station STG3), where over the past month inter-eruptive seismicity has been at the highest level I've observed since I've watch Santa Maria.
Numerous small seismic events (and occasionally tremor) again affect Turrialba volcano (Costa Rica) (station VTUC) with no apparent outward effect.
The Colombian volcano Nevado Del Ruiz, Cumbal, and Galeras have shown some "umph" the past few days. A swarm of over 70 small events occurred at Cumbal volcano (station MEVZ) on 03 November and small events remain frequent at the volcano. Breaks in the clouds at Cumbal have revealed continued periods of stronger(?) degassing at the volcano. Seismicity away from Cumbal proper (but spatially-related to similar to that at Mount Saint Helens) also continues. "Felt" earthquakes occurred overnight at both Galeras (station CUVZ) and Nevado Del Ruiz (station OLLZ) volcanoes. The magnitude M3.5 event at Nevado Del Ruiz was part of a larger earthquake swarm which continues at a reduced level at the volcano.
Low-frequency (volcanic), and some small explosion earthquakes are still being recorded on seismograms at Tungurahua volcano (Ecuador) (station RETU), though activity at the volcano continues a slow decline. On the other hand, Reventador volcano (station CONE) appears to be "revving-up" again after taking a short break in activity last week.
Rodger Wilson volcano overview of October 28
Mostly quiet, or at least status quo for the volcanoes we watch these past few days.
Of the new activity, stronger venting of steam and apparently non-juvenile ash has subsided at Zuphenovsky volcano (Kamchatka Peninsula) following a sizable phreatic outburst at the volcano last Thursday. The question is, why did the Zuphenovsky hydrothermal system fire-off at this point in time?
A neat occurrence during Saturday's(?) paroxysm at Mount Etna (Italy), the Northeast Crater (largely inactive since the late 1990's) unleashed a dark cloud of ash. I remember standing on the northern lip of the Bocca Nuova in the mid-1990's, enjoying an eruption of the Northeast Crater with two friends when suddenly (...and silently!) the Bocca unleashed a similar dark cloud! Needless to say, we beat a hasty retreat toward the base of the cone as the cloud quickly overshadowed us. Apparently, the plumbing system beneath the summit of Etna dips at an angle such that eruptions at one vent, be it the Voragine, Bocca Nuova, or the Northeast or Southeast Craters, often results in collapses within adjacent vents that in-turn produce what appear to be ash expulsions.
Volcanic tremor (accompanying strombolian eruption) at Pacaya (Guatemala) (station PCG) has fluctuated in amplitude the past few days, seismicity remains high at Santiaguito Dome Complex (Santa Maria volcano) (station STG3), and activity has been alittle more subdued at Fuego volcano (station FG3) during the same period.
Volcanic tremor and small volcano-tectonic earthquakes continue to periodically rattle Turrialba volcano (Costa Rica) (station VTUC).
Another "felt" earthquake occurred near Cumbal volcano (Colombia) (station MEVZ) today.
Tungurahua volcano (Ecuador) (station RETU) has given a primer on pyroclastic flow seismic signals (generally impulsive onsets with long, trailing codas) this past week, but activity at the volcano has fallen-off during the past 24 hours. The level of eruptive energy at Reventador voclano has also declined in the past few days.
Etna (Sicily) now erupting (07:51 UTC)
OLDER ARCHIVED PARTS OF THIS REPORT :
2013 : July 8 - July 31
2013 : June 24 - July 7
2013 : June 8 - June 23
2013 : May 26 - June 7
2013 : June 8 - August 20
2013 : August 21 - October 27
2013 : October 28 - December 12