2nd post: 'The boiler limits of Grímsvötn also show shear and collapse effects. After the water comes out, the volcanic system is losing pressure which may generate an eruption in the next few days, creating plumes of steam and ash.'
Would that be because the pressure of the water and ice above balances the pressure from below. It is well known that when glacial ice retreats land that is laid bare below rises.
' The water that was under the glacier that covers the volcano Grímsvötn , began to come out. A Jökulhlaup began to be created that rose more than 4 m, it is a matter of days before we begin to see columns of steam and ash in the main crater.'
The graphs show the average vertical motion of a seismometer per minute at three different frequency ranges (Hz). The vertical scale represents a change in output.
Grímsvötn (Icelandic pronunciation: [ˈkrimsˌvœhtn̥];[2]vötn = "waters", singular: vatn) is a volcano with a (partially subglacial) fissure system located in Vatnajökull National Park, Iceland. The volcano itself is completely subglacial and located under the northwestern side of the Vatnajökull ice cap. The subglacial caldera is at 64°25′N 17°20′W, at an elevation of 1,725 m (5,659 ft). Beneath the caldera is the magma chamber of the Grímsvötn volcano.
Grímsvötn is a basaltic volcano which has the highest eruption frequency of all the volcanoes in Iceland and has a southwest-northeast-trending fissure system. The massive climate-impacting Laki fissure eruption of 1783–1784 was a part of the same fissure system. Grímsvötn was erupting at the same time as Laki during 1783, but continued to erupt until 1785. Because most of the volcanic system lies underneath Vatnajökull, most of its eruptions have been subglacial and the interaction of magma and meltwater from the ice causes phreatomagmatic explosive activity.[citation needed]
Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water. They differ from exclusively magmatic eruptions and phreatic eruptions. Unlike phreatic eruptions, the products of phreatomagmatic eruptions contain juvenile (magmatic) clasts.[1] It is common for a large explosive eruption to have magmatic and phreatomagmatic components.
About the climate-impacting Laki fissure eruption of 1783-1784 the Wiki mentions, as to have an idea of what climate-impacting could mean:
The system erupted violently over an eight-month period between June 1783 and February 1784 from the Laki fissure and the adjoining volcano Grímsvötn, pouring out an estimated 42 billion tons or 14 km3 (3.4 cu mi) of basalt lava and clouds of poisonous hydrofluoric acid and sulfur dioxide compounds that contaminated the soil, leading to the death of over 50% of Iceland's livestock population, and the destruction of the vast majority of all crops. This led to a famine which then killed approximately 69% of the island's human population.[4] The lava flows also destroyed 21 villages.
The Laki eruption and its aftermath caused a drop in global temperatures, as 120 million tons of sulfur dioxide was spewed into the Northern Hemisphere. This caused crop failures in Europe and may have caused droughts in North Africa and India.
2020-21 threats of eruption
In June 2020, the Icelandic Meteorological Office (IMO) issued a warning that an eruption might take place in the coming weeks or months, following scientists reporting high levels of sulfur dioxide, which is indicative of the presence of shallow magma. IMO warned that a glacial flood as a result of melting ice could trigger an eruption.[20] No eruption occurred.
In September 2021, an increase in water outflow from under the Vatnajökull ice cap was reported. The water contains elevated levels of dissolved hydrogen sulfide, suggesting increased volcanic activity under the ice.[21] Jökulhlaup (glacial lake flooding) can occur before or after an eruption.
On December 4th 2021 a Jökulhlaup occurred from Grimsvötn into the Gígjukvísl river (average flow 2600 m3/s). It is believed that volcanic eruptions can occur after sudden pressure release due to reduced water level in the lake. The last time something similar happened was in 2004, 1934 and 1922.
300 miles off the coast of Oregon lies an active volcano that the world has never seen before, with a magma reservoir two thirds the length of Manhattan.
And this summer, a group of scientists from around the world spent 33 days on the Pacific Northwest ocean in a research vessel called Marcus G. Langseth, gathering images to create a 3D map of the behemoth and its magma chambers. The New York Times first reported the group's expedition and its findings.
Axial Seamount was first discovered in 1981 and has erupted three times since its discovery—in 1998, 2011 and 2015.
I looked up on Google Earth to find out where Axial Seamount is, and it appears to be about 100-150 miles from where the earthquake swarm is taking place. Here is a screenshot of the swarm and the Axial Seamount, which lies just next to the Brown Bear Seamount almost straight north from the swarm.
Here is a screenshot from Google earth of where exactly Axial Seamount is located (almost straight west from Portland).
So the earthquake swarm is not directly under the volcano Axial Seamount and perhaps too far away to be due to an awakening volcano, I think, though a connection is not to be dismissed entirely. If it is due to an awakening volcano, then perhaps there are other sleeping volcanoes (giants?) closer to the swarm, which hitherto have remained unnoticed.
If it not due to a volcano, then something else could be afoot like underground slippage and readjustment. Time will tell.
If it is due to an awakening volcano, then perhaps there are other sleeping volcanoes (giants?) closer to the swarm, which hitherto have remained unnoticed.
In looking further there is a named seamount which is located within the earthquake swarm and it is called Parks Seamount. This could be a better candidate, if volcanic activity is part of the cause for the current earthquake swarm in the waters of Oregon, though no history of eruption in historical times that I could find.
A seamount is a large geologic landform that rises from the ocean floor but that does not reach to the water's surface (sea level), and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to 1,000–4,000 m (3,300–13,100 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 m (3,281 ft) above the seafloor, characteristically of conical form.
The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea.[2] During their evolution over geologic time, the largest seamounts may reach the sea surface where wave action erodes the summit to form a flat surface. After they have subsided and sunk below the sea surface such flat-top seamounts are called "guyots" or "tablemounts".[1]
The Earth's oceans contain more than 14,500 identified seamounts[3] of which 9,951 seamounts and 283 guyots, covering a total area of 8,796,150 km2 (3,396,210 sq mi), have been mapped[4] but only a few have been studied in detail by scientists.
The death toll from the eruption of Indonesia's Mount Semeru has risen to 39, authorities said Wednesday, as rescuers scrambled to retrieve more bodies under the threat of further volcanic activity.
An increased volcanic-seismic unrest has been detected by the Vanuatu Meteorology and Geohazards Department (VMGD) as they reported yesterday.
The elevated activity is dominated by steam and gas emissions rising 250 meters height and wet tephra ejected to an approximate height of 10 meters above the lake.
The Volcanic Alert Level remains at Level 1.
People are advised to avoid the summit area of about 2 km radius and area of flowing creeks during torrential rains as says Danger Zones Map.
Source: Vanuatu Meteorology and Geohazards Department volcano activity update 9 December 2021
The USGS's surveillance cameras observed a strong short-lived explosion at about 15:15 local time today generating dense ash plume.
The height of the ash plume is unknown and was not reported yet nor by the Volcanic Ash Advisory Center Anchorage (VAAC) and the Alaska Volcano Observatory. If the eruption came without warning or it was accompanied by a detected precursor, these details need to be confirmed by the volcano observatory or VAAC.
Guest "Did you ever play the telephone game?" by David Middleton Hat tip to Ted... Message: Please find a qualified geologist to take on this nonsense.They cite "the conversation" as their authority.https://thehill.com/policy/equilibrium-sustainability/584770-equilibrium-sustainabilityToday is...
Maybe they were just trying to dance around the truth, thunderstorm indicates electrical activity in the atmosphere interacted with the magma fluid ?
Magnetic structures can store enormous amounts of energy that may be released through reconnection of magnetic field lines (MHD reconnection) leading to solar flares and stellar or even galactic eruptions. It is in this way that the Sun causes storms in the heliospherical magnetic field and ultimately aurorae and space weather.
In ideal MHD the topology of the magnetic field (the connectivity of the field lines) does not change. If a set of magnetic field lines is twisted into a knot, they will remain so. This means that it is very difficult to change the magnetic topology of some field configuration by MHD reconnection, if the resistivity is very low. It is thus possible to store large amounts of energy in the magnetic field by twisting it into a complex topology by the fluid motions. This energy can subsequently be released into heat and kinetic energy, if the scales of the magnetic field become very small leading to large magnetic gradients or if the resistivity increases. In this case the ideal MHD breaks down allowing magnetic reconnection to occur.
Magnetohydrodynamics (MHD) is the physical-mathematical framework that concerns the dynamics of magnetic fields in electrically conducting fluids, e.g. in plasmas and liquid metals. The word magnetohydrodynamics is comprised of the words magneto- meaning magnetic, hydro- meaning water (or liquid) and -dynamics referring to the movement of an object by forces. Synonyms of MHD that are less frequently used are the terms magnetofluiddynamics and hydromagnetics.
One could also ask, that since 70% of the earth is covered with water and thus a likely 70% of all volcanoes are under water, then why are they not erupting continuously with all that water seeping down?
The volcano seems to be getting even more active. The SO2 levels dropped on Saturday to under 3000 tons but have today increased to 53600 ton/day, close to a 20 fold increase.
After having been 15000 tons/day for the last week, today it dropped to 653 tons/day. I wonder how they got such specific number but apparently they at the same time have admitted that there is a great margin of uncertainty. If that is the case, then why not say between 600-700 or likely below 1000 tons. Anyway that is what they decided and though that could be a sign that things are coming to an end according to what they first mentioned a couple of months (below 3000tons/day was meant to be a sign of it coming to a close), then things could well change many times still, I suspect.
Etna • Sicily, Italy 13+14 Dec 2021 - (3357 meter / 11,014 ft varies)
So, Etna at first had a lateral effusive eruption in the evening of 13 Dec 2021, in which lava started to exit at the side of the mountain at 2200 meter height (I believe it was) in the Valle del Bove depression on the east side of the volcano. Yesterday, on 14 Dec 2021, Etna performed during daytime a new (small) paroxysm after a longer time.
A lateral eruption occurred on Etna last night, which so far has been purely effusive. The lava flow in Valle del Bove is several hundred metres long.
The tremor on Etna continued to rise during the night, fluctuating. The latest report from INGV states that there is neither increased seismicity nor unusual inflation before the opening of the new vent. The purely effusive Bocce in the Valle del Bove had opened at 6.06pm last night. It is located at an altitude between 2200 m and 2100 m. Within a few hours, the lava front reached a height of about 1700 m and moved in the area of Monte Centenari. The production rate is comparatively low and localities are not endangered.
Dr. Boris Behncke assessed the situation similarly to what I did yesterday and said that the activity is associated with that of the New Southeast Crater. There were no signs of a new magma rise. The lava produced contains little gas and is produced purely effusively. Most likely, it is melt that was in the conveyor system of New Southeast Crater and did not make the ascent to the crater. A similar eruption occurred in 2004 and lasted for several months.
The eruption differs from the huge eruptions in 1991-93 and 1981, which threatened localities and caused lava to travel several kilometres in a few hours. These eruptions were preceded by seismic crises along with inflation. Nevertheless surprising
14 Dec 2021 Latest (Paroxysm):
During the afternoon, the activity continued to increase and there was something like a small paroxysm. Above all, a dense eruption cloud of volcanic ash was produced. So far, the volcano did not produce a glowing lava fountain, or it was not visible on the photos.
The tremor reached a peak and then dropped steeply. In the meantime, however, it is rising again, which indicates that Etna is not finished yet!
Cumbre Vieja, LaPalma, Spain Photo Impressions 28 November - 13 December 2021
While I am at it... Here is another batch of astonishing photo impressions people as well photographers have made from the eruption on La Palma during the last 2+ weeks -
The image above comes form the sudden more explosive event, i believe happened on 13 Dec 2021.
After having been 15000 tons/day for the last week, today it dropped to 653 tons/day. I wonder how they got such specific number but apparently they at the same time have admitted that there is a great margin of uncertainty
This was on Saturday and the following day it decreased by half to under 400 tons/day. Yet now it has increased 10 fold to 3384 tons/day, so despite some thinking it is soon finished, then perhaps not. So far it has been going on for 88 days straight thus being the longest eruption in La Palma's recorded history.
The La Palma volcano has ceased all its activity this Tuesday night. "It does not emit lava, nor sulfur dioxide, nor does it register any sign of tremor or seismicity," confirmed sources from the National Geographic Institute (IGN). These sources consider it "unlikely", although not entirely rulable, that it will resume the activity.
Therefore, sources from the Volcanic Emergency Plan of the Canary Islands (Pevolca) have assured that they prefer to wait a few days before certifying their final death. The technical director of Pevolca, Miguel Ángel Morcuende, had already assured in the press conference on Tuesday that the activity of the volcano had fallen to "practically disappear", although they described the situation as an "impasse". Is this the end? Scientists are cautious when discussing the conclusion of the eruption.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
