It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
originally posted by: Nidwin
As the dyke and it's magma flow has now a "clear" path to pass by and the main push is more N-E where it runs into "resistance" the stress on the Askja Caldera has been releaved.
"These strong earthquakes are the consequence of magna streaming out of the chamber beneath the caldera", says Pall Einarsson, professor of geophysics at University of Iceland´s Institute of Earth Sciences. "The magma chamber is clearly subsiding, thus reacting to the considerable amount of magma that has been streaming out towards the dike intrusion," says Einarsson. "Analysis of these earthquakes supports this conclusion, as well as nearby GPS measurements of land deformation. We call this pressure changes in the roof of the magma chamber; in effect, the top of the volcano is sinking ever so slightly."
Laki or Lakagígar (Craters of Laki) is a volcanic fissure in the south of Iceland, not far from the canyon of Eldgjá and the small village Kirkjubæjarklaustur. Lakagígar is the correct name, as Laki mountain itself did not erupt, but fissures opened up on each side of it. Lakagígar is part of a volcanic system centered on the Grímsvötn volcano and including the Þórðarhyrna volcano. It lies between the glaciers of Mýrdalsjökull and Vatnajökull, in an area of fissures that run in a southwest to northeast direction.
The system erupted over an eight-month period between 1783 and 1784 from the Laki fissure and the adjoining Grímsvötn volcano, pouring out an estimated 14 km3 (3.4 cu mi) of basalt lava and clouds of poisonous hydrofluoric acid and sulfur dioxide compounds that killed over 50% of Iceland's livestock population, leading to a famine that killed approximately 25% of the island's human population.
The Laki eruption and its aftermath caused a drop in global temperatures, as sulfur dioxide was spewed into the Northern Hemisphere. This caused crop failures in Europe and may have caused droughts in India. The eruption has been estimated to have killed over six million people globally, making the eruption the deadliest in historical times
originally posted by: Ezio313
Guys, I have a question. Can this fissure eruption evolve into a total collapse of the caldera and result in an eruption equivalent to a VEI 6 eruption?
The fissure eruption is continuing at a stable level with little variation. A curtain of lava fountains up to 70 m high is being erupted above the fissure and pahoehohoe type lava flows are expanding to several kilometers around it, forming a growing flat lava flow field.
The effusion rate along the fissure vent has been estimated to be up to an impressive 1000 cubic meters per second.
Update from IMO this morning:
"No explosive activity is observed, the eruption remains an effusive lava eruption. Visual observation by webcam and low level volcanic tremor on seismometers do not show any obvious changes since evening.
The (latest) eruption started around 04:00 GMT Sunday, on the same fissure which erupted Friday.
According to scientists, the latest eruption is roughly the same size as the one at Eyjafjallajokull in 2010, which grounded flights throughout northern Europe. However, no volcanic ash has been detected on radar
Sunrise Today: 6:10 AM↑ 69° East
Sunset Today: 8:44 PM↑ 291° Northwest
Moonrise Today: 3:09 PM↑ 132° Southeast
Moonset Today: 10:08 PM↑ 227° Southwest
originally posted by: Nidwin
This is from the latest report on Icelandic Met office webpage
n the broader Askja region, most events were located at Herðubreiðartögl, the strongest event there was M2.9 at 02:56. This area is a quite common place for seismic activity, the activity now is not necessarily caused by increased stress due to the intrusion (the tip of the intrusion is about 25 km SW of this cluster). Askja volcano itself was seismically quiet last night.
I'm not convinced of this statement, especially the tip of the dyke.
I've been keeping an eye on the quakes around Askja and the pattern I see is that the dyke and it's magma flow is still on the move in a N-E direction and has past the Askja Caldera. The seismic activity seen past days in the Askja Caldera was simply the result of the stress caused by the dyke passing by and moving up N-E. As the dyke and it's magma flow has now a "clear" path to pass by and the main push is more N-E where it runs into "resistance" the stress on the Askja Caldera has been releaved.