By Maria Gallucci@email@example.com
on August 20 2014 10:45 AM
An intense earthquake swarm continues to rattle Iceland’s Bardarbunga volcano, adding to fears that a potential eruption could disrupt the region’s air traffic. Weather officials say they detected about 1,000 small quakes through Tuesday night, which were triggered by an unusually strong earthquake on Monday. The tremors are tied to the increasing movement of magma underground.
“Similar to recent days, two pulses of comparably strong seismic activity have been measured between 04:00 (GMT) and 08:00 this morning, as well as 16:00 and 18:30 in the afternoon,” the Icelandic Met Office wrote on Tuesday night, according to a post published this morning.
Met officials this week issued an “orange” aviation warning – the fourth-highest on a five-grade scale – following a magnitude-4.0 earthquake on Monday, the strongest in the region since 1996. The warning indicates “heightened or escalating unrest with increased potential of eruption.” The Bardarbunga last erupted in 1910, though according to the Met Office, seismic activity has been gradually increasing around the volcano over the past seven years.
Strong earthquakes and geomagnetic jerks: a cause-effect relationship?
ABSTRACT Secular variation of the geomagnetic field observed at the Earth's surface has been found to undergo impulsive accelerations Gerks) lasting less than a few years. In this paper the relations between jerks and the occurrence of strong earthquakes (Ms ≥ 7.0) is analysed for this century , disclosing a positive correlation between the maximum number of recorded strong earthquakes and jerk occurrence. Analysing only very strong earth- quakes (Ms ≥ ; 8.0) the jerks seem to take pIace with a time delay of about 2-5 years with respect to earthquake occurrence. Reliable processes that could justify this intriguing correspondence are suggested.
Earth's Magnetic Field Is Weakening 10 Times Faster Now
by Kelly Dickerson | July 08, 2014 11:29am ET
Earth's magnetic field, which protects the planet from huge blasts of deadly solar radiation, has been weakening over the past six months, according to data collected by a European Space Agency (ESA) satellite array called Swarm.
The biggest weak spots in the magnetic field — which extends 370,000 miles (600,000 kilometers) above the planet's surface — have sprung up over the Western Hemisphere, while the field has strengthened over areas like the southern Indian Ocean, according to the magnetometers onboard the Swarm satellites — three separate satellites floating in tandem.
Today has certainly has seen a qualitative change in the quakes. The quake pattern within the fissure complex NW is of relatively smaller quakes, and the largest of them are at the bottom of the 15 km high stack. This suggests that either there’s more material trying to flow into the fissure there, or else the area has become more constricted. The CGPS shows instead it has continued to open wider, then it must mean more material is trying to rise into the fissure complex more quickly as it opens more. Magma is apparently trying to rush into it from below.
The quakes in Bardarbunga are more focused in the caldera and much larger than any to date. This continues the rise in numbers and mag trend established yesterday. The quakes are all stacked central to the caldera within 10 km of the surface, with mag ~3 top and bottom, and the big mag 4.7 right in the center around 5 km depth. The magma has begun to lift and stress Bardarbunga’s collapsed roof-plug structures.
As a result I don’t think it’s now reasonable to say there’s no evidence of magma rising towards the surface. If magma were not accruing and rising higher the bigger quakes would not be there. So the magma chamber is pressurizing and no longer able to relieve its pressure via flowing out into the fissure complex, as the magma in it has risen and is now pushing back.
Which means the pressure will soon be rising everywhere within the two main intrusions, or else it will try to extend the opening and infilling of the fissure complex to the SW. But Bardarbunga may have to develop a ‘head’ of higher magma pressure before that takes place – it may not open.
I can’t see the caldera filling much without extending and squeezing all the fissures full of magma that it can, and it may now have done that. At which point lifting the roof of the caldera is the only outlet left to ease the influx of magma pressure.
Opinion: from what is observed so far I think magma will continue to rise even if a large eruption commences, because the quantity of magma on the rise as delineated by the numerous rapid-fire quakes down to ~25 km, suggests a very large volume of melt is moving, and much of it is well below 10 km depth still. If a large eruption occurs the pressure drop will result in a renewed rising magma surge.
originally posted by: ketsuko
There has been a running commentary on threads on Watt's Up with That and Volcano Café on this one. One of the posters on Watt's has been watching this one very closely and feels the magma may be showing signs of moving vertically.
originally posted by: ElectricUniverse
The most profound change is happening to the speed in which the magnetic north has been moving towards Siberia. In the last years, since mid 1990s, the speed of the movement of magnetic north has increased to 50-60 km, meanwhile it used to be moving for the last 100 years at an average rate of 10-20 km, and now in the past 6 months it has been weakening faster. So something is causing these changes to accelerate.( magnetic south is not moving as fast)
For more information, including a video produced by ESA explaining what has been happening to the Earth's magnetic field go to the link below.
The theory of what is probably causing this is the rapid movement of plumes (large volumes of molten lava) from the core of the Earth to the upper mantle. The specific plume that could be causing this rapid acceleration of magnetic north is the sudden movement of a plume into the Greenland mantle. Meanwhile there should be two plumes moving into the mantles of north America and the other in south America that would explain the weakening effect of the Earth's magnetic field on the western hemisphere.
However we know of no core mechanisms that could be causing this rapid acceleration and weakening of Earth's magnetic field. What we do know is that there are similar geomagnetic jerks that have occurred and have left signs of these events in the geological record of Earth and have been 10,000 times too fast and 100,000 times to large in magnitude to be caused by any core mechanism.
2013-05-10 14:41:49.0 63.90 N 22.39 W 10 4.0 ICELAND REGION
2013-05-10 14:34:23.4 63.66 N 23.26 W 13 3.7 ICELAND REGION
2013-05-10 13:55:21.5 63.71 N 23.32 W 12 3.3 ICELAND REGION
2013-05-10 03:20:46.5 63.70 N 23.22 W 14 3.4 ICELAND REGION
2013-05-10 01:34:28.0 64.03 N 22.35 W 2 3.7 ICELAND
2013-05-10 01:06:04.0 63.80 N 23.20 W 2 4.2 ICELAND REGION
I'm wondering if those list is complete, just 6 in year 2010 ?
Slamet volcano (Central Java, Indonesia): eruption increases, powerful strombolian explosions
Activity at the volcano has increased and VSI raised the alert level to "siaga", 3 on a scale of 1-4. The mild strombolian activity which had been going on for months at the volcano has become more and more intense since the beginning of September. Some explosions in the past days have been strong enough to eject incandescent material to all over the summit cone of the volcano.
Kilauea volcano update: Lava slows, misses first homes for now
"Between September 10 and 12, the June 27th flow advanced north-northeastward at an average rate of 250 m/day (820 ft/day). By the afternoon of September 12, the flow had advanced approximately 14.9 km (9.3 miles) straight-line distance from the vent, or to within 170 m (560 ft) of the boundary between the Wao Kele o Puna Forest Reserve and the northwest corner of Kaohe Homesteads. At the average rate of advancement of 250 m/day (820 ft/day) since September 10, we project that lava could flow from its current location into the northwest part of Kaohe Homesteads within a day, and to the Pāhoa Village Road (government road) in Pāhoa within 20 days" if there are no major changes.
Seismologists predict another Icelandic volcano is about to blow
DateSeptember 15, 2014
Fairfax Science Columnist
View more articles from Peter Spinks
The red-hot fountains of molten lava, glowing like wildfire, are nothing short of spectacular. Yet they could be ominous portents of things to come.
For the second time in four nail-biting years, seismologists in the land of fire and ice, Iceland, are bracing for a monumental volcanic eruption that, once again, threatens to disrupt European air traffic.
Back in 2010, the Eyjafjallajokull volcano, which melted through 200 metres of glacier, sent more than 200 million cubic metres of fine ash billowing almost 10 kilometres into the sky. As a result, several European countries were forced to ground or re-route thousands of flights for several days.
This time the threat of an eruption – potentially even more powerful than the one in 2010 – is posed by Bardarbunga, the biggest of Iceland's 30 or so volcanic systems. Located roughly at the country's centre, the volcano's 10-kilometre caldera lies several hundred metres beneath Vatnajokull, Europe's largest glacier by volume.
Scientists are taking the latest rumblings seriously: roughly 8000 years ago, after all, the volcanic leviathan let rip with the largest eruption of the past 10,000 years.
"It is very difficult to predict exactly what will happen with an eruption," says Monash University vulcanologist Professor Ray Cas, who is president of the International Association for Volcanology and Chemistry of the Earth.