Hiển thị các bài đăng có nhãn Holuhraun volcano. Hiển thị tất cả bài đăng
Hiển thị các bài đăng có nhãn Holuhraun volcano. Hiển thị tất cả bài đăng

Thứ Tư, 3 tháng 9, 2014

Up to 130 meter high lava fountains

Robust activity has been seen in the Holuhraun lava eruption this morning, says volcanologist Armann Hoskuldsson who is monitoring the event. "The highest lava fountains rise up to 130 meters from the craters," he says. The new lava field is now estimated to be 11 - 12 square kilometers in size.


"We returned to the fissure early this morning and saw considerable volcanic activity at around 7 AM," says Dr. Hoskuldsson. He and other scientists spent the night at a mountain hut nearby, after an evacuation was ordered yesterday when volcanic tremor was detected in the area, leading to fears that a subglacial eruption was imminent. "The main craters are now very active and the lava fountains from them rise up to 120 - 130 meter height," he says.


The new lava from the fissure now extends to about 11 - 12 square kilometres says dr. Hoskuldsson. "It´s been robust in the last hours and lava has been flowing westward by about 300 meters. The fissure itself has not changed much however; it´s still 1.7 - 1.8 kilometer long," he says.

Despite the volcanic tremor yesterday, no signs of a subglacial eruption have been seen, and no change has been observed in water flowing from beneath the glacier. The tremor is still unexplained, but indications point to an area south of Holuhraun, extending under the Dyngjujokull glacier margin where a small rift valley (graben) has formed. One possible theory, according to scientists, is that groundwater has seeped through deep cracks in the bedrock, down to the magma intrusion beneath, causing explosive activity detected by seismometers.


According to the Icelandic Met Office (IMO), GPS measurements indicate that the volume of magma entering the dike intrusion is still more than the volume of lava being erupted at the Holuhraun fissure. The rate of magma being pumped in seems however to have slowed , says Benedikt Ofeigsson, a geophysicist at the IMO.

Seismic activity is still ongoing at Holuhraun, but the strongest earthquakes have been detected near the rim of the Bardarbunga volcano. Four earthquakes, exceeding magnitude 4 have occurred there since midnight. The strongest one was M4,8 according to the IMO.

How to get there?

Those of you wishing to travel to the area and take a flight can contact these companies:

Flight from Reykjavík (from 670€)
- Helicopter from Reykjavík (from 1.180€)
Flight from lake Mývatn (from 250€) Most popular: Recommended
Super Jeep Tour from lake Mývatn (from 220€)
Flight from Akureyri (from 360€)
- Helicopter from Akureyri (780€)

Source: www.ruv.is
Iceland24

Chủ Nhật, 31 tháng 8, 2014

New eruption: 60 m high lava fountains

The effusive eruption in Holuhraun that started early this morning is producing 50 - 60 meter high lava fountains, according to a volcanologist at the site. The active fissure is 1500 - 1800 meter long, considerably larger than the fissure that opened Friday morning.


According to Armann Hoskuldsson, volcanologist at the University of Iceland´s Institute of Earth Sciences, who is at the site, the lava flow from the fissure is about 10-20 times more than Friday morning. The eruption is estimated to be 10 to 20 times bigger than the one Friday morning, and looks "robust" says Dr. Hoskuldsson. He says the highest lava fountains can be seen at the southern end of the fissure, but at the northern end, they are less powerful. The southern end of the fissure is about 4 kilometres north of the Dyngjujokull outlet glacier.

The Civil Protection Agency has maintained its level of preparedness at "danger", and previous road closures and area restrictions are in effect.


This effusive fissure eruption is the third one in the area since last weekend. On Aug. 23, a small subglacial eruption occurred near the Bardarbunga caldera in Vatnajokull. The eruption was shortlived, and did not break through the glacier, but did create calderas that were spotted a few days later. Early last friday, a small fissure opened in the Holuhraun lava field, north of the Dyngjujokull outlet glacer. That eruption lasted for 3 - 4 hours.

Seismic activity has been detected in the Bardarbunga region this morning, but less intense than in recent days. Today, the weather conditions are very unfavorable north of Vatnajokull, with high wind and rain forecast for today. Here is a webcam near the eruption site, but due to fog and rain, visibility is sometimes very limited.


Eldgos hófst í Holuhrauni, norðan Vatnajökuls, rétt fyrir klukkan sex í morgun. Þetta er þriðja gosið á Bárðarbungusvæðinu á rúmri viku. Gosið er hraungos, á sömu sprungu og opnaðist aðfaranótt föstudags, en gosið nú er 10-20 sinnum stærra, að sögn Ármanns Höskuldssonar eldfjallafræðings, sem skoðaði gosstöðvarnar í návígi í morgun. Hann segir að hæstu hraunstrókarnir séu allt að 50-60 metra háir, syðst á sprungunni, en mun lægri norðar. Suðurendi sprungunnar er á sama stað og aðfaranótt föstudags, um fjóra kílómetra frá sporði Dyngjujökuls.

Source: www.ruv.is
Iceland24

Thứ Sáu, 29 tháng 8, 2014

Holuhraun eruption lasted 3-4 hours

The fissure eruption in Holuhraun lava, north of Vatnajökull glacier, which started at midnight, is already over. The eruption lasted for about three or four hours, according to Páll Einarsson, professor geophysics at the University of Iceland.

"It was a small eruption and a small sample of the magma that is moving underground reached the surface," says Páll, describing the events of the night as an abberation in the larger course of events of the last two weeks.


Páll agrees with fellow professor of geophysics, Magnús Tumi Guðmundsson, who earlier today described the eruption as an "accident". "The magma intrusion strayed unnecessarily close to the surface and some magma came out," Páll says.

The Icelandic Met Office has downgraded the aviation alert over the volcanic eruption area from red to orange. There is not considered to be a risk of volcanic ash reaching the atmosphere.

The Icelandic Transport Authority has also reduced the restricted flight area around the volcanic activity from 10 nautical miles (NM) to 3 NM and 5,000 foot altitude. The warning area restricting instrument flight rules flight remains unchanged.

The eruption fissure is about 5 kilometers from the Vatnajökull glacier. The fissure appears to be about 1 kilometer long. The lava is thin and flowing quickly southeast towards the glacier.

Source: www.ruv.is
Iceland24

An small eruption in Holuhraun

A fissure eruption started around midnight in the Holuhraun lavafield, ca. 9 kilometers north of Dyngjujokull glacier. Lava streams out of a 100 meter long fissure, in the northern part of the lava field, about 15 kilometers south of the Askja caldera. IMO has issued a ONLY orange alert for aviation (there is no danger, it is a small eruption).


The eruption seems to have started near the northern end of the magma intrusion that has been propagating northward from the Bardarbunga caldera since August 16.

Small surface crevasses were seen in the Holuhraun lava field yesterday, leading to increased interest among scientists. The possibility of an eruption migrating southwards, towards the Dyngjujokull glacier cannot be excluded at this time.

Benedikt Ofeigsson, staff member at the Icelandic Met Office is at the scene. In an interview with RUV tonight, he described the eruption as small; lava is flowing to the southeast and some small tephra mantles are coming out of the fissure.


The IMO has issued a red alert (highest) for aviation. That means that airtraffic is restricted in a large area around the eruption. The fissure lies on a northeast - southwest direction.

A live webcam of the eruption can be found at www.mila.is. Road and area restrictions that have been enforced over the last days are still in effect in the area north of the Vatnajokull glacier.

The situation is not serious and is a small eruption. There is a tour company that is already offering a tour to go see the volcano.

Source: www.ruv.is
Jóhanna & Kolla
Iceland24, August 2014