Several deep fractures and sinkholes have recently opened up in the Central Highlands near Tungnafellsjökull glacier, NE of Vatnajökull glacier. The fractures are believed to be 100-200 meter (330-660 ft) deep. The cracks were discovered by a Park Ranger who was driving a trail north of Gæsavötn lakes. Part of the road had been swallowed by the earth which had opened up.
Read more: Quick primer on Bárðarbunga, Iceland's most powerful volcano
According to geophysicists who explored the cracks earlier this month the cracks are most likely caused by changes in Bárðarbunga volcano. Páll Einarsson, one of the scientists who has studied the area told the local newspaper Morgunblaðið that Bárðarbunga and Tungnafellsjökull volcanic systems are two seperate and unconnected systems, although the very active Bárðarbunga volcano can affect the fracture system of Tungnafellsjökull. The first time we noticed changes in the fracture system of Tungnafellsjökull volcano was during the 1996 Gjálp-eruption in Bárðarbunga.
The system was surveyed again in 2009, showing new deep fractures, which suggested the systems were on the move. Since then the fractures appear to have been expanding slowly, and now we discover new sinkholes and cracks each year.
Read more: Ask the expert: Why are there so many earthquakes in Iceland
It is impossible to say with certainty what is causing the activity, but Páll argues that Bárðarbunga volcano is most likely to blame. We first discovered the cracks in connection to the Gjálp eruption in Bárðarbunga, and they deepened and expanded during the 2014-15 Holuhraun eruption. The central caldera of Bárðarbunga dropped 65 meters (213 ft) during the Holuhraun eruption as the central magma chamber was emptied. The subsiding of the caldera exerted pressure on the surrounding area, creating cracks in the rock.
Páll stresses that there is no immediate danger. Most of the cracks and sinkholes are perfectly safe, as they have already filled up with gravel and earth, but people should still avoid going into the cracks or sinkholes. The greatest danger, he pointed out, was when the cracks or sinkholes appear beneath roads, as happened earlier this summer.
According to park rangers in Vatnajökull National Park the area where the most recent cracks are visible is near Gæsavatnavegur trail in the east, west to Tómasarhagi plain in the west. The southernmost cracks are in Nýidalur valley, west of Tungnafellsjökull glacier, while the northernmost cracks are east of Mt. Fjórðungsalda.
Read more: Ask the expert: How to cross those unbridged rivers in the Central Highlands?
Some of these places are easily accessible for travelers to explore, for example 2.4 km (1.5 mi) north of the river crossing at Nýidalur cabin, and north of Gæsavatnaleið road, 3.1 km (1.9 mi) east of the junction of Sprengisandsleið and Austurleið highland routes. A parking spot has been created at this intersection for hikers. A third spot was recently discovered near the Hagakvísl river crossing, some 300 m (980 ft) downstream from the crossing.
Several deep fractures and sinkholes have recently opened up in the Central Highlands near Tungnafellsjökull glacier, NE of Vatnajökull glacier. The fractures are believed to be 100-200 meter (330-660 ft) deep. The cracks were discovered by a Park Ranger who was driving a trail north of Gæsavötn lakes. Part of the road had been swallowed by the earth which had opened up.
Read more: Quick primer on Bárðarbunga, Iceland's most powerful volcano
According to geophysicists who explored the cracks earlier this month the cracks are most likely caused by changes in Bárðarbunga volcano. Páll Einarsson, one of the scientists who has studied the area told the local newspaper Morgunblaðið that Bárðarbunga and Tungnafellsjökull volcanic systems are two seperate and unconnected systems, although the very active Bárðarbunga volcano can affect the fracture system of Tungnafellsjökull. The first time we noticed changes in the fracture system of Tungnafellsjökull volcano was during the 1996 Gjálp-eruption in Bárðarbunga.
The system was surveyed again in 2009, showing new deep fractures, which suggested the systems were on the move. Since then the fractures appear to have been expanding slowly, and now we discover new sinkholes and cracks each year.
Read more: Ask the expert: Why are there so many earthquakes in Iceland
It is impossible to say with certainty what is causing the activity, but Páll argues that Bárðarbunga volcano is most likely to blame. We first discovered the cracks in connection to the Gjálp eruption in Bárðarbunga, and they deepened and expanded during the 2014-15 Holuhraun eruption. The central caldera of Bárðarbunga dropped 65 meters (213 ft) during the Holuhraun eruption as the central magma chamber was emptied. The subsiding of the caldera exerted pressure on the surrounding area, creating cracks in the rock.
Páll stresses that there is no immediate danger. Most of the cracks and sinkholes are perfectly safe, as they have already filled up with gravel and earth, but people should still avoid going into the cracks or sinkholes. The greatest danger, he pointed out, was when the cracks or sinkholes appear beneath roads, as happened earlier this summer.
According to park rangers in Vatnajökull National Park the area where the most recent cracks are visible is near Gæsavatnavegur trail in the east, west to Tómasarhagi plain in the west. The southernmost cracks are in Nýidalur valley, west of Tungnafellsjökull glacier, while the northernmost cracks are east of Mt. Fjórðungsalda.
Read more: Ask the expert: How to cross those unbridged rivers in the Central Highlands?
Some of these places are easily accessible for travelers to explore, for example 2.4 km (1.5 mi) north of the river crossing at Nýidalur cabin, and north of Gæsavatnaleið road, 3.1 km (1.9 mi) east of the junction of Sprengisandsleið and Austurleið highland routes. A parking spot has been created at this intersection for hikers. A third spot was recently discovered near the Hagakvísl river crossing, some 300 m (980 ft) downstream from the crossing.
