Thursday, 28 August 2014

Magnitude 5.0 Earthquake beneath the Vatnajökull Glacier, Iceland.

The Icelandic Met Office recorded a Magnitude 5.0 Earthquake at a depth of 3 km beneath the Vatnajökull Glacier slightly before 8.15 am GMT on Thursday 28 August 2014. The event occurred about 7 km to the east of the Bárðarbunga Volcano, which has been going through an active period this month, and the two events are likely to be connected, although an event of this magnitude would be exceptionally large for a volcanic Earthquake. Magnitude 5.0 Earthquakes are potentially quite dangerous, but the remote location of this event makes it highly unlikely that there were any casualties.

The approximate location of the 28 August 2014 Vatnajökull Earthquake. Google Maps.

Seismic activity beneath volcanoes can be significant, as they are often caused by the arrival of fresh magma, which may indicate that a volcano is about to undergo an eruptive episode. Bárðarbunga last erupted in about 1862, and has undergone several periods of raised seismic activity since then, most recently in 1996 and 2010. The last month has seen a strong increase in seismic activity around Bárðarbunga, but as yet there is no sign of any eruptive activity at the surface. 

Iceland lies directly upon the Mid-Atlantic Ridge, a chain of (mostly) submerged volcanoes running the length of the Atlantic Ocean along which the ocean is splitting apart, with new material forming at the fringes of the North American and European Plates beneath the sea (or, in Iceland, above it). The Atlantic is spreading at an average rate of 25 mm per year, with new seafloor being produced along the rift volcanically, i.e. by basaltic magma erupting from below. The ridge itself takes the form of a chain of volcanic mountains running the length of the ocean, fed by the upwelling of magma beneath the diverging plates. In places this produces volcanic activity above the waves, in the Azores, on Iceland and on Jan Mayen Island.

The passage of the Mid-Atlantic Ridge beneath Iceland. NOAA National Geophysical Data Center.

See also...

Iceland has evacuated around 300 people from the area around the...

The United States Geological Survey recorded a Magnitude 4.8 Earthquake at a depth of 10.3 km roughly 8 km south of the...

The Icelandic Meteorological Office are reporting a series of steam explosions took place on Mount Kverkfjöll on the southeast of the Island on Thursday 15 August 2013. The explosions apparently occurred after increased glacier melting due to warm weather caused water levels in the Volga river to rise, causing water to enter a...

Follow Sciency Thoughts on Facebook.

No comments:

Post a comment