Katla Rumbles…

Katla fissure vents are part of the larger Eldgja system in Iceland.

Fissures are elongated fractures or cracks that typically produce liquid flows.  In fact, the eruption at Eldgja in ~935 AD lasted 3-8 years and produced 19.6 cubic km of lava, making it the largest basaltic flood lava eruption in historic time.

On July 9th of this year, Katla began of a new period of unrest, triggering significant glacial melt and flooding – washing away a bridge that severed a main highway isolating parts of the island for days.   There has also been renewed seismic activity.   In just the past month, there has been more than 500 tremors in and around the caldera of Katla.

Seismic Monitoring in Iceland

A screen capture of Iceland seismic activity on 12/02

You can monitor regional seismic activity yourself at the Physics Department of the Icelandic Meteorological Office.

According to Professor Pall Einarsson from the Iceland University Institute of Earth Sciences, “The possibility that it may include a larger eruption cannot be excluded.  Katla is a very active and versatile volcano with a long history of large eruptions, some of which have caused considerable damage”

The 2010 eruption of Iceland’s Eyjafjallajokull volcano, disrupted air travel all over Europe.   However, that is very small compared to the potential of this volcanic area.   In 1783 the Laki portion of the fissure chain erupted continuously for eight months generating so much ash, hydrogen fluoride and sulphur dioxide that it killed one in five Icelanders (mostly due to famine) and half of the country’s livestock (from eating contaminated grass)!  This eruption also changed the climate of the entire planet including lowering the average winter temperature in the US by nearly 5 degrees C below the 225 year average!

You can learn more about the effects of this eruption on VW!

However, I wouldn’t panic just yet… Predicting volcanic eruptions and their potential impact is anything but an exact science and experts are unsure what to make of the current activity.  Professor Einarsson explains, “You might be on edge for some reason because the signs are strange or unusual, but it’s not always very certain what you are looking at. We have had alarms about Katla several times.”   It could rumble along without a major eruption for a very long time…

Katla straddles two spreading tectonic plates and is literally ripping itself apart.   It is the only place on Earth where the Mid-Atlantic Ridge rises above the ocean.  There have been over 80 papers related to Katla volcanic activity published in the past year.   Click here to learn more about this amazing area!

About these ads
This entry was posted in News and tagged , . Bookmark the permalink.

3 Responses to Katla Rumbles…

  1. Johan says:

    Wonderful! Just found your site and at the moment I´m having breakfast and reading this with great interest! Keep up your good work and thanks

    J

  2. Can Katla be heard from widnes cheshire egland when erupting

    • Seems unlikely for a few reasons but most obvious is ~1500 km is just a large distance… Sound follows the inverse square law, which means that every time you double the distance, the sound energy goes down 4x – there are a few other variables to take into account, but I’m sure that if you calculated out the sound energy needed to be heard that far away, it would be so loud that everyone in Iceland would be deaf. (I haven’t done the calculation, but it’s a great exercise if anyone wants to crunch the numbers)

      Known eruptions at Katla range from VEI3 to VEI6 (for more info on the VEI see http://en.wikipedia.org/wiki/Volcanic_Explosivity_Index). Krakatoa was a VEI 6 and the sound from its 1883 eruption is one of the loudest ever known. The explosion from Krakatoa was heard in Perth, Australia which is over 3000 km away!!! So… I guess I can’t say it’s impossible…

      However, Katla is part of the Eldgja Fissure System and erupts low viscosity basaltic magma. (Because Iceland is part of the Mid-Atlantic Ridge, it is the one of the most active fissure systems in the world) Since this would clearly impact the pressure and ultimately the sound pressure created by an eruption, I’m still voting no on this question.

Questions or Comments?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s