Wednesday, October 16, 2019

Iceland's Hekla Volcano is Stirring

From The Reykjavik Grapevine, October 9:

Hekla Rumbles, Authorities Alerted
Six tremors were recorded around the volcano Hekla last night, RÚV reports. While the tremors themselves were not particularly strong, an unusual amount of tremors in a very short amount of time raised reasonable concern.

As can be seen in a map of tremors in the region from the Icelandic Met Office, there was noticeable activity around Hekla last night. These tremors were all fairly small, measuring a magnitude of around 1 or 1.5....MORE
There's no immediate risk of an eruption but Hekla does have some history.

From Discover Magazine's The Crux blog, July 26:

These 4 Ancient Apocalypses Changed the Course of Civilization

Hekla Eruption 
The eruption of the Icelandic volcano Hekla may have led to the collapse of multiple thriving Bronze Age societies. 
(Credit: Abraham Ortelius/Wikimedia Commons)
Life, as they say, goes on. Until one day it doesn’t. For ancient societies, without the means to predict natural disasters, destruction could often come suddenly and completely by surprise. Below are four of the most devastating natural events in recorded human history, and the societies that they wiped off the map. 

The Storegga Slides
Until about 8,000 years ago, the British Isles were a peninsula, joined to mainland Europe by a strip of chalk downs, swamps, lakes and wooded hills. Today, we call this submerged world Doggerland.
Today, fishermen routinely bring up carved bone and antler tools from the Mesolithic hunter-gatherers who lived here. But by the end of the 7th millennium BC, a warming world caused sea levels to rise. The people of Doggerland must have watched with dread as their villages were swallowed up one by one. But one event would turn the slow advance of the sea into an apocalyptic terror.

The edge of the Norwegian continental shelf is an underwater cliff that runs for six hundred miles along the Atlantic Basin. And one autumn day around 6225–6170 BCE, this cliff collapsed. An estimated 770 cubic miles, or over 50 Mount Everests, of rock broke off and slid into the deep ocean.

The rubble flow reached a speed of 90 mph underwater. 
Doggerland Map
A map showing the extent of Doggerland, along with the location of the Storegga slides.(Credit: Francis Lima/Wikimedia)
Meanwhile, on the surface, the ocean bent into a tsunami of unimaginable force. The waves may have reached initial heights of 260 feet, striking the Norwegian coast with 130 foot breakers, and Scotland with waves 65 feet high....
....MUCH MORE, including the Hekla story.

We had some mentions of Hekla (and big sister Katla) when Eyjafjallajökull was exploding back in 2010 and have some ideas on how to trade a big eruption should the occasion arise.

Spectacular: Lightning streaks across the sky as lava flows from a volcano in Eyjafjallajokul  
Spectacular: Lightning streaks across the sky as lava flows from a volcano in Eyjafjallajokul (More via the Daily Mail)