Lost Limbs Foundation

Wednesday, May 22, 2013

Fire Giant Hekla


Fire giant Hekla

In Norse worldview the ice, snow and arctic winds of Iceland were seen as evil giants. Thus Iceland was known as Jötunheimr, land of the giants. Jötunheimr in turn was one of the nine homeworlds joined by the world tree Yggdrasill. Several other geological features of the Icelandic landscape also have a mythological meaning. For example, Hekla one of Iceland’s most active volcanoes which was seen as the fire giant Surtr also known as the giant with the flaming sword. When Hekla threw its eternal fires high into the southern skies it became Surtr and once he moved he set the world aflame. In modern day Iceland Surtr is still seen as a giant of fire. The volcanic island of Surtsey which emerged out of the ocean in 1963 was even named after him. The name Hekla comes from the old Norse word for cloak since it’s summit is often hidden in a cloak of mist.

In the later middle ages Hekla (and volcanoes in general) was infamously known ...
Continue Reading
Fire giant Hekla

In Norse worldview the ice, snow and arctic winds of Iceland were seen as evil giants. Thus Iceland was known as Jötunheimr, land of the giants. Jötunheimr in turn was one of the nine homeworlds joined by the world tree Yggdrasill. Several other geological features of the Icelandic landscape also have a mythological meaning. For example, Hekla one of Iceland’s most active volcanoes which was seen as the fire giant Surtr also known as the giant with the flaming sword. When Hekla threw its eternal fires high into the southern skies it became Surtr and once he moved he set the world aflame. In modern day Iceland Surtr is still seen as a giant of fire. The volcanic island of Surtsey which emerged out of the ocean in 1963 was even named after him. The name Hekla comes from the old Norse word for cloak since it’s summit is often hidden in a cloak of mist.

In the later middle ages Hekla (and volcanoes in general) was infamously known as a one of the gateways to the underworld together with Stromboli in Italy. This was mostly due to Hekla’s smoky summit, steep ridges covered with black lava flows, its ability for destruction and ravens (which were thought to be the souls of the dead) encircling the mountain. The devastating 1104 AD eruption which buried half of Iceland in a layer of ash and tephra could also have something to do with it. Accordingly, this eruption was a VEI 5 (Volcanic Explosivity Index, see here for a definition: http://on.doi.gov/12Jo4s7) which is defined as very large. Thus the effect on the population and livestock must have been devastating.

German physician Caspar Peucer wrote that during great battles miserable cries and moaning came out of the bottomless abyss of Hekla and vultures and ravens build their nests on the flanks. Hissing lava bombs (due to the cooler temperature of the air colliding with the superhot lava bomb) emitted from the crater during eruptions were seen as souls screaming in agony. A 17th century travel guide by Frenchman de la Martiniere mentions that the devil would torture the souls of sinners by dragging them out of the crater of Hekla and dipping them in the freezing ocean. Cistercian monks claimed that if the world knew sacred places and churches, then an icy mountain which spewed fire should be seen as the opposite, hell. It was not until the 1800s that this belief lost ground. Presently there is still a legend that Hekla is a meeting point for witches.

Since Iceland was settled by Norsemen Hekla had about 20 eruptions. As a volcano Hekla is quite hard to define. It’s characteristics lie in between a fissure volcano and a stratovolcano. During eruptions Hekla can throw up either basaltic or andesitic magma in fissure eruptions or explosive silicic eruptions. Explosive eruptions could transform into lava fountains which in turn transform into fast flowing lava flows. The tephra that Hekla emits is high in fluorine which can be hazardous to grazing animals. Also eruptions can go on or short periods of time (days to weeks) to months or years.

Hekla is currently being monitored by volumetric borehole strainmeters (these measure changes in the volume of a magma chamber), SIL stations (seismometers which record motion of the ground) and GPS stations (which measure uplift of the ground which could indicate the magma chamber is filling up). In the end of March of 2013 shallow earthquake swarms were measured at Hekla indicating that magma was possibly on the move. In April rapid inflation was measured on the northern flanks of the volcano. Yet, since then the activity has stagnated. It is evident nevertheless that in the future this fire giant will erupt again.

--BO

Image: Copyright Michel Detay. Hekla during an eruption in 1980.

References and further reading:

http://volcanocafe.wordpress.com/category/europe/iceland/hekla/

http://www.volcanodiscovery.com/nl/hekla.html

http://www.volcano.si.edu/volcano.cfm?vnum=1702-07%3D

http://volcano.oregonstate.edu/book/export/html/1015

Boult Katherine. 1916. Asgard and the Norse heroes.

Zeilinga de Boer Jelle & Donald Sanders. 2002. Volcanoes in Human History: The Far-Reaching Effects of Major Eruptions