Approximately every four or five years Iceland experiences a volcanic eruption. The country is situated on the Mid- Atlantic ridge, the joint between the Eurasian tectonic plate and its North American counterpart. This particular plate boundary is of the divergent type, meaning that the two opposing plates are moving apart, creating new crust when magma from the earth‘s mantle escapes upward through the voids created. The plates drift to the west and east respectively, as shown in the accompanying drawing. This movement adds about 2-3 cm to the country’s width annually so slowly but surely we are coming to your neighbourhood. Locations of some of the larger active volcanoes within Iceland are depicted as red triangles, and as can be seen these line up along the plates’ boundary.
As it is almost impossible to describe the majesty of a volcanic eruption I am going to show you some photos of the most recent such occurrences, the first from the Krafla eruptions of 1980 (here beside) and 1984 (here below). Krafla is a crater row formation (caldera) in the north of the country which erupted 5 times between 1975 and 1984 but has been passive since. Considering that Krafla had lain dormant since 1729 when it began this active stage in 1975, we probably won’t be hearing from her again anytime soon.
The next photos are from Hekla – the reigning volcano queen which has erupted every ten years since 1970 (1970, 1980, 1981, 1991 and 2000). As seen from this series anything could happen in this year 2011, i.e. if the repose period has not changed. Before this, Hekla erupted every 50 years and is classified as one of the most historically active volcanoes of the world. Hekla eruptions are explosive, soaring plumes stretch to the heavens and this is followed by lava fountains and extensive lava flows. It is shaped the way a kid would draw a volcano (stratovolcano) but is in fact more as it is also a crater row. Some Hekla eruptions have caused great damage, the eruptions of 1510, 1694 and 1766 in particular. The photo here below is the oldest photograph taken of a Hekla eruption and dates from 1947. The photo below that and the one to the left are both from the eruption in 2000.
If Hekla bears the volcano queen crown you can be sure that her friend Katla is not Miss Congeniality. Katla is hidden underneath a glacial icecap but this does not stop her from adversely affecting her surrounds when the mood strikes her. Katla’s repose period is 50 years and is now overdue although since settlement this period cannot be considered reliable as is known to vary from 7 years to 80. The last confirmed eruption occurred in 1918 (see photo beside paragraph) so it has been 93 years since Katla has blown her top and every single geologist here is certain an eruption is imminent and that we can expect some attention grabbing shortly.
Now the newsworthy titbit I intended to let you in on is that as of this past weekend we now have a full-blown eruption on our hands – in Fimmvörðuháls in south Iceland. The eruption is of the type we call a tourist eruption – something for the eye, close enough to Reykjavík for a day trip, but far enough away from urban areas to be semi-safe. At the moment it is closed off for the public but this will probably change in a matter of days and organised trips to the areas scheduled. If so I am sure to be on one as soon as I can get my hands on a ticket although there is no rush as the eruption is believed to continue for weeks or months.
This particular eruption is beautiful to behold, a curtain of red and orange lava fountains that are so surreal that they almost seem organised by a Las Vegas hotel designer. The flowing lava pours off a cliff into a canyon 200 m below – the highest “lavafall” in the world. The photos I have added do not do video clips shown on the news justice, and further to this neither does video do the in-situ experience justice. The trembling ground accompanying an eruption, the incredible noise, the heat and the smell of sulphur add depth possibly attainable in a 1980-s movie theatre equipped with shaking chairs and only if the footage were directed by John Waters using his Smell-o-Vision concept. As this is unlikely to happen I am going to insert a clip from youtube showing the eruption although the one I would have wanted to show you has not reached the site yet, unfortunately. This one is taken pretty early so the lava flow has not begun to any extent, nor has the accumulation of ash and pumice now surrounding the crater row. Hopefully I will have managed to find the clip from today's news in some usable format and set it up for next week.
In my next post I am going to tell you about the Heimaey eruption of 1973 which deserves its own seperate discussion. It is the premise of my third Thora novel (Ashes to Dust) and having done a lot of background work in preparation I know the event quire well, not to mention the various stories the people who lived through the catastrophe. Unlike Katla, Hekla, Laki and Krafla - Eldfell in Heimaey erupted in the outskirts of an inhabited town.
Yrsa - Wednesday