Siim

Maar

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Crater lake in Iceland
Viti maar in Iceland is associated with Krafla volcano near Lake Myvatn area. White matter in the foreground is snow. Snow is common in Iceland even during summer months. Two people on the opposite rim for scale.

Maar is a specific type of volcanic crater. They are created by powerful volcanic explosions which almost instantly create a circular hole which is later filled with groundwater. Groundwater is a very important component in this process as it is the reaction between rising hot magma and groundwater that gives so much explosive power to this process. Such a volcanic eruption is known as phreatomagmatic eruption. Created hole fills with water and becomes a crater lake.

Viti maar in northwestern Iceland is a superb location for hiking and photographing. This maar is geologically very young, dating from 1724.

Sea urchin and sea bluebells

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Oysterleaf and sea urchin on a rocky coast in Iceland
Oysterleaf and sea urchin.

Beaches are always interesting, especially if you are into natural sciences. Iceland is no exception. Today I want to demonstrate a combination of a sea urchin shell with a beautiful nordic plant called sea bluebells or oysterleaf that commonly grows on rocky coasts.

I have mentioned sea urchins several times before because their colorful spines often end up being sand grains. I found one fellow with lots of its spines still attached but I will leave it for another day.

This sea urchin is one of so-called green sea urchins because most of its spines are green. Its latin name is Strongylocentrotus droebachiensis. It is common in cold arctic oceans. The plant next to it is Mertensia maritima. It grows even in Svalbard and Greenland and seems to feel quite comfortable in Iceland.

Mudcracks in Gran Canaria

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mudcracks
Mudcracks near Agaete in Gran Canaria, Spain.

Mudcracks are very common phenomena but in most cases barely worth photographing. Last december when I was in Gran Canaria I spotted larger area near the sea that was full of nicely formed mud polygons.

The formation of mudcracks probably needs no explanation. They are desiccation cracks which means that they form when wet fine-grained sediment loses its water content and contracts. Mudcracks are common in dry muddy areas which are subject to occasional flooding. In this particular case it was most likely seawater that inundated fine-grained sediments behind coastal pebble bar that now separates it from the ocean.

White storks at sunset

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White storks on a nest
White storks on a nest.

Pair of white storks (Ciconia ciconia) are living next to my summer home. They had no chicks last year but this season they are more lucky with two fast growing young ones. I took this picture almost a month ago before going to Iceland. Now they are much bigger, almost the size of an adult stork but their beaks are still black. It will turn red later when they are fully adult.

They should be soon ready to attempt flying for the first time. I once as a child had an opportunity to see the first flying attempts of storks. It is quite easy to watch them as they are abundant in Estonia and often live close to people’s homes. As you can see they also prefer electric pylons. It must be a great view for them, especially at sunsets.

Waterfall like a mini Iceland

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Upper cascade of Gullfoss waterfall in Iceland
Upper cascade of Gullfoss waterfall in Iceland.

This image has several elements that are present in Icelandic nature. Waterfalls are abundant there, sky is often threatening and weather less than pleasant. And Iceland demonstrates in many ways energy and power just like this cascade which forms the upper part of the famous Gullfoss waterfall.

Invasive for sure but beautiful nevertheless

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One beautiful flowering plant seems to really like Iceland. It is a lupine species Lupinus nootkatensis, more commonly known as Alaskan lupine or Nootka lupine. Its beautiful dark blue flowers fit well with Icelandic wet and cool weather which casts cold hue to the landscape there.

However, it is obvious that it is an invasive species there. Why obvious? Because it is widespread where most people live in SW and southern parts of Iceland but almost absent in eastern and northern parts of the country. And it is especially common by the roads which is another clear indication that we are dealing with an invader here.

I read a bit about this plant because its story started to interest me. It turns out that it was introduced to Iceland in 1945 to combat soil erosion and to add nitrogen to the soil. It is so successful because sheep do not want to eat it because it contains bitter tasting alkaloids. So it spreads each year even more and threatens native species in Iceland because lupine is much taller than most native plant species and creates a canopy over them which blocks sunlight.

As I can understand it is a controversial issue for many Icelanders. Introduction of aggressive invasive species are nowadays almost universally considered to be a tragic mistake. However, in this case the story is more complicated because Icelandic landscape seems to benefit from its presence. This, of course, is just a matter of taste.

Close-up of Nootka lupines growing in Iceland
Nootka or Alaskan lupines growing in Iceland.

Field of Nootka lupines in Iceland
Field of Nootka lupines. They are really abundant and often occupy large fields.

Nootka lupine in Iceland
Nootka lupines in the foreground.

Boundary between Europe and America

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Thingvellir mid-ocean ridge
Boundary between Europe (on the left) and America at Thingvellir.

Thingvellir (correct spelling is Þingvellir but I am afraid lots of people can not properly see this letter) is a must visit location for all geologists visiting Iceland and it is one of the Icelandic geological landmarks which is visited by many tourists who are not particularly interested in geology. Mainly because it is close to Reykjavik — the capital and most populous town in Iceland and also because it is truly remarkable to see so well displayed boundary of two major tectonic plates and last but not least this is the original location of the oldest parliament in the world — The Althingi.

I took this picture few kilometers away from the point visited by most tourists. I think it shows the graben bounded by normal faults even better and I also managed to avoid hordes of tourists who would otherwise place themselves on every photo I take.

What next for Sandatlas?

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I have not found time to update this blog for some time. It will continue to be that way at least for the next few weeks when I will be in Iceland. Hopefully it will be a very interesting trip. I plan to see lots of geology which should not be difficult because Iceland is one of the most spectacular geological hotspots on this planet.

I also have to think about the future of Sandatlas. I’ve been doing so during the past few weeks but I have not decided anything. I feel that it does not make much sense to continue as before. Blogging is interesting but consumes lots of time which should probably be invested elsewhere. I will also most likely continue my geology studies as a PhD student. It means that I have even more geological stories to tell but unfortunately less time to do that.

One possible way to keep going is to change the general character of Sandatlas. Maybe I should write it mostly as a photo blog. I do take lots of geological photos and like to travel. I have therefore no shortage of material but have less and less time to write lengthy posts. Maybe a blog post consisting of one or two photos and few explaining sentences is a solution? We’ll see.

The Little Mermaid: an alternative perspective

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The statue of The Little Mermaid (Den lille havfrue) is an iconic symbol of Copenhagen. Not many tourists visit the capital of Denmark without paying a visit to her. So did I few days ago. It was my first visit to Copenhagen. I was there with my wife and children. Copenhagen was one stop of our tour of Nordic countries which also involved visits to Åland and southern Sweden. This trip was not planned to be geological but geology is almost everywhere. So I think I also managed to collect material for a couple of blog posts.

The Little Mermaid seems to be very remotely connected to geology, if at all. However, I noticed that interestingly the mermaid sits on a foundation of several boulders which all seem to have a different lithology. I can not be sure because obviously I could not sample these rocks. I only saw them from a distance of several meters but my guess is that the mermaid is sitting on a granitic boulder. Below that is a light-colored and layered sandstone or quartzite. On the left from sandstone is a migmatitic boulder. In front of them seems to be a gabbro. And the dark-colored boulder on the lower right could be amphibolite.

http://picasaweb.google.com/107509377372007544953/Chert#5884941370792755986
The Little Mermaid and geology beneath her.
http://picasaweb.google.com/107509377372007544953/Chert#5884941368995666370
Five rocks, all of them different. I don’t know whether it is intentional or just happened that way but The Little Mermaid statue provides something even for die hard geologists.

New beginning

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Flowing lava means destruction to settlements in its path and death to vegetation and all other living forms. It leaves behind barren and desolate landscape which for me and undoubtedly to many others is very beautiful and fascinating in its own right. Lava is powerful in the short run and usually unstoppable but eventually living nature wins and conquers it again.

It is amazing how tiny plants start growing on a surface which seems to be a bare rock without any soil cover:

http://picasaweb.google.com/107509377372007544953/Hawaii#5879041477144903954

These small ferns grow on a basaltic pahoehoe lava which is perhaps only ten years old. It is difficult at first for sure but plants are tough and will persevere and it gets easier with every new generation because there already is a small amount of soil to grow on. It may take some time (perhaps only few hundred years in Hawaiian climate or even less) but eventually we would not recognize the landscape because it looks something like this:

http://picasaweb.google.com/107509377372007544953/Hawaii#5879041480561518466

It is funny to me to see ferns as big as these. These plants are common where I live in northern Europe but they are small. It almost seemed that I somehow time-travelled to a Mesozoic forest and would soon meet dinosaurs as well.