A couple of weeks ago I drove down to Unstad in Lofoten for a few days to visit friends and surf. Lofoten is an archipelago west of Northern-Norway, about 6 hours’ drive south of Tromsø, known for its stunning scenery with whitewashed beaches and mountains rising dramatically straight from the sea. Unstad is one of the three top spots in Norway for surfing. Absence of waves, however, led us to hike mountains instead.
It was one of those windy days. In the evening, however, the wind settled and the sun came out through dense clouds. We started hiking Himmeltindan in Vestvågøy, known as one of Lofoten most popular hikes, and Vestvågøy`s highest peak. On the way up, one of my friends told me he heard that Lofoten was one of the oldest mountain chains in the world. This was a very interesting “rumor” coming from a non-geologist I thought. I was not aware of it, so it excited me, and I become eager to read more about the origin of Lofoten. Having a little bit of social integrity, however, I knew I had to wait until I came down from the mountain to do so (even though I wanted to; In fact, I always intend to read a little about the geology of the mountains that I am hiking before the hike, but I always forget to!). Anyways, I started to speculate instead. I thought, if true, the mountain-chain must have had been there well before the Scandinavian Caledonians, which you can read more about here. Shortly, the Scandinavian Caledonians is the mountain chain that runs through Scandinavia, originating form the Caledonian mountain building event for about 485 million years ago, when Greenland and North-America crashed into Norway. Earth is 4600 million years old, and the oldest rocks found on earth are discussed between 3800 to 4000 million years. Since then, the continents have split and re-gathered in several cycles of supercontinents. Putting it in hopefully clearer perspective, these old rocks still present on earth, have kind of survived several wars of Plate Tectonics. The mountain chain of Lofoten could potentially be remains of, as far as known by mankind, the world`s first supercontinent – Columbia, or, even originate from before that. I knew it most likely was the igneous rocktype granite; since Lofoten consist of mostly that rock-type. I was now eager to find out (if, or) what type of granite Himmeltindan consisted of, and what likely several thousand million years of exposure had done to the rock.
After a while of “intense” hiking to catch up with two friends that had started a little earlier, we slowed down the pace and I was able to study the rocks we went past. I grabbed a white-ish rock I found on the ground and studied it, that seemed representable to the mountain itself. As far as I can remember, I have not seen a similar type of granite before. It had large crystals, was very white and seemed to consist of Quartz, Calcite, and something darker, a rather strange combination! Another interesting sight on the way up was a rock that looked like a surf-wave (see picture)! It looked like it was eroded/teared down by waves or running water, a common process that often happen softer rock-types as sandstone or calcite (, for example as in this picture). I guess, on a longer time-scale, such erosion can also happen to harder rocks, this being the results of that.
The hike itself was beautiful in the everlasting midnight sun, dancing low on the horizon. After about 3 hours, the last hour in wet-snow, we reached the top. It was truly worth it! The name Himmeltindan (“peaks of the sky”) met its expectations. I believe we could see most of Lofoten from there, and also all the way to the mainland, all surrounded by the Norwegian Sea. We run and stumbled back down with rocks in our pockets. At least one of us did.
At 01:30 (while the sun still shined, obviously), we drove home to the little cabin of my friends to make burgers and have an after-hike beer. At 04:00 we went to bed, really just because it was so late/early. As many others, I find it very hard going to bed during this time of year. Imagine, it is so nice and warm that sunscreen is necessary even during nighttime. You sort of just want to keep on with the day, and sleep during rainy days.
It is time to stop going on about my day and get to the facts. After some research, it turned out my friend was right! Lofoten archipelago consists mainly of Paleoproterozoic rocks such as tonalitic gneisses and Greenstone belts, typically older than 2500 million years. These rocks were intruded by plutons (fossil magma chambers) about 1800 million years ago, – now occupying more than 50 % of Lofoten Islands. Himmeltinden and surrounding areas show example of this. The plutonic rock-type is called Quartz Monzonite, and is, according to literature, a relatively uncommon rock-type. More specifically, like Granite, Quartz monzonite also consist of quartz and two types of feldspar (orthoclase and plagioclase feldspars). Compared to Granite, however, it contains much less quartz (5-20 %). More common examples of plutonic rock-types around Lofoten from same time is Charnokites and Mangerite.
While realizing that Lofoten really is, one of Norway`s great grand-fathers, which survived at least three plate-tectonic wars, I leave the archipelago this time with a little more respect and pride towards the stunning place.
Have a nice and stunning summer, readers!
Thanks to Myrtille Heissat for pictures.