Geology and geography of the Faroe Islands

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The South Island ( Suðuroy ) is particularly typical because it has all the facets of the Faroese landscape in a very small area, here the view to the north from Beinisvørð along the inaccessible west coast. Note the red-brown Tuffbänder in the mighty basalt - the cliff . Behind the isthmus you can see the gently sloping, inhabited east coast on a fjord , behind it the fjall of the interior.

The history of the geology of the Faroe Islands shows parallels to the geology of Iceland , although volcanism in the Faroe Islands has long been extinct. Geographically, the Faroe Islands are around 60 million years old.

The Faroe Islands lie on the Wyville-Thomson Ridge in the North Atlantic , which stretches from Ireland and Scotland over the Faroe Islands and Iceland to Greenland and meets the Mid-Atlantic Ridge near Iceland .

Tertiary

Typical layer structure of the Faroe Islands: thick basalt, thin tuff, basalt on top , and so on ... At Í Fámara on Suðuroy.

In the Tertiary (60 to 70 million years ago) volcanic activity created a huge plateau on the Wyville-Thomson Ridge that was about 3,000 to 4,000 meters high.

The typical Faroese basalt was created from the cooled lava , which is repeatedly criss-crossed by thinner layers of tuff , which arose from the subsequent ash rain, which cooled and was pressed together. Each of the three to ten meters, sometimes up to 30 meters thick basalt layers are evidence of a volcanic eruption. The softer tuff layers in between are much thinner.

During a volcanic break there was tropical vegetation. Coal layers on Suðuroy and Mykines show imprints of the primeval sequoia and ginkgo .

River beds emerged and looked for their cheapest route through cracks in the rock, where over time they formed deep ravines , so-called V-valleys . Since the plateau sloped slightly from northwest to southeast, most of the rivers also ran in this direction. The surf of the Atlantic attacked the plateau on its coast. The soft tuff layers were unable to cope with this violence, were washed away and caused the thick basalt layers to collapse above them. This resulted in huge demolition edges, mainly on the west and north coast.

As a result of this erosion , most of this plateau subsided. What remained were the islands of the Hebrides , Faroe Islands and Iceland , with Iceland only being formed around 20 million years ago and still volcanically active today due to its location on the Mid-Atlantic Ridge, while the basalts of the British Isles, for example the Giant's Causeway , compared to those of the Faroe Islands are comparatively modest.

Apart from the rock formations, only one thermal spring , Varmakelda near Fuglafjørður on Eysturoy, at around 20 ° C, testifies to the volcanic activity on the Faroe Islands .

The Faroe Islands photographed from space. The other photos in this article are from the southernmost island of Suðuroy.

Ice age

The Ice Ages divide the Quaternary , which began about 2.4 million years ago. The Ice Age glaciers, which covered the entire island during the Ice Ages, formed the Faroe Islands in their present form from the remains of this plateau. The glaciers ( jøklar , singular jøkul ) hiked the natural path along the inclined plane to the southeast and formed a connection from the existing gorges ( gjáir , singular gjógv ) the characteristic trough valleys ( dalir , singular dalur ), which often filled with water created with the sea and form today's straits and fjords of the Faroe Islands . The largest lake in the Faroe Islands, Sørvágsvatn , would almost have become a fjord ( fjørður ), but 32 meters above sea level separate it.

The Faroe Islands owe their present form to the Ice Ages. It is characteristic that the islands of the Faroe Islands almost all extend in a southeast-northwest direction, corresponding to the sound between them and the sometimes long fjords, which often make the viewer doubt whether the opposite piece of land is a neighboring island or just the other bank of the fjord .

A steep basalt step like on this step-shaped slope is called hamar in Faroese . The flatter terrain in between is called rók . Hamrabyrgi on Suðuroy is not called that for nothing.

East coast and inland

Today we see semicircular cirques where the glaciers originated , which the Faroese call botnur . Often the fjord ends are what place names like Kaldbaksbotnur remind of. Shallow sandy beaches sometimes form in the bays, such as in Tjørnuvík , which is in such a valley (and therefore mostly in the shade).

The longest trough valley (U valley) on the Faroe Islands is the 11 kilometer long valley between Saksun and Hvalvík , the Saksundalur . Here, as in other places everywhere in the interior and on the east coast, the typical staircase structures of the slopes, which the glaciers have formed from the basalt and the tuff layers, can be seen. Such a step is called hamar on its vertical side in Faroese , hence the place name Hamrabyrgi , for example . The flatter, grassy slopes between the hamrar are called rók (Pl. Røkur ). They formed out of the weathered tuff. More debris accumulates at the foot of each hamar. Streams ( áir , singular á ) plunge down here as a waterfall ( fossur ).

Víkarbyrgi / Hamrabyrgi on the - by Faroese standards - flat east coast of Suðuroy in total. Although actually conveniently located, only sheep live here today. The staircase structure of the mountain and the bay are typical of this Faroese landscape.

A mountain slope on the east coast and inland can thus have various steps, where - having arrived at your foot - you can often no longer see the summit, but work your way up from floor to floor. At around 300 meters, another vegetation begins, at around 600 meters it is arctic-alpine. The average temperature decreases by ½ ° C every 100 meters. This is not the only reason why all Faroese live below 100 meters on the fish-rich coast. Down here in the fjords and bays it is more sheltered from the wind and agriculture can be thought of in general. The higher elevations are reserved for the 70,000 sheep as pasture.

The highest mountains in the Faroe Islands still bear witness to the former plateau . They are often table mountains . For example, the highest mountain in the archipelago, Slættaratindur (882 m), hence its name flat peaks . It drops relatively flat (not vertically) into the Atlantic to the north and is therefore the highest of its kind in Europe, rising directly from the sea.

Many other mountains are ridges that sometimes form entire islands such as Kalsoy and Kunoy . At their ends they look pyramidal . In the interior of the country, such a ridge often follows, interrupted by one trough valley, onto the next. If the valley is below sea ​​level , it is a fjord or a sound.

The climate in the Faroe Islands ensures that none of the peaks is covered by snow in summer. This can only hold in a few small, always shady places.

A mountain inland is called fjall [ fjadl ] (Pl. Fjøll ) in Faroese . This means exactly the same as in Norway with Fjell . Accordingly, the mountain landscape itself is called Fjall.

At 469 meters, Beinisvørð is by far not the highest promontory on the Faroese coast - but perhaps the most beautiful.

Steep coast, stiles and cliffs

The cliffs or cliffs of the Faroe Islands are among the highest in the world. Often the Cape Enniberg (754 meters) in the far north of the archipelago on Viðoy is considered to be the highest sea cliff in the world, others are more modest and call it the highest in Europe. It is important to consider what you are talking about: a steep slope or a vertical wall. Enniberg is vertical. If vertical is not the criterion, then the Kunoyarnakkur (819 m) at the northern tip of Kunoy is again one of the highest capes in the world. Vertical walls several hundred meters high are mostly found on the west and north coasts of the islands. They form the famous bird mountains ( fuglabjørg , singular fuglaberg ) as nesting sites for the Faroese seabirds . In Faroese a distinction is made between fjall and mountain . A mountain is always a cliff.

The Baglhólmur on the east coast of Suðuroy in the foreground. Left behind the opposite bank of the fjord. Behind a steep coast of the same island. In the very right center of the picture a solitary table mountain , the island Lítla Dímun ; behind to the left Stóra Dímun in a similar shape. Visibility: About 40 kilometers to the south coast of Sandoy on the horizon.
A drangur is a free-standing column without a flat top.

This coast is still constantly exposed to the surf, which can be up to 50 meters high, and the violent winter storms. There are grottos everywhere in the rock that the sea has washed away . If the surf hits such a cavity, high air pressure is created , which is partly responsible for parts being blasted out of the rock. Therefore, the coast is not only criss-crossed by vertical crevices, but is also provided with free-standing cliffs immediately in front of it . Such a column is called staccurate when it is blunt and drangur when it tapers to a point. Sheep can also graze on a large stake.

There are also Holme off the coast . A Holm ( hólmur ) is a small island ( oyggj ), which is not counted among the 18 islands of the Faroe Islands. And finally there are small, shallow archipelagos , which are not overgrown by grass, but z. B. serve the gray seals as a refuge.

Word lists of geological expressions