Fennoscandia is a geologically and culturally connected area in Northern Europe. The bedrock of Fennoscandia lies under the Baltic sea, Finland, Sweden, Norway and Denmark, and Karelia (which is under Russian rule). Often confused with the peninsula of Scandinavia, which includes only Sweden and Norway.
The mountain range of the Scandinavian peninsula shields the inland behind it from the Atlantic ocean and the Barents sea in the north. The Scandinavian mountains are higher in the south (South Norway) and only fjells in the north (Finnmark, Lapland). They are 400 million years old. The coastal mountain region and the larger mountain area in the south of Scandinavia belong to Norway. The inland between Norway and the Baltic sea and the southernmost Scandinavia belongs to Sweden. The peninsula bordering to the gulves of the Baltic sea, the area with a lot of lakes (Järvi-Suomi), north Karelia and Lapland between the Tornio river and the Russian border belong to Finland. Denmark includes the peninsula of Jylland and the islands between Jylland and Sweden.
The bulk of Fennoscandia is separated from the European mainland by the Baltic Sea. It is connected to the mainland from two points: from Karelia, which is east of Finland in Russia, and from Denmark, where Jylland is a peninsula of the European mainland. Geologically most of Denmark is more like Central Europe. (The geology of Central Europe belongs to another node.) The Baltic sea branches to two gulves, Gulf of Finland and Gulf of Bothnia. Gulf of Finland separates the peninsula of Finland from Estonia, and Gulf of Bothnia separates the East and West Bothnias. East Bothnia is in Finland and West Bothnia is in Sweden.
The culture of Fennoscandia is connected, mainly because the Scandinavian peoples live in the whole area. The speakers of Scandinavian languages can understand each other. Finnish is not a Scandinavian language, but Finland has had a great deal of trade and cultural exchange with Scandinavia. In addition, Sweden has conquered and held Finland for centuries.
The Fennoscandian shield is part of the Eurasian tectonic plate. The zone is far from areas of seismic activity, and thus one of the world's stablest bedrocks. Some weak earthquakes occur only in the northest parts, and their highest magnitudes are 3.0 in the Richter scale. The shield of Fennoscandia is an old peneplan area, which is not only very old, but archaean: it's 2700 million years old. That's 60% of the age of the Earth!
Because the shield is very old, the lowlands have been grinded level by erosion. There have been mountain ranges (the Karelides and the Svekofennides) in the area, but only their bases are left.
The bedrock is granite or gneiss, which consist of the same minerals: feldspar, quartz and biotite. They are metamorphous rocks. The soil is acidic, as it is formed from thick, acidic continental lava. (Oceanic lava is fluid and basic.) The acidic soil destroys all paleontologic evidence, which is formed from basic calcium carbonate.
There are kimberlite stoves, like in diamond-rich areas. One Australian company reported finding small diamonds, but before that only microscopic diamonds had been found. In Lapland, there are small amounts of gold - "Lapin Kulta". Only the deposit of Keivitsa seems to be profitable for industrial mining. Some copper has been mined in Karelia, but it is not profitable anymore, so today the company Outokumpu no longer mines in Finland. There are big deposits of iron in Sweden, particularly in Kiruna, where mining continues. Petsamo, which the Soviets conquered, has its famous nickel, which can be found in smaller quantities elsewhere in Fennoscandia.
Most of Fennoscandia is lowland. The mountain range of Scandinavia has glaciers that are small today, but in the last Ice Age they covered the whole of Fennoscandia and even northern Germany. The glacier produced a lot of moraine, which is the most common type of soil in Fennoscandia. Moraine formed when the kilometer-thick moving glacier ground the bedrock under its enormous weight, resulting in a mixture of sand, gravel and stones. The layer of soil on the bedrock is barren and relatively thin (3-4 m), because of the ice. The ultimate erosion, or the all-grinding, rock-crushing glacier is another reason why Fennoscandia is totally hopeless for a paleontologist. The only exceptions are deep caverns, which are extremely rare in the area.
The ice pressed the shield down to the Earth's mantle, so that the northern parts went down and the southern parts up. When the ice melted, Fennoscandia started rising up from the mantle. Even today, land slowly sinks into sea in Denmark and rises in the Gulf of Bothnia. The Baltic sea retreats approximately one metre in a century in the latitude of Vaasa. The peninsula of Finland was only islands just after the ice has melt, but the rising land creates "natular polder". The area of Pohjanmaa is so level because it is former seafloor. This is also the reason why Lake Mälaren has such a curious shape.
The harbours of the cities have to be moved away from the mainland all the time. Ulvila was once in the shore, but today its kilometers from Pori, which in turn is at the shore today. Getting into the harbour of Vaasa requires a detailed map even today. The archipelago of Vaasa is becoming hopelessly difficult to navigate in, because the coastal islands get bigger and new shallows and skerries appear. One acquaintance of mine, who had been driving a boat for decades in Vaasa, was hosting a group of foreigners. They went to a tour in the archipelago, with the acquaintance navigating. She said: "I know all the rocks and shallows here. (BONK!) This is one of them."
The land rises so quickly that I can actually remember when the sea was at a higher level. The rocks in a shore in Vaskiluoto, Vaasa were touched by the sea water all the time back in 1986. The bay in front of the cliffs was about 20-40 cm deep. Today, the land has risen 16 cm, which means that the muddy seafloor in front of the rocks becomes dry land for part of the year, and is then reclaimed by the sea again. The bay will become permanent dry land in my lifetime.
corrections: Ouroboros
me - feldspar is alkaline according to Encyclopedia of Science and Technology