Geology of Finland subsequent uplift and erosion would have eroded all of these sediments. In Finland, Caledonian nappes overlie shield rocks of Archean age. Despite occurring in about the same area the Scandinavian Caledonides and the modern Scandinavian Mountains are unrelated. The ice sheet that covered Finland intermittently during the Quaternary grew out from the Scandinavian Mountains. By some estimates the Quaternary glaciers eroded away on average 25 m of rock in Finland, with the degree of erosion being highly variable. Some of the material eroded in Finland has ended up in Germany, Poland, Russia and the Baltic states. Ground till left by
Norway–Russia border of the Norwegian Border Commissioner, while the Russian side is patrolled by the Border Guard Service of Russia. Two-thirds of the border follows two rivers, the Pasvikelva and Jakobselva. The border was defined as a march in a treaty in 1326 and separated which parts of the Sami could be taxed by Norway and Russia. The border line was defined by a treaty in 1826 and essentially remains the same border today. In 1920 Petsamo was ceded to Finland and the border became part of the Finland–Norway border. Petsamo was ceded to the Soviet Union in 1944 and the Norway–Soviet