Bedrock of SwedenSweden's bedrock consists of three main units, the rock, the remains of a sediment rock cover and the mountain bedrock.The Swedish rock is part of a stable area, the so-called Fennoskandian urberg sköld (see map below). This is made up of rocks formed during precambrian times, that is, from the time of earth formation about 4 600 million years ago and until cambrium about 545 million years ago. The Phennoscandian urberg shield (of fenno- "Finnish" and Scandia "Scandinavia") is in turn part of the paleocontinent Baltika. It consists of the older rocks in smaller parts of Norway, large parts of Sweden, all of Finland and northwestern Russia.The oldest rocks in Sweden are Archaean, i.e. more than 2,500 million years old, and have given ages between 2,800 and 2,600 million years for age determinations. Rocks of archaic age occur to a limited extent in northernmost Sweden.The rocks in the rest of northern and eastern and southeastern Sweden are mainly about 2,000–1,650 million years old. They are formed and in many cases also transformed in connection with the so-called deceitful ocaresque mountain chain formation. The latter has also affected the Archaean rocks.The bedrock in southwestern Sweden is between 1,700 and 1,550 million years old and has since been heavily transformed during the so-called betrayal onvegic mountain chain formation that took place about 1,100-900 million years ago. In southern Western Sweden and Blekinge there are also remnants of extensive transformations of the bedrock about 1,450–1,400 million years ago.On top of the rock shield are fanerozoic sedimentary rocks that are younger than about 545 million years. These today cover the rock mountain in large parts of Skåne, Öland and Gotland, Östgöta- och Närkeslätten, Västgötabergen, as well as the area around Siljan in Dalarna and along the mountain edge. The youngest rocks in Sweden are tertiary, about 55 million years old formations, which occur in the southernmost and southwesternmost Skåne.The youngest rock chain formation in Sweden's bedrock is the Caledonian, which occurred about 510–400 million years ago. At that time, the rocks in the Scandinavian mountain range got their current design. The rocks in the mountain range are of precambrian to Siberian ages, that is, they are older than about 420 million years old.The Scandinavian mountain range to Spitsbergen is part of the Caledonian sands or the Caledonian mountain range. This mountain range also covers parts of north-west Ireland, the mountainous areas of northern Scotland and North Greenland. Its North American part is appalachia.
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