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The geology of Norway encompasses the history of earth that can be interpreted by rock types found in Norway, and the associated sedimentological history of soils and rock types. The Norwegian mountains were formed around 400 million years ago (Ma) during the Caledonian orogeny. ==Precambrian== Rocks of Archean age in Norway are confined to a few 10 km-scale areas within younger metamorphic belts exposed on islands off the west coast of northern Norway and as smaller fragments locally in the Western Gneiss Region in south-central Norway. Despite intense reworking during the Caledonian orogeny in some areas, three major belts can be recognised in the Proterozoic rocks of Norway, the Neoproterozoic and Mesoproterozoic Gothian and Sveconorwegian, the Palaeoproterozoic Svecokarelian and the intervening Transscandinavian Igneous Belt of late Palaeoproterozoic age. The later part of the Neoproterozoic records the break-up of the Rodinia supercontinent and the formation of the Iapetus Ocean. Passive margin sequences are preserved within the lowermost allochthon and parautochthon of the Caledonian thrust sheets. In southern Norway the sequence is known as ''Sparagmite''. The depositional environment changes from fluvial in the parautochthon to deepwater marine in the lowermost allochthon consistent with a paleogeography of an originally westward deepening basin. The uppermost part of the Neoproterozoic sequence throughout Norway includes a tillite, a record of the Varanger ice age which occurred between roughly 630-590 Ma, the final part of the Cryogenian Period. This was followed by fluvial and shallow water marine deposits of the Ediacaran before a major marine transgression at the start of the Cambrian. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geology of Norway」の詳細全文を読む スポンサード リンク
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