Scandinavian Caledonides

The Scandinavian Caledonides is a belt of deformation in the Earth's crust (known as an orogen) that covers the west and north of the Scandinavian Peninsula. The Scandinavian Caledonides formed as part of the larger Caledonian orogeny that also affected the parts of western and central Europe as well as parts of eastern North America.

The Caledonian orogeny put in place most of the bedrock now seen in the Scandinavian Mountains. Caledonian rocks overlie rocks of the much older Svecokarelian and Sveconorwegian provinces. The Caledonian rocks form large nappes (Swedish: skollor) that have been thrust over the older rocks. Much of the Caledonian rocks have been eroded since they were put in place meaning that they were once thicker and more contiguous. It is also implied from the erosion that the nappes of Caledonian rock originally reached further east than they do today. The erosion has left remaining massifs of Caledonian rocks and windows of Precambrian-aged rock.

While there are some disagreements geologists generally recognize four units among the nappes: an Uppermost, an Upper, a Middle and a Lower one. The last one is made up Ediacaran (Vendian), Cambrian, Ordovician and Silurian-aged sedimentary rocks. Pieces of Precambrian shield rocks are in some places also incorporated into the Lower nappes.

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