There are few older orogens in the world,like the Caledonides,where it ispossible to demonstrate many hundreds of kilometers of translation of allochthons,comparable to those in the Himalaya-Tibet mountain belt.In the North Atlantic region(Gee et al 2008),the CaledonideOrogen has its main outcrop areas in the Cenozoic mountains of northeastern Greenland and western Scandinavia,with continuation to the north in Svalbard and the Barents Shelf and southwards into the British Isles.This mid Paleozoic mountain belt,resulting from the collision of the Laurentia and Baltica continents during Scandian Orogeny,involved vast thrust systems that were W-vergent along the Laurentian margin and E-vergent along the Baltoscandian margin of Baltica.Ophiolites are only preservedin Scandinavia.