Caledonian orogeny Caledonian orogeny The Caledonian orogeny was a mountain-building era recorded in the northern parts of Ireland and Britain, the Scandinavian Mountains, Svalbard, eastern Greenland and parts of north-central Europe. The Caledonian orogeny encompasses events that occurred from the Ordovician to Early Devonian, roughly 490–390 million years ago (Ma). It was caused by the closure of the Iapetus Ocean when the continents and terranes of Laurentia, Baltica and Avalonia collided. The Caledonian orogeny is named for Caledonia, the Latin name for Scotland. The name was first used in 1885 by Austrian geologist Eduard Suess for an episode of mountain building in
Petermann Orogeny a set of vertically arcuate thrust faults which dip toward each other and accommodate vertical movement by essentially "squeezing" the central block up and out. Several northeast trending discontinuities including the Mundrabilla lineament divide the Petermann orogeny, with extensive vertical offsets across them, usually west-side-up, though the timing of this event is unknown. Six deformations are known (to be completed) Foliations associated with the Petermann Orogeny are typically steeply to gently south-dipping and subparallel to the thrust faults upon which they were developed. S regionally pervasive stretching lineation is potentially associated with some of these faults, especially in the deeper