Magnetizations of Late Ordovician (Caradoc-early Ashgill) age in the paratectonic Caledonides of Wales and the Lake District are directed westerly and northerly respectively. They identify c. 55°) of relative rotation of probable Acadian age. Southward subduction of Iapetus ocean crust occurred in Ordovician times beneath a latitudinally oriented orogen sited in mid-southerly latitudes with the Borrowdale and Snowdonia Volcanic provinces forming parallel fore-arc and back-arc lineaments respectively. Mid-Ordovician to mid-Devonian palaeomagnetic poles from the orogen correlate with contemporaneous Gondwana data to identify a former location sited west of the South American perimeter and not near to North Africa as assumed in previous reconstructions.

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