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Last updated on April 17, 2014 at 11:32 EDT

Latest Iapetus Ocean Stories

2008-09-19 03:00:23

By Schofield, D I Evans, J A; Millar, I L; Wilby, P R; Aspden, J A A new U-Pb date of 615.2 +- 13 (2sigma) Ma for the Twt Hill Granite, North Wales, contrasts with an Rb-Sr isochron age of 491 +- 12 (2sigma) Ma from the same body. The latter age is thought to result from isotope resetting during regional low-grade metamorphism or fault reactivation. The Rb-Sr age also coincides with the onset of latest Cambrian to Early Tremadoc regression and is taken to reflect tectonic uplift prior to...

2008-08-01 03:00:26

By Steinhoefel, Grit Hegner, Ernst; Oliver, Grahame J H Abstract: Major- and trace-element data and Nd isotope compositions for granitoid samples from the Grampian Highlands in Scotland show a systematic evolution in the composition of their sources in the course of the Caledonian Orogeny. Granitoids of 511- 451 Ma, related to the collision of the Midland Valley island arc with the Grampian terrane, show S-type affinity and fractionated REE patterns with minor Eu anomalies and low initial...