Latest Acadian orogeny Stories
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...
- A spider.
- Figuratively, a peevish, testy, ill-natured person.