Quantcast

Latest Silurian Stories

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...

2008-06-06 03:00:33

By Oliver, Grahame J H Wilde, Simon A; Wan, Yusheng Abstract: Thirty-seven granitoids from Scotland have been dated using the sensitive high-resolution ion microprobe zircon method. Granitoids were intruded during: (1) crustal stretching at c. 600 Ma after Rodinia broke up (A-types); (2) the Grampian event of crustal thickening when the Midland Valley Arc terrane collided with Laurentia at c. 470 Ma (S-types); (3) erosion and decompression of the over-thickened Laurentian margin at c. 455...

b49399ddf37f19091fbf946b46011b421
2004-12-11 10:54:06

How the earth might recover from a mass extinction is as important as what might have caused the catastrophe in the first place. Penn State astrobiologists are looking at species immigration as one way for the Earth to recover its biodiversity. Astrobiology Magazine -- The length of time necessary to recover from a mass extinction may seem like a problem from the past, but a team of Penn State researchers is investigating recovery from the second largest extinction in Earth's history at the...


Word of the Day
bibliopole
  • A bookseller; now, especially, a dealer in rare and curious books.
This word comes from a Greek phrase meaning 'book seller.'
Related