- journal_title：Journal of the Geological Society
- Contributor：A.Mattias Lundmark ; Roy H. Gabrielsen ; John Flett Brown
- Publisher：Geological Society of London
- Date：2011-
- Format：text/html
- Language：en
- Identifier：10.1144/0016-76492011-017
- journal_abbrev：Journal of the Geological Society
- issn：0016-7649
- volume：168
- issue：6
- firstpage：1233
- section：Special
Magmatic zircon in the syenite (bostonite) part of a composite NE–SW-trending cogenetic bostonite–camptonite dyke in Orkney, Scotland, yields a laser ablation inductively coupled plasma mass spectrometry age of 313 ± 4 Ma and εHf(313 Ma) values of +6 to +11. This suggests that the NE–SW-, east–west- and NW–SE-trending Scottish lamprophyre dyke swarms were emplaced during one late Carboniferous magmatic event, contrasting with published K–Ar dates ranging between c. 325 and 250 Ma. This magmatism is interpreted as a response to late Variscan regional extension or an early response to the Skagerrak mantle plume. Lamprophyre magmatism was initiated some 10 Ma earlier in Scotland than in the Oslo Rift.