New Uppermost Cambrian U-Pb Date from Avalonian Wales and Age of the Cambrian-Ordovician Boundary
| Title | New Uppermost Cambrian U-Pb Date from Avalonian Wales and Age of the Cambrian-Ordovician Boundary |
| Publication Type | Journal Article |
| Year of Publication | 1998 |
| Authors | Davidek, KE, Landing, E, Bowring, SA, Westrop, SR, Rushton, AWA, Fortey, RA, Adrian, JM |
| Journal | Geological Magazine |
| Volume | 135 |
| Pagination | 305-309 |
| Keywords | Cambrian–Ordovician boundary, Late Cambrian, North Wales, U–Pb zircon age |
| Abstract | A crystal-rich volcaniclastic sandstone in the lower Peltura scarabaeoides Zone at Ogof-ddû near Criccieth, North Wales, yields a U–Pb zircon age of 491±1 Ma. This late Late Cambrian date indicates a remarkably young age for the Cambrian–Ordovician boundary whose age must be less than 491 Ma. Hence the revised duration of the post-Placentian (trilobite-bearing) Cambrian indicates that local trilobite zonations allow a biostratigraphic resolution comparable to that provided by Ordovician graptolites and Mesozoic ammonites. |
| URL | http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=4489&fileId=S0016756898008711 |
