Ordovician graptolite biostratigraphy in Wales is crude compared with that of the Silurian and is in need of refinement, especially by detailed collecting from suitable sections and consequent taxonomic work. This has been done in parts of the Arenig, Llandeilo and lower Caradoc successions. There is particular potential for subdivision of and improvement in the correlation of the Llanvirn Series and the gracilis-linearis biozones, but there is little prospect of much new and detailed information from the upper Tremadoc or Ashgill Series.

First Page Preview

First page PDF preview
You do not currently have access to this article.