Detailed collections from profiles in the Upper Chasmops Limestone (Oslo-Asker) and Solvang Formation (Ringerike) have yielded a total trilobite fauna of 45 taxa. The stratigraphical distribution of these is presented in the form of faunal logs which show a progressive immigration of forms and increase in diversity. The effect of this is emphasised by a major fauna! shift at the base of overlying shales which are markedly diachronous westwards from Oslo. The trilobite fauna provides the best available means of correlation so far with standard British late Caradoc and early Ashgill shelly assemblages.
Late Caradoc - early Ashgill trilobite distribution in the central Oslo Region, Norway