Review of the Ordovician biostratigraphy of the Herscheid Schichten (Rheinisches Schiefergebirge, Germany)

The biostratigraphy of the Ordovician of the Ebbe and Remscheid-Altena anti clines is reviewed. Graptolite, trilobite and chitinozoan records enable to date the Herscheid Schichten with their succession of Plettenberger Bander schiefer, Unterer Tonschiefer, Grauwackenschiefer and Oberer Tonschiefer as Middle to Upper Ordovician. Based on the record of Holmograptus lentils Zo ne graptolites, the Plettenberger Banderschiefer is referred to the early A bereiddian (Llanvirn). The Unterer Tonschiefer bears graptolites of the Nic holsonograptus fasciculatus Zone (Abereiddian, Llanvirn). The youngest date d strata include the "Kieselgallen" of the Grauwackenschiefer with chitinoz oans of the Lagenochitina ponceti to Lagenochitina deunffi Zones of basal C aradoc age. The Oberer Tonschiefer is of Late Ordovician age, based on the poor trilobite fauna.