FRASNIAN (UPPER DEVONIAN) CONODONT SUCCESSION AT HORSE SPRING AND CORRELATIVE SECTIONS, CANNING BASIN, WESTERN AUSTRALIA

The Horse Spring conodont succession in the Canning Basin replicates Zones 6 through 13 of the thirteen-fold Frasnian zonation. Horse Spring, together with other Canning Basin sections, demonstrates the widespread application of the zonation. Furthermore, the recently formalized three-fold subdivision of Zone 13, which has been recognized in the Montagne Noire of southern France, Moroccan Meseta, and northern Ontario, is developed at Horse Spring and other Canning Basin sections. The Canning Basin Frasnian is noteworthy for the high quality of preservation of the conodont faunas, the extremely low CAI values, and the abundance of elements in most collections. The Frasnian in this Western Australian area furnished one of the two case studies used as a basis for the Seddon and Sweet model of depth stratification of conodont biofacies. In contrast, the current study provides evidence for the lateral segregation of conodont communities in the upper surface layer oceanward of the Canning Basin Frasnian reef complex. The emphasis in this research is on the taxonomy of Frasnian Palmatolepis, with seven new species recognized. Complete and partial multielement apparatuses have been reconstructed for two of these.