Conference Contribution Details
Mandatory Fields
Fallon, P. & Murray, J.
Palaeontological Association Annual Meeting,
Late Mississippian to Early Pennsylvanian conodonts from western Ireland.
University College Dublin.
Poster Presentation
Optional Fields
During middle Carboniferous (Serpukhovian to Bashkirian) times a widespread unit of non-calcareous dark organic-rich shales was deposited in the Shannon Basin in western Ireland. Mapped regionally as the Clare Shale Formation [CSF], they succeeded an earlier phase of extensive carbonate sedimentation during Tournaisian and Visťan times. While Carboniferous conodont faunas are fairly well documented from the latter (older) carbonate lithologies, they remain poorly understood from younger (largely non-calcareous) strata.† Three stratigraphic sections through the CSF were examined and logged at Paradise House and Inishcorker (both south-central Clare) and also at Ballybunion, Kerry. The unit is largely barren and pyritous; however, discrete bands occur containing a predominantly pelagic fauna of goniatites and thin-shelled bivalves. Previous workers established a detailed biostratigraphic zonation based on these goniatites and suggested a total age of E1c to R1a (Pendleian to Kinderscoutian) for all three sections (combined). Importantly, the CSF at these locations also contains several calcareous nodules which have produced conodonts, including Gnathodus bilineatus and Declinognathodus noduliferus. In addition to allowing the first detailed assessment of conodont biostratigraphic zonation for this part of the Irish Carboniferous, it is expected that the results may also shed light on several conodont evolutionary trends, particularly the Gnathodus-Declinognathodus transition.
Publication Themes