Biostratigraphy, Biogeography and Shape Analysis of Late Devonian Frasnian Conodonts

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Biostratigraphic analysis of Late Devonian, Frasnian conodont sequences in Euramerica has led to a thirteen-fold zonation in the Montagne Noire, France and a different twelve- fold zonation in the Alberta Rockies. A correlation hypothesis derived from graphic correlation resolves the differences between the two sequences and allows development of a semi-quantitative composite range chart, consisting of 34 composite-standard units. Testing and modification of this standard will be pursued using data from other sequences in Euramerica and the recently acquired collections from Australia, where Montagne Noire zones 3-13 have been identified in preliminary analysis. The Australian sequence will provide a crucial location for an ongoing comprehensive analysis of Frasnian conodont biogeography. Underpinning these studies is a taxonomic base developed from multielement taxonomy and shape analysis. The former was the major taxonomic breakthrough of the 1960s, which has had little impact on Frasnian conodont studies at the species level until the research carried out under PI's previous grants. Shape analysis, especially automated outline analysis, has the potential to quantify evolutionarily significant morphologic characters and transform many of the subjective aspects of taxonomy into a precise methodology.