Conodont Biostratigraphy of the Upper Cambrian -- Lowest Ordovician and International Correlation of the Cambrian-Ordovician Boundary

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Cambro-Ordovician conodonts are abundant and the same species are more widely distributed than other contemporaneous fossil groups. Because of their utility they will be the primary group utilized for choice of a boundary point by the International Working Group on the Cambrian-Ordovician Boundary. The project will fund the PI's continuing work as Secretary of this committee. Other aspects of the project are study of Cambro-Ordovician eustatic sea-level fluctuations. Strata in Nevada deposited during these sea-level changes will be studied in cooperation with U.S. Geological Survey personnel who have studied the Nevada strata and equivalent beds in Kazakhstan. The goal of this part of the research is to correlate unusual sedimentation patterns in platform and continental-slope deposits in these areas. A final aspect of the study is continuation of a project on biostratigraphy and paleoecology of Cambro-Ordovician conodonts in western Utah. Facies changes in the area make it a natural laboratory for study of the Cambro-Ordovician conodont paleoecology and the influence of facies changes on conodont biostratigraphy. Some of these facies changes are related to the eustatic fluctuations discussed above and can be correlated with data on sedimentation patterns in Nevada, Kazakhstan, and other areas to form an integrated picture of the effects of these eustatic events. These events are related to faunal extinctions and evolutionary changes which must be understood before a Cambrian-Ordovician boundary point can be chosen wisely.