Potential GSSP of the Global Kungurian Stage: Trapper Creek, Cassia Mountains, southern Idaho and Rockland, Pequop Mountains, northern Nevada.

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Potential GSSP of the Global Kungurian Stage: Trapper Creek, Cassia Mountains, southern Idaho and Rockland, Pequop Mountains, northern Nevada.Vladimir Davydov and Mark D. Schmitz, Boise State UniversityEAR-1004079 ABSTRACTThe completion of the global time scale by the International Commission on Stratigraphy (ICS) is of paramount and pressing importance. Until there are definitions for all stages, the time scale cannot be adequately calibrated with radiometric age dates. Without a reliable and calibrated time scale, efforts to study a host of paleoclimate and paleobiologic and other issues that involve the deep-time geologic record will be limited. The International Commission of Stratigraphy has set 2012 as the deadline for all stages to be defined - and time is running short to get the job done. The requested funds will support a field and lab study of two sections, (Trapper Creek, Cassia Mountains, southern Idaho, and Rockland, Pequop Mountains, northern Nevada), which were proposed recently as the most promising sections to establish a GSSP to define the base of the Kungurian Stage in the Global Chronostratigraphic Scale. Trapper Creek and Rockland are the only easily accessible sections known at the moment where Uralian, N. American and Tethyan conodont faunas co-occur and thus provide global correlation and the only sections where considerable isotopic results are already available. Rockland section is already measured, but PIs will re-measure the transitional beds in both sections at centimeter scale. Additional isotope studies will be performed at geochronology and geochemistry labs in Boise State University. The team of world conodont and fusulinid experts is committed to complete this project as a high priority.