Defining the Jurassic/Cretaceous Boundary: An Integrated Study from North America with Implications for World-Wide Resolution

9304459 Pessagno PIs将：1)将放射虫和其他微化石与菊石和Buchia生物地层相结合，以便在北美选定的剖面上确定侏罗纪-白垩纪界线（CA，墨西哥）；2)建立磁地层学，并将其与生物地层学联系起来；3)将生物带与地质年代学数据联系起来；4)研究这些剖面的Sr同位素值。样本将从基默里吉纪到瓦兰吉尼亚地层收集，并交给除放射虫和有孔虫以外的菊石和微化石专家。这项工作将有助于确定J/K边界，并有助于更准确地校正北美放射虫带的基于菊石的年代地层。

9304459 Pessagno PIs will: 1) integrate radiolarian and other microfossils with ammonite and Buchia biostratigraphy in order to place the Jurassic- Cretaceous boundary in selected sections in North America (CA, Mexico); 2) establish magnetostratigraphy and relate it to biostratigraphy in these sections; 3) relate biozones to geochronometric data; and 4) examine Sr isotope values in these sections. Samples will be collected from Kimmeridgian to Valanginian strata and farmed out to experts on ammonites and microfossils other than radiolarians and forams. This work will aid in defining the J/K boundary, and contribute to a more accurate ammonite-based chronostratigraphic calibration of North American radiolarian zonation.