Trans-Atlantic application of the Baltic Middle and Upper Ordovician carbon isotope zonation

Application of the recently introduced Baltic delta C-13 isotope zonation to a composite North American Darriwilian through Hirnantian succession shows that in most intervals there is good trans-Atlantic agreement not only between the isotope zones but also with the available biostratigraphic data. This indicates that this isotope zonation is a useful tool for improving previously uncertain long-distance correlations.