Temperature and salinity of the Late Cretaceous Western Interior Seaway (original) (raw)

Data Repository Figure 2 (DR2).  18 O w vs. Paleo-Latitude  18 Ow vs. Paleo-Latitude for samples measured in this study. For comparison, two typical assumptions of  18 Ow are shown. These are 1)  18 Ow =-1.0‰ (VSMOW) everywhere (solid line), representing an ice-free world (Shackleton and Kennett, 1975); or 2) the ice-free value adjusted to account for the modern meridional gradient in  18 Ow (dashed line) (Zachos et al, 1994), giving-0.4 to-1.1‰ (VSMOW) for the latitude range covering the WIS. The data show much more variability than predicted by either of these traditional assumptions, potentially explaining why early attempts at reconstructing WIS paleotemperatures failed to produce reasonable temperatures when they assumed a constant  18