Comparing Seawater Temperature Proxy Records for the Past 90 Myrs From the Shallow Shelf Record Bass River, New Jersey

Abstract

We present a multiproxy (foraminifer Mg/Ca, δ 18 O, ∆ 47 , and Sr/Ca, and biomarker TEX 86 H , MAT mrs ) low-resolution paleotemperature record based on seven sets of high-resolution time series from the late Cretaceous to Miocene from the Ocean Drilling Program Bass River site, New Jersey Shelf, North Atlantic. Along with insight into long-term climate evolution, this allows testing for internal consistency between proxies. The bottom water temperatures (BWTs) reconstructed using benthic δ 18 O and Mg/Ca values show good agreement in recorded trends with the TEX 86 H sea surface and shallow subsurface temperature record, and with the stacked global benthic oxygen isotope record. The Mg/Ca-based BWTs are higher than the δ 18 O-based BWTs, likely due to uncertainty in the assumptions associated with the Mg/Ca calibration to seawater Mg/Ca. Absolute δ 18 O-based BWT reconstructions are supported by clumped isotope paleothermometry. The agreement in main trends of the independent paleotemperature proxies indicates that the underlying assumed mechanisms for the different proxy relations to temperature stayed largely intact back to at least 90 Ma. Consistent differences in absolute temperature values highlight, however, that a better understanding of the individual proxies is required in order to achieve accurate absolute temperature reconstructions.