Abstract

Reconstructing hydrological conditions of past warm periods, such as the Eocene ‘hot house’ provides empirical data to compare to state of the art climate models. However, reconstructing these changes in deep time is challenging, for example, given the complex interplay between evapotranspiration, precipitation and runoff. As a proxy for past changes in these hydrological systems, the dynamics of fresh water input into marginal seas can be used to identify the spatiotemporal distribution of riverine runoff. Elemental barium (Ba) and radiogenic strontium (87Sr) are, depending on the amount of runoff and the background geology of the catchment area, typically enriched in river waters in comparison to seawater and can thus be utilized to determine changes in riverine fresh water discharge. Here, we use barium to calcium ratios (Ba/Ca) and radiogenic strontium isotopes (87Sr/86Sr) measured in fossil bivalve shells to reconstruct patterns of fresh water input into the paleo North Sea during the early to middle Eocene. Our reconstruction shows the potential of Ba/Ca and 87Sr/86Sr to serve as proxies for riverine runoff and highlights the spatiotemporal complexity of Eocene hydrological conditions in western Europe. In particular, our results enable changes in riverine input along geological to perennial time scales for different coastal regions to be determined, revealing a steady influx of fresh water, but with distinct spatiotemporal differences.

Details

Title
Spatiotemporal changes in riverine input into the Eocene North Sea revealed by strontium isotope and barium analysis of bivalve shells
Author
Kniest, Jorit F. 1 ; Evans, David 2 ; Gerdes, Axel 3 ; Cantine, Marjorie 4 ; Todd, Jonathan A. 5 ; Sigwart, Julia D. 6 ; Vellekoop, Johan 7 ; Müller, Wolfgang 3 ; Voigt, Silke 3 ; Raddatz, Jacek 1 

 Goethe University Frankfurt, Institute of Geosciences, Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); Goethe University Frankfurt, Frankfurt Isotope and Element Research Center (FIERCE), Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany (GRID:grid.15649.3f) (ISNI:0000 0000 9056 9663) 
 Goethe University Frankfurt, Institute of Geosciences, Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); Goethe University Frankfurt, Frankfurt Isotope and Element Research Center (FIERCE), Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); University of Southampton, School of Ocean & Earth Science, Southampton, UK (GRID:grid.5491.9) (ISNI:0000 0004 1936 9297) 
 Goethe University Frankfurt, Institute of Geosciences, Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); Goethe University Frankfurt, Frankfurt Isotope and Element Research Center (FIERCE), Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721) 
 Goethe University Frankfurt, Institute of Geosciences, Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); Goethe University Frankfurt, Frankfurt Isotope and Element Research Center (FIERCE), Frankfurt, Germany (GRID:grid.7839.5) (ISNI:0000 0004 1936 9721); University of Washington, Department of Earth and Space Sciences, Seattle, USA (GRID:grid.34477.33) (ISNI:0000000122986657) 
 The Natural History Museum, London, UK (GRID:grid.35937.3b) (ISNI:0000 0001 2270 9879) 
 Senckenberg Institute and Natural History Museum, Department of Marine Zoology, Frankfurt, Germany (GRID:grid.35937.3b) 
 KU Leuven, Department of Earth and Environmental Sciences, Leuven, Belgium (GRID:grid.5596.f) (ISNI:0000 0001 0668 7884); Institute of Natural Sciences, Operational Directorate Earth and History of Life, Brussels, Belgium (GRID:grid.20478.39) (ISNI:0000 0001 2171 9581) 
Pages
28806
Publication year
2024
Publication date
2024
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3131034346
Copyright
© The Author(s) 2024. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.