Beryllium isotopes in central Arctic Ocean sediments over the past 12.3 million years: Stratigraphic and paleoclimatic implications

Authors

Martin Frank
Jan Backman, University of Rhode Island
Martin Jakobsson, University of Rhode Island
Kate Moran, University of Rhode Island
Matthew O'Regan, University of Rhode Island
John W. King, University of Rhode IslandFollow
Brian A. Haley
Peter W. Kubik
Dieter Garbe-Schönberg

Document Type

Article

Date of Original Version

2008

Department

Oceanography

Abstract

The upper 200 m of the sediments recovered during IODP Leg 302, the Arctic Coring Expedition (ACEX), to the Lomonosov Ridge in the central Arctic Ocean consist almost exclusively of detrital material. The scarcity of biostratigraphic markers severely complicates the establishment of a reliable chronostratigraphic framework for these sediments, which contain the first continuous record of the Neogene environmental and climatic evolution of the Arctic region. Here we present profiles of cosmogenic ¹⁰Be together with the seawater‐derived fraction of stable ⁹Be obtained from the ACEX cores. The down‐core decrease of ¹⁰Be/⁹Be provides an average sedimentation rate of 14.5 ± 1 m/Ma for the uppermost 151 m of the ACEX record and allows the establishment of a chronostratigraphy for the past 12.3 Ma. The age‐corrected ¹⁰Be concentrations and ¹⁰Be/⁹Be ratios suggest the existence of an essentially continuous sea ice cover over the past 12.3 Ma.

Citation/Publisher Attribution

Frank, M., J. Backman, M. Jakobsson, K. Moran, M. O’Regan, J. King, B. A. Haley, P. W. Kubik, and D. Garbe-Scho¨nberg (2008), Beryllium isotopes in central Arctic Ocean sediments over the past 12.3 million years: Stratigraphic and paleoclimatic implications, Paleoceanography, 23, PA1S02, doi:10.1029/2007PA001478

Available at: https://doi.org/10.1029/2007PA001478