The University of Southampton
University of Southampton Institutional Repository

New insights from multi-proxy data from the West Antarctic continental rise: Implications for dating and interpreting Late Quaternary palaeoenvironmental records

New insights from multi-proxy data from the West Antarctic continental rise: Implications for dating and interpreting Late Quaternary palaeoenvironmental records
New insights from multi-proxy data from the West Antarctic continental rise: Implications for dating and interpreting Late Quaternary palaeoenvironmental records
The Antarctic Peninsula’s Pacific margin is one of the best studied sectors of the Antarctic continental margin. Since the 1990s, several research cruises have targeted the continental rise with geophysical surveys, conventional coring and deep-sea drilling. The previous studies highlighted the potential of large sediment drifts on the rise as high-resolution palaeoenvironmental archives. However, these studies also suffered from chronological difficulties arising from the lack of calcareous microfossils, with initial results from geomagnetic relative palaeointensity (RPI) dating promising a possible solution. This paper presents data from new sediment cores recovered on cruise JR298 from seven continental rise sites west of the Antarctic Peninsula and in the Bellingshausen Sea with the objectives to (i) seek calcareous foraminifera, especially at shallow drift sites, to constrain RPI-based age models, and (ii) investigate the depositional history at these locations. We present the results of chronological and multi-proxy analyses on these cores and two cores previously collected from the study area. We establish new age models for the JR298 records and compare them with published RPI-based age models. In addition, we evaluate the reliability of different palaeoproductivity proxies and infer depositional processes. Planktic foraminifera are present in various core intervals. Although their stable oxygen isotope (δ18O) ratios, tephrochronological constraints and glacial-interglacial changes in sediment composition provide age models largely consistent with the RPI chronologies, we also observe distinct differences, predominantly in the Bellingshausen Sea cores. Enrichments of solid-phase manganese together with evidence for “burn-down” of organic carbon in late glacial and peak interglacial sediments document non-steady-state diagenesis that may have altered magnetic mineralogy and, thus, RPI proxies. This process may explain discrepancies between RPI-based age models and those derived from δ18O data combined with tephrochronology. The data also indicate that organic carbon is a much less reliable productivity proxy than biogenic barium or organically-associated bromine in the investigated sediments. In agreement with previous studies, sediment facies indicate a strong control of deposition on the rise by bottom currents that interacted with detritus supplied by meltwater plumes, gravitational down-slope transport processes and pelagic settling of iceberg-rafted debris (IRD) and planktic microfossils. Bottom-current velocities underwent only minor changes over glacial-interglacial cycles at the drift crests, with down-slope deposition only rarely affecting these shallow locations. Maximum concentrations of coarse IRD at the seafloor surfaces of the shallow sites result predominantly from upward pumping caused by extensive bioturbation. This process has to be taken into account when past changes in IRD deposition are inferred from quantifying clasts >1 mm in size.
Antarctic Peninsula, Bioturbation, Bottom current, Carbon burn-down, Contourites, Ice-rafted debris, Manganese enrichment, Non-steady-state diagenesis, Sediment drifts
0277-3791
Hillenbrand, C.-D.
0d081424-9401-4395-9776-efa93f806bba
Crowhurst, S.J.
6d6f1fdb-6c9c-4968-9aa3-9815a4c1b83c
Williams, M.
99ff0c4d-88c1-4bcc-9017-051a8c01837c
Hodell, D.A.
c9977ae9-d52c-4d74-8f01-08391ec61066
McCave, I.N.
87d6ead0-be94-41a2-b39c-8f8d7901868c
Ehrmann, W.
40bba21e-5ad9-4275-acea-bfd058f4c041
Xuan, C.
3f3cad12-b17b-46ae-957a-b362def5b837
Piotrowski, A.M.
9b0f2ed4-4133-4809-a58a-02639f0bba8a
Hernández-Molina, F.J.
256ca467-a4e8-4f24-9ff1-23bd2ab8d28d
Graham, A.G.C.
0043bd2f-103d-4131-8baf-96b6326f394f
Grobe, H.
eeb78aab-82fd-4713-8007-7443ca1f958b
Williams, T.J.
ea3414d2-e467-4449-aa74-3153c80e536d
Horrocks, J.R.
956dcff1-9f7a-427e-af32-2e3ca688442a
Allen, C.S.
473d2ef9-c051-4141-8c81-a593d9f84a1e
Larter, R.D.
70400ac2-66b6-45c1-8a76-0cc978c3d5af
Hillenbrand, C.-D.
0d081424-9401-4395-9776-efa93f806bba
Crowhurst, S.J.
6d6f1fdb-6c9c-4968-9aa3-9815a4c1b83c
Williams, M.
99ff0c4d-88c1-4bcc-9017-051a8c01837c
Hodell, D.A.
c9977ae9-d52c-4d74-8f01-08391ec61066
McCave, I.N.
87d6ead0-be94-41a2-b39c-8f8d7901868c
Ehrmann, W.
40bba21e-5ad9-4275-acea-bfd058f4c041
Xuan, C.
3f3cad12-b17b-46ae-957a-b362def5b837
Piotrowski, A.M.
9b0f2ed4-4133-4809-a58a-02639f0bba8a
Hernández-Molina, F.J.
256ca467-a4e8-4f24-9ff1-23bd2ab8d28d
Graham, A.G.C.
0043bd2f-103d-4131-8baf-96b6326f394f
Grobe, H.
eeb78aab-82fd-4713-8007-7443ca1f958b
Williams, T.J.
ea3414d2-e467-4449-aa74-3153c80e536d
Horrocks, J.R.
956dcff1-9f7a-427e-af32-2e3ca688442a
Allen, C.S.
473d2ef9-c051-4141-8c81-a593d9f84a1e
Larter, R.D.
70400ac2-66b6-45c1-8a76-0cc978c3d5af

Hillenbrand, C.-D., Crowhurst, S.J., Williams, M., Hodell, D.A., McCave, I.N., Ehrmann, W., Xuan, C., Piotrowski, A.M., Hernández-Molina, F.J., Graham, A.G.C., Grobe, H., Williams, T.J., Horrocks, J.R., Allen, C.S. and Larter, R.D. (2021) New insights from multi-proxy data from the West Antarctic continental rise: Implications for dating and interpreting Late Quaternary palaeoenvironmental records. Quaternary Science Reviews, 257, [106842]. (doi:10.1016/j.quascirev.2021.106842).

Record type: Article

Abstract

The Antarctic Peninsula’s Pacific margin is one of the best studied sectors of the Antarctic continental margin. Since the 1990s, several research cruises have targeted the continental rise with geophysical surveys, conventional coring and deep-sea drilling. The previous studies highlighted the potential of large sediment drifts on the rise as high-resolution palaeoenvironmental archives. However, these studies also suffered from chronological difficulties arising from the lack of calcareous microfossils, with initial results from geomagnetic relative palaeointensity (RPI) dating promising a possible solution. This paper presents data from new sediment cores recovered on cruise JR298 from seven continental rise sites west of the Antarctic Peninsula and in the Bellingshausen Sea with the objectives to (i) seek calcareous foraminifera, especially at shallow drift sites, to constrain RPI-based age models, and (ii) investigate the depositional history at these locations. We present the results of chronological and multi-proxy analyses on these cores and two cores previously collected from the study area. We establish new age models for the JR298 records and compare them with published RPI-based age models. In addition, we evaluate the reliability of different palaeoproductivity proxies and infer depositional processes. Planktic foraminifera are present in various core intervals. Although their stable oxygen isotope (δ18O) ratios, tephrochronological constraints and glacial-interglacial changes in sediment composition provide age models largely consistent with the RPI chronologies, we also observe distinct differences, predominantly in the Bellingshausen Sea cores. Enrichments of solid-phase manganese together with evidence for “burn-down” of organic carbon in late glacial and peak interglacial sediments document non-steady-state diagenesis that may have altered magnetic mineralogy and, thus, RPI proxies. This process may explain discrepancies between RPI-based age models and those derived from δ18O data combined with tephrochronology. The data also indicate that organic carbon is a much less reliable productivity proxy than biogenic barium or organically-associated bromine in the investigated sediments. In agreement with previous studies, sediment facies indicate a strong control of deposition on the rise by bottom currents that interacted with detritus supplied by meltwater plumes, gravitational down-slope transport processes and pelagic settling of iceberg-rafted debris (IRD) and planktic microfossils. Bottom-current velocities underwent only minor changes over glacial-interglacial cycles at the drift crests, with down-slope deposition only rarely affecting these shallow locations. Maximum concentrations of coarse IRD at the seafloor surfaces of the shallow sites result predominantly from upward pumping caused by extensive bioturbation. This process has to be taken into account when past changes in IRD deposition are inferred from quantifying clasts >1 mm in size.

Text
1-s2.0-S0277379121000494-main - Version of Record
Available under License Creative Commons Attribution.
Download (10MB)

More information

Accepted/In Press date: 4 February 2021
e-pub ahead of print date: 24 February 2021
Published date: 1 April 2021
Additional Information: Funding Information: We thank the Captain, officers, crew, and shipboard scientists of RRS James Clark Ross cruise JR298, especially J. Channell. Furthermore, we acknowledge S. MacLachlan and her team from the British Ocean Sediment Core Research Facility (BOSCORF Southampton) and V. O'Mahoney and her colleagues from The Queen's Veterinary School Hospital (University of Cambridge) for assistance with physical properties measurements and X-raying, respectively. We are grateful to J. Rolfe (University of Cambridge), S. Haessner (University of Leipzig) and M. Seebeck and R. Fr?hlking (AWI) for support with laboratory analyses. N. Odling (Grant Institute, School of GeoSciences, University of Edinburgh) is acknowledged for conducting the XRF analyses on the discrete sediment samples. We also thank R. Lucchi and T. Williams for their constructive reviews, which improved the paper. This study forms part of the British Antarctic Survey's Polar Science for Planet Earth Programme and was made possible by NERC UK-IODP grants NE/J006513/1 and NE/J006548/1. It has been carried out in collaboration with ?The Drifters? Research Group at Royal Holloway University of London (RHUL) and is related to the TASDRACC Project funded by the Spanish Ministry of Science and Innovation (grants CTM2017-89711-C2-01-P & CTM2017-89711-C2-02-P). Funding Information: We thank the Captain, officers, crew, and shipboard scientists of RRS James Clark Ross cruise JR298, especially J. Channell. Furthermore, we acknowledge S. MacLachlan and her team from the British Ocean Sediment Core Research Facility (BOSCORF Southampton) and V. O’Mahoney and her colleagues from The Queen’s Veterinary School Hospital (University of Cambridge) for assistance with physical properties measurements and X-raying, respectively. We are grateful to J. Rolfe (University of Cambridge), S. Haessner (University of Leipzig) and M. Seebeck and R. Fröhlking (AWI) for support with laboratory analyses. N. Odling (Grant Institute, School of GeoSciences, University of Edinburgh) is acknowledged for conducting the XRF analyses on the discrete sediment samples. We also thank R. Lucchi and T. Williams for their constructive reviews, which improved the paper. This study forms part of the British Antarctic Survey’s Polar Science for Planet Earth Programme and was made possible by NERC UK-IODP grants NE/J006513/1 and NE/J006548/1 . It has been carried out in collaboration with “The Drifters” Research Group at Royal Holloway University of London ( RHUL ) and is related to the TASDRACC Project funded by the Spanish Ministry of Science and Innovation (grants CTM2017-89711-C2-01-P & CTM2017-89711-C2-02-P) . Publisher Copyright: © 2021 The Author(s)
Keywords: Antarctic Peninsula, Bioturbation, Bottom current, Carbon burn-down, Contourites, Ice-rafted debris, Manganese enrichment, Non-steady-state diagenesis, Sediment drifts

Identifiers

Local EPrints ID: 448076
URI: http://eprints.soton.ac.uk/id/eprint/448076
ISSN: 0277-3791
PURE UUID: 5da226a4-8e66-4439-b262-6c5ecbae63ba
ORCID for C. Xuan: ORCID iD orcid.org/0000-0003-4043-3073

Catalogue record

Date deposited: 01 Apr 2021 15:41
Last modified: 15 Nov 2022 02:43

Export record

Altmetrics

Contributors

Author: C.-D. Hillenbrand
Author: S.J. Crowhurst
Author: M. Williams
Author: D.A. Hodell
Author: I.N. McCave
Author: W. Ehrmann
Author: C. Xuan ORCID iD
Author: A.M. Piotrowski
Author: F.J. Hernández-Molina
Author: A.G.C. Graham
Author: H. Grobe
Author: T.J. Williams
Author: J.R. Horrocks
Author: C.S. Allen
Author: R.D. Larter

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×