Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea
Laminated diatomaceous sediments occur intermittently in the Bering Sea over the past 5 million years. A varve (annually deposited) origin for the laminae has been suggested, but there is currently no consensus. Here, we report results of a study of two laminated intervals dating from ~528 ka and ~7...
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2023
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ftsouthampton:oai:eprints.soton.ac.uk:486396 2024-02-11T09:58:44+01:00 Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea Onodera, Jonaotaro Kemp, Alan E.S. Pearce, Richard B. Horikawa, Keiji Takahashi, Kozo 2023-12-20 text https://eprints.soton.ac.uk/486396/ https://eprints.soton.ac.uk/486396/1/Onodera_Kemp_accepted.pdf https://eprints.soton.ac.uk/486396/2/1_s2.0_S0377839823001226_main.pdf en English eng https://eprints.soton.ac.uk/486396/1/Onodera_Kemp_accepted.pdf https://eprints.soton.ac.uk/486396/2/1_s2.0_S0377839823001226_main.pdf Onodera, Jonaotaro, Kemp, Alan E.S., Pearce, Richard B., Horikawa, Keiji and Takahashi, Kozo (2023) Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea. Marine Micropaleontology, 186, [102323]. (doi:10.1016/j.marmicro.2023.102323 <http://dx.doi.org/10.1016/j.marmicro.2023.102323>). cc_by_4 Article PeerReviewed 2023 ftsouthampton https://doi.org/10.1016/j.marmicro.2023.102323 2024-01-25T23:21:36Z Laminated diatomaceous sediments occur intermittently in the Bering Sea over the past 5 million years. A varve (annually deposited) origin for the laminae has been suggested, but there is currently no consensus. Here, we report results of a study of two laminated intervals dating from ~528 ka and ~782 ka from IODP Site U1340 on the Bowers Ridge. We combine conventional micropaleontological methods with scanning electron microscope analysis that resolves the seasonal cycle of flux events recorded and demonstrates an annual origin for the laminae. Resting spores of Chaetoceros spp., and more rarely of Thalassiosira antarctica represent early spring blooms with the latter likely due to increased meltwater input. Diatom laminae containing concentrations of Shionodiscus trifultus, Thalassiosira spp., Actinocyclus curvulatus, and Neodenticula seminae, represent flux from the main spring-summer bloom episodes, with the latter indicating influx of seed populations from the North Pacific Alaska Stream. Concentrations of Coscinodiscus spp. in the uppermost part of the diatom laminae represent “Fall Dump” sedimentation of these stratified-adapted diatoms in response to break down of summer stratification in autumn/early-winter storms. The lithogenic laminae represent mainly winter deposition and rare earth element analysis suggests provenance from the southern Bering Sea shelf and the Aleutian Arc. Productivity was high in the studied intervals with total mass fluxes around 5 times higher than modern values. Variation in lamina thickness and diatom composition contain periodicities of 2 - 8 years, as well as a bi-decadal variability likely related to influence of the Pacific Decadal Oscillation. Article in Journal/Newspaper Antarc* Antarctica Bering Sea Alaska University of Southampton: e-Prints Soton Bering Sea Pacific Bowers ENVELOPE(164.083,164.083,-85.000,-85.000) Marine Micropaleontology 186 102323 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
Laminated diatomaceous sediments occur intermittently in the Bering Sea over the past 5 million years. A varve (annually deposited) origin for the laminae has been suggested, but there is currently no consensus. Here, we report results of a study of two laminated intervals dating from ~528 ka and ~782 ka from IODP Site U1340 on the Bowers Ridge. We combine conventional micropaleontological methods with scanning electron microscope analysis that resolves the seasonal cycle of flux events recorded and demonstrates an annual origin for the laminae. Resting spores of Chaetoceros spp., and more rarely of Thalassiosira antarctica represent early spring blooms with the latter likely due to increased meltwater input. Diatom laminae containing concentrations of Shionodiscus trifultus, Thalassiosira spp., Actinocyclus curvulatus, and Neodenticula seminae, represent flux from the main spring-summer bloom episodes, with the latter indicating influx of seed populations from the North Pacific Alaska Stream. Concentrations of Coscinodiscus spp. in the uppermost part of the diatom laminae represent “Fall Dump” sedimentation of these stratified-adapted diatoms in response to break down of summer stratification in autumn/early-winter storms. The lithogenic laminae represent mainly winter deposition and rare earth element analysis suggests provenance from the southern Bering Sea shelf and the Aleutian Arc. Productivity was high in the studied intervals with total mass fluxes around 5 times higher than modern values. Variation in lamina thickness and diatom composition contain periodicities of 2 - 8 years, as well as a bi-decadal variability likely related to influence of the Pacific Decadal Oscillation. |
format |
Article in Journal/Newspaper |
author |
Onodera, Jonaotaro Kemp, Alan E.S. Pearce, Richard B. Horikawa, Keiji Takahashi, Kozo |
spellingShingle |
Onodera, Jonaotaro Kemp, Alan E.S. Pearce, Richard B. Horikawa, Keiji Takahashi, Kozo Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
author_facet |
Onodera, Jonaotaro Kemp, Alan E.S. Pearce, Richard B. Horikawa, Keiji Takahashi, Kozo |
author_sort |
Onodera, Jonaotaro |
title |
Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
title_short |
Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
title_full |
Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
title_fullStr |
Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
title_full_unstemmed |
Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea |
title_sort |
origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle pleistocene age from the southern bering sea |
publishDate |
2023 |
url |
https://eprints.soton.ac.uk/486396/ https://eprints.soton.ac.uk/486396/1/Onodera_Kemp_accepted.pdf https://eprints.soton.ac.uk/486396/2/1_s2.0_S0377839823001226_main.pdf |
long_lat |
ENVELOPE(164.083,164.083,-85.000,-85.000) |
geographic |
Bering Sea Pacific Bowers |
geographic_facet |
Bering Sea Pacific Bowers |
genre |
Antarc* Antarctica Bering Sea Alaska |
genre_facet |
Antarc* Antarctica Bering Sea Alaska |
op_relation |
https://eprints.soton.ac.uk/486396/1/Onodera_Kemp_accepted.pdf https://eprints.soton.ac.uk/486396/2/1_s2.0_S0377839823001226_main.pdf Onodera, Jonaotaro, Kemp, Alan E.S., Pearce, Richard B., Horikawa, Keiji and Takahashi, Kozo (2023) Origins and paleoclimatic and paleoceanographic significance of laminated sediments of middle Pleistocene age from the southern Bering Sea. Marine Micropaleontology, 186, [102323]. (doi:10.1016/j.marmicro.2023.102323 <http://dx.doi.org/10.1016/j.marmicro.2023.102323>). |
op_rights |
cc_by_4 |
op_doi |
https://doi.org/10.1016/j.marmicro.2023.102323 |
container_title |
Marine Micropaleontology |
container_volume |
186 |
container_start_page |
102323 |
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1790594483874693120 |