The age and chronostratigraphical significance of North Atlantic Ash zone II
Abstract Rhyolitic tephra with the geochemical characteristics of North Atlantic Ash Zone (NAAZ) II are described from the giant piston core MD95‐2006 from the northeast Atlantic Ocean. Shard size distribution indicates that the tephra represent a wind‐sorted, primary air‐fall deposit, but with a mo...
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crwiley:10.1002/jqs.821 2024-04-28T08:22:18+00:00 The age and chronostratigraphical significance of North Atlantic Ash zone II Austin, William E. N. Wilson, Lindsay J. Hunt, John B. UK Natural Environment Research Council 2004 http://dx.doi.org/10.1002/jqs.821 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.821 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.821 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Quaternary Science volume 19, issue 2, page 137-146 ISSN 0267-8179 1099-1417 Paleontology Earth and Planetary Sciences (miscellaneous) Arts and Humanities (miscellaneous) journal-article 2004 crwiley https://doi.org/10.1002/jqs.821 2024-04-08T06:54:28Z Abstract Rhyolitic tephra with the geochemical characteristics of North Atlantic Ash Zone (NAAZ) II are described from the giant piston core MD95‐2006 from the northeast Atlantic Ocean. Shard size distribution indicates that the tephra represent a wind‐sorted, primary air‐fall deposit, but with a mode close to 200 μm they are too coarse to be air‐fall deposits at the core site, which lies ca. 1000 km from the possible tephra source. Randomly sampled shards reveal a single geochemical population belonging to the Icelandic transitional alkali magma series, suggesting that they are unlikely to represent ice rafted debris derived from Icelandic icebergs. The tephra probably represent air‐fall deposits, transported to the core site by sea ice within the northeast Atlantic gyre. The NAAZ II peak coincides with the rapid climate transition (cooling) at the end of interstadial 15, which can be assigned an age of 53 260±2660 yr BP from direct correlation with the Greenland ice‐core (GISP2) record. A comparison of the MD95‐2006 Neogloboquadrina pachyderma (sinistral) relative abundance and GISP2 δ 18 O records, relative to the NAAZ II isochron, suggests that this climatic event was synchronous across the North Atlantic. By direct correlation of interstadial maxima between the two records, the GISP2 time‐scale is transferred to MD95‐2006. Comparison of corrected and calibrated radiocarbon ages derived from monospecific foraminifers with the GISP2 ages at the same stratigraphical horizon suggest major age differences. These probably result from large variations in atmospheric 14 C concentration and highlight the significant uncertainties associated with radiocarbon calibration during marine isotope stage 3. Copyright © 2004 John Wiley & Sons, Ltd. Article in Journal/Newspaper Greenland Greenland ice core ice core Neogloboquadrina pachyderma North Atlantic Northeast Atlantic Sea ice Wiley Online Library Journal of Quaternary Science 19 2 137 146 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
topic |
Paleontology Earth and Planetary Sciences (miscellaneous) Arts and Humanities (miscellaneous) |
spellingShingle |
Paleontology Earth and Planetary Sciences (miscellaneous) Arts and Humanities (miscellaneous) Austin, William E. N. Wilson, Lindsay J. Hunt, John B. The age and chronostratigraphical significance of North Atlantic Ash zone II |
topic_facet |
Paleontology Earth and Planetary Sciences (miscellaneous) Arts and Humanities (miscellaneous) |
description |
Abstract Rhyolitic tephra with the geochemical characteristics of North Atlantic Ash Zone (NAAZ) II are described from the giant piston core MD95‐2006 from the northeast Atlantic Ocean. Shard size distribution indicates that the tephra represent a wind‐sorted, primary air‐fall deposit, but with a mode close to 200 μm they are too coarse to be air‐fall deposits at the core site, which lies ca. 1000 km from the possible tephra source. Randomly sampled shards reveal a single geochemical population belonging to the Icelandic transitional alkali magma series, suggesting that they are unlikely to represent ice rafted debris derived from Icelandic icebergs. The tephra probably represent air‐fall deposits, transported to the core site by sea ice within the northeast Atlantic gyre. The NAAZ II peak coincides with the rapid climate transition (cooling) at the end of interstadial 15, which can be assigned an age of 53 260±2660 yr BP from direct correlation with the Greenland ice‐core (GISP2) record. A comparison of the MD95‐2006 Neogloboquadrina pachyderma (sinistral) relative abundance and GISP2 δ 18 O records, relative to the NAAZ II isochron, suggests that this climatic event was synchronous across the North Atlantic. By direct correlation of interstadial maxima between the two records, the GISP2 time‐scale is transferred to MD95‐2006. Comparison of corrected and calibrated radiocarbon ages derived from monospecific foraminifers with the GISP2 ages at the same stratigraphical horizon suggest major age differences. These probably result from large variations in atmospheric 14 C concentration and highlight the significant uncertainties associated with radiocarbon calibration during marine isotope stage 3. Copyright © 2004 John Wiley & Sons, Ltd. |
author2 |
UK Natural Environment Research Council |
format |
Article in Journal/Newspaper |
author |
Austin, William E. N. Wilson, Lindsay J. Hunt, John B. |
author_facet |
Austin, William E. N. Wilson, Lindsay J. Hunt, John B. |
author_sort |
Austin, William E. N. |
title |
The age and chronostratigraphical significance of North Atlantic Ash zone II |
title_short |
The age and chronostratigraphical significance of North Atlantic Ash zone II |
title_full |
The age and chronostratigraphical significance of North Atlantic Ash zone II |
title_fullStr |
The age and chronostratigraphical significance of North Atlantic Ash zone II |
title_full_unstemmed |
The age and chronostratigraphical significance of North Atlantic Ash zone II |
title_sort |
age and chronostratigraphical significance of north atlantic ash zone ii |
publisher |
Wiley |
publishDate |
2004 |
url |
http://dx.doi.org/10.1002/jqs.821 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.821 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.821 |
genre |
Greenland Greenland ice core ice core Neogloboquadrina pachyderma North Atlantic Northeast Atlantic Sea ice |
genre_facet |
Greenland Greenland ice core ice core Neogloboquadrina pachyderma North Atlantic Northeast Atlantic Sea ice |
op_source |
Journal of Quaternary Science volume 19, issue 2, page 137-146 ISSN 0267-8179 1099-1417 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/jqs.821 |
container_title |
Journal of Quaternary Science |
container_volume |
19 |
container_issue |
2 |
container_start_page |
137 |
op_container_end_page |
146 |
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1797584024923799552 |