Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland
Eighty four new U-Th ages are presented for twenty randomly selected broken, displaced and reworked calcite speleothems retrieved from clastic sedimentary fill and from isolated bedding-plane shelves in Crag cave (SW Ireland). The dated pre-Holocene samples span much of the last glacial, ranging in...
Published in: | Quaternary Science Reviews |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Elsevier
2016
|
Subjects: | |
Online Access: | https://centaur.reading.ac.uk/68373/ https://centaur.reading.ac.uk/68373/1/Fankhauser%20et%20al_QSR_2017.pdf |
id |
ftunivreading:oai:centaur.reading.ac.uk:68373 |
---|---|
record_format |
openpolar |
spelling |
ftunivreading:oai:centaur.reading.ac.uk:68373 2024-06-23T07:53:17+00:00 Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland Fankhauser, Adelheid McDermott, Frank Fleitmann, Dominik 2016-11-15 text https://centaur.reading.ac.uk/68373/ https://centaur.reading.ac.uk/68373/1/Fankhauser%20et%20al_QSR_2017.pdf en eng Elsevier https://centaur.reading.ac.uk/68373/1/Fankhauser%20et%20al_QSR_2017.pdf Fankhauser, A., McDermott, F. and Fleitmann, D. <https://centaur.reading.ac.uk/view/creators/90004859.html> (2016) Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland. Quaternary Science Reviews, 152. pp. 104-117. ISSN 0277-3791 doi: https://doi.org/10.1016/j.quascirev.2016.09.019 <https://doi.org/10.1016/j.quascirev.2016.09.019> cc_by_nc_nd_4 Article PeerReviewed 2016 ftunivreading https://doi.org/10.1016/j.quascirev.2016.09.019 2024-06-11T15:05:53Z Eighty four new U-Th ages are presented for twenty randomly selected broken, displaced and reworked calcite speleothems retrieved from clastic sedimentary fill and from isolated bedding-plane shelves in Crag cave (SW Ireland). The dated pre-Holocene samples span much of the last glacial, ranging in age from 85.15 ± 0.60 to 23.45 ± 0.17 ka. Speleothem deposition requires the presence of liquid water, and because Crag cave is a shallow system, deposition is considered likely only when mean annual air temperatures (MAAT) exceed the freezing point of water. Deposition at this mid-latitude ocean-marginal site occurred episodically during MIS5a through to MIS2, synchronously within dating uncertainties, with the timing of Greenland Interstadials (GI). In the latter part of Marine Isotope Stage 3 (MIS3), deposition was particularly intense, consistent with regional scale climate amelioration inferred previously from radiocarbon ages for sparse MIS3 organic and freshwater surficial deposits in N. Ireland. A brief episode of speleothem deposition at c.23.40 ± 0.22 ka coincides with GI-2, demonstrating the sensitivity of the site to brief climate amelioration episodes in Greenland during MIS2. Conditions favourable for speleothem deposition occurred periodically during the last glacial, indicating temperature changes of at least 10oC between stadials and interstadials at this mid-latitude site. Deposition ceased during Greenland Stadials (GS), including during periods of ice-rafting in the adjacent N. Atlantic Ocean (Heinrich events). Oxygen and carbon isotope ratios of the last glacial speleothems are generally elevated, reflecting non-equilibrium isotope fractionation effects. However, establishment of low 13C values often occurred within a few decades of climate amelioration, indicating that biogenic CO2 production resumed rapidly at this site, particularly during MIS3. Speleothem 18O variability was driven largely by long-term changes in the 18O value of the adjacent North Atlantic surface water, in turn largely ... Article in Journal/Newspaper Greenland North Atlantic CentAUR: Central Archive at the University of Reading Greenland Quaternary Science Reviews 152 104 117 |
institution |
Open Polar |
collection |
CentAUR: Central Archive at the University of Reading |
op_collection_id |
ftunivreading |
language |
English |
description |
Eighty four new U-Th ages are presented for twenty randomly selected broken, displaced and reworked calcite speleothems retrieved from clastic sedimentary fill and from isolated bedding-plane shelves in Crag cave (SW Ireland). The dated pre-Holocene samples span much of the last glacial, ranging in age from 85.15 ± 0.60 to 23.45 ± 0.17 ka. Speleothem deposition requires the presence of liquid water, and because Crag cave is a shallow system, deposition is considered likely only when mean annual air temperatures (MAAT) exceed the freezing point of water. Deposition at this mid-latitude ocean-marginal site occurred episodically during MIS5a through to MIS2, synchronously within dating uncertainties, with the timing of Greenland Interstadials (GI). In the latter part of Marine Isotope Stage 3 (MIS3), deposition was particularly intense, consistent with regional scale climate amelioration inferred previously from radiocarbon ages for sparse MIS3 organic and freshwater surficial deposits in N. Ireland. A brief episode of speleothem deposition at c.23.40 ± 0.22 ka coincides with GI-2, demonstrating the sensitivity of the site to brief climate amelioration episodes in Greenland during MIS2. Conditions favourable for speleothem deposition occurred periodically during the last glacial, indicating temperature changes of at least 10oC between stadials and interstadials at this mid-latitude site. Deposition ceased during Greenland Stadials (GS), including during periods of ice-rafting in the adjacent N. Atlantic Ocean (Heinrich events). Oxygen and carbon isotope ratios of the last glacial speleothems are generally elevated, reflecting non-equilibrium isotope fractionation effects. However, establishment of low 13C values often occurred within a few decades of climate amelioration, indicating that biogenic CO2 production resumed rapidly at this site, particularly during MIS3. Speleothem 18O variability was driven largely by long-term changes in the 18O value of the adjacent North Atlantic surface water, in turn largely ... |
format |
Article in Journal/Newspaper |
author |
Fankhauser, Adelheid McDermott, Frank Fleitmann, Dominik |
spellingShingle |
Fankhauser, Adelheid McDermott, Frank Fleitmann, Dominik Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
author_facet |
Fankhauser, Adelheid McDermott, Frank Fleitmann, Dominik |
author_sort |
Fankhauser, Adelheid |
title |
Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
title_short |
Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
title_full |
Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
title_fullStr |
Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
title_full_unstemmed |
Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland |
title_sort |
episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in sw ireland |
publisher |
Elsevier |
publishDate |
2016 |
url |
https://centaur.reading.ac.uk/68373/ https://centaur.reading.ac.uk/68373/1/Fankhauser%20et%20al_QSR_2017.pdf |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland North Atlantic |
genre_facet |
Greenland North Atlantic |
op_relation |
https://centaur.reading.ac.uk/68373/1/Fankhauser%20et%20al_QSR_2017.pdf Fankhauser, A., McDermott, F. and Fleitmann, D. <https://centaur.reading.ac.uk/view/creators/90004859.html> (2016) Episodic speleothem deposition tracks the terrestrial impact of millennial-scale last glacial climate variability in SW Ireland. Quaternary Science Reviews, 152. pp. 104-117. ISSN 0277-3791 doi: https://doi.org/10.1016/j.quascirev.2016.09.019 <https://doi.org/10.1016/j.quascirev.2016.09.019> |
op_rights |
cc_by_nc_nd_4 |
op_doi |
https://doi.org/10.1016/j.quascirev.2016.09.019 |
container_title |
Quaternary Science Reviews |
container_volume |
152 |
container_start_page |
104 |
op_container_end_page |
117 |
_version_ |
1802644853487566848 |