Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand
We present palaeomagnetic and cosmogenic radionuclide records of the Laschamp geomagnetic excursion in Lake Pupuke, a maar lake in Auckland, New Zealand. Laschamp was identified by a combination of relative palaeointensity, 10Be and 14C data from the lake sediments and represents the first such reco...
Published in: | Earth and Planetary Science Letters |
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ftunivauckland:oai:researchspace.auckland.ac.nz:2292/11932 2023-05-15T16:29:38+02:00 Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand Nilsson, A Muscheler, R Snowball, I Aldahan, A Possnert, G Augustinus, P Atkin, D Stephens, T 2011 http://hdl.handle.net/2292/11932 https://doi.org/10.1016/j.epsl.2011.08.050 unknown Elsevier B.V. Earth and Planetary Science Letters Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. Details obtained from http://www.sherpa.ac.uk/romeo/issn/0012-821X/ https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm Copyright: Elsevier B.V. http://purl.org/eprint/accessRights/RestrictedAccess http://dx.doi.org/10.1016/j.epsl.2011.08.050 Journal Article 2011 ftunivauckland https://doi.org/10.1016/j.epsl.2011.08.050 2013-12-07T09:25:36Z We present palaeomagnetic and cosmogenic radionuclide records of the Laschamp geomagnetic excursion in Lake Pupuke, a maar lake in Auckland, New Zealand. Laschamp was identified by a combination of relative palaeointensity, 10Be and 14C data from the lake sediments and represents the first such record from the Southern Hemisphere. Despite the high organic carbon content, which causes relatively weak natural remanent magnetisations, the geomagnetic intensity minimum associated with the Laschamp excursion is identifiable as a relative palaeointensity minimum that is synchronous with (i) a peak in 10Be concentration and (ii) an anomaly in Δ14C. The Lake Pupuke time scale, provided by 14C data calibrated with INTCAL09, places the 10Be maximum at the same time as a 10Be maximum in Greenland ice cores when secured to the GICC05 time scale. The central age of the Laschamp geomagnetic excursion in Lake Pupuke as defined by the 10Be prediction peak is c. 41 kyr, which confirms its global application as a palaeomagnetic isochron. Anomalous palaeomagnetic directional data at c. 32 kyr in the Lake Pupuke sediments may represent the Mono Lake geomagnetic excursion, but tephra layers caused by frequent eruptions in the Auckland volcanic field during this excursion probably disrupted the palaeointensity signal. The study highlights the value of combining traditional palaeomagnetic methods with measurements of cosmogenic radionuclides in the quest for accurate and precise geochronologies during MIS3, a time of rapid global climate change. Article in Journal/Newspaper Greenland Greenland ice cores University of Auckland Research Repository - ResearchSpace Greenland New Zealand Earth and Planetary Science Letters 311 1-2 155 164 |
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Open Polar |
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University of Auckland Research Repository - ResearchSpace |
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ftunivauckland |
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unknown |
description |
We present palaeomagnetic and cosmogenic radionuclide records of the Laschamp geomagnetic excursion in Lake Pupuke, a maar lake in Auckland, New Zealand. Laschamp was identified by a combination of relative palaeointensity, 10Be and 14C data from the lake sediments and represents the first such record from the Southern Hemisphere. Despite the high organic carbon content, which causes relatively weak natural remanent magnetisations, the geomagnetic intensity minimum associated with the Laschamp excursion is identifiable as a relative palaeointensity minimum that is synchronous with (i) a peak in 10Be concentration and (ii) an anomaly in Δ14C. The Lake Pupuke time scale, provided by 14C data calibrated with INTCAL09, places the 10Be maximum at the same time as a 10Be maximum in Greenland ice cores when secured to the GICC05 time scale. The central age of the Laschamp geomagnetic excursion in Lake Pupuke as defined by the 10Be prediction peak is c. 41 kyr, which confirms its global application as a palaeomagnetic isochron. Anomalous palaeomagnetic directional data at c. 32 kyr in the Lake Pupuke sediments may represent the Mono Lake geomagnetic excursion, but tephra layers caused by frequent eruptions in the Auckland volcanic field during this excursion probably disrupted the palaeointensity signal. The study highlights the value of combining traditional palaeomagnetic methods with measurements of cosmogenic radionuclides in the quest for accurate and precise geochronologies during MIS3, a time of rapid global climate change. |
format |
Article in Journal/Newspaper |
author |
Nilsson, A Muscheler, R Snowball, I Aldahan, A Possnert, G Augustinus, P Atkin, D Stephens, T |
spellingShingle |
Nilsson, A Muscheler, R Snowball, I Aldahan, A Possnert, G Augustinus, P Atkin, D Stephens, T Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
author_facet |
Nilsson, A Muscheler, R Snowball, I Aldahan, A Possnert, G Augustinus, P Atkin, D Stephens, T |
author_sort |
Nilsson, A |
title |
Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
title_short |
Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
title_full |
Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
title_fullStr |
Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
title_full_unstemmed |
Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand |
title_sort |
multi-proxy identification of the laschamp geomagnetic field excursion in lake pupuke, new zealand |
publisher |
Elsevier B.V. |
publishDate |
2011 |
url |
http://hdl.handle.net/2292/11932 https://doi.org/10.1016/j.epsl.2011.08.050 |
geographic |
Greenland New Zealand |
geographic_facet |
Greenland New Zealand |
genre |
Greenland Greenland ice cores |
genre_facet |
Greenland Greenland ice cores |
op_source |
http://dx.doi.org/10.1016/j.epsl.2011.08.050 |
op_relation |
Earth and Planetary Science Letters |
op_rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. Details obtained from http://www.sherpa.ac.uk/romeo/issn/0012-821X/ https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm Copyright: Elsevier B.V. http://purl.org/eprint/accessRights/RestrictedAccess |
op_doi |
https://doi.org/10.1016/j.epsl.2011.08.050 |
container_title |
Earth and Planetary Science Letters |
container_volume |
311 |
container_issue |
1-2 |
container_start_page |
155 |
op_container_end_page |
164 |
_version_ |
1766019344947478528 |