A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme
This paper re-evaluates how well quantitative x-ray diffraction (qXRD) can be used as an exploratory method of the weight percentage (wt%) of volcaniclastic sediment, and to identify tephra events in marine cores. In the widely used RockJock v6 software programme, qXRD tephra and glass standards inc...
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Norwegian Polar Institute
2013
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Online Access: | https://doi.org/10.3402/polar.v32i0.11130 https://doaj.org/article/c7ef59bbe3794a76ae309210bf396543 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:c7ef59bbe3794a76ae309210bf396543 2023-05-15T15:13:13+02:00 A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme Dennis D. Eberl Greta B. Kristjánsdóttir John T. Andrews Anne E. Jennings 2013-02-01 https://doi.org/10.3402/polar.v32i0.11130 https://doaj.org/article/c7ef59bbe3794a76ae309210bf396543 en eng Norwegian Polar Institute doi:10.3402/polar.v32i0.11130 0800-0395 1751-8369 https://doaj.org/article/c7ef59bbe3794a76ae309210bf396543 undefined Polar Research, Vol 32, Iss 0, Pp 1-15 (2013) X-ray diffraction tephras Iceland Holocene envir geo Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2013 fttriple https://doi.org/10.3402/polar.v32i0.11130 2023-01-22T19:12:42Z This paper re-evaluates how well quantitative x-ray diffraction (qXRD) can be used as an exploratory method of the weight percentage (wt%) of volcaniclastic sediment, and to identify tephra events in marine cores. In the widely used RockJock v6 software programme, qXRD tephra and glass standards include the rhyodacite White River tephra (Alaska), a rhyolitic tephra (Hekla-4) and the basaltic Saksunarvatn tephra. Experiments of adding known wt% of tephra to felsic bedrock samples indicated that additions ≥10 wt% are accurately detected, but reliable estimates of lesser amounts are masked by amorphous material produced by milling. Volcaniclastic inputs range between 20 and 50 wt%. Primary tephra events are identified as peaks in residual qXRD glass wt% from fourth-order polynomial fits. In cores where tephras have been identified by shard counts in the >150 µm fraction, there is a positive correlation (validation) with peaks in the wt% glass estimated by qXRD. Geochemistry of tephra shards confirms the presence of several Hekla-sourced tephras in cores B997-317PC1 and -319PC2 on the northern Iceland shelf. In core B997-338 (north-west Iceland), there are two rhyolitic tephras separated by ca. 100 cm with uncorrected radiocarbon dates on articulated shells of around 13 000 yr B.P. These tephras may be correlatives of the Borrobol and Penifiler tephras found in Scotland. The number of Holocene tephra events per 1000 yr was estimated from qXRD on 16 cores and showed a bimodal distribution with an increased number of events in both the late and early Holocene. Article in Journal/Newspaper Arctic Hekla Iceland Polar Research Alaska Unknown Arctic Saksunarvatn ENVELOPE(-7.150,-7.150,62.233,62.233) Polar Research 32 1 11130 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
X-ray diffraction tephras Iceland Holocene envir geo |
spellingShingle |
X-ray diffraction tephras Iceland Holocene envir geo Dennis D. Eberl Greta B. Kristjánsdóttir John T. Andrews Anne E. Jennings A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
topic_facet |
X-ray diffraction tephras Iceland Holocene envir geo |
description |
This paper re-evaluates how well quantitative x-ray diffraction (qXRD) can be used as an exploratory method of the weight percentage (wt%) of volcaniclastic sediment, and to identify tephra events in marine cores. In the widely used RockJock v6 software programme, qXRD tephra and glass standards include the rhyodacite White River tephra (Alaska), a rhyolitic tephra (Hekla-4) and the basaltic Saksunarvatn tephra. Experiments of adding known wt% of tephra to felsic bedrock samples indicated that additions ≥10 wt% are accurately detected, but reliable estimates of lesser amounts are masked by amorphous material produced by milling. Volcaniclastic inputs range between 20 and 50 wt%. Primary tephra events are identified as peaks in residual qXRD glass wt% from fourth-order polynomial fits. In cores where tephras have been identified by shard counts in the >150 µm fraction, there is a positive correlation (validation) with peaks in the wt% glass estimated by qXRD. Geochemistry of tephra shards confirms the presence of several Hekla-sourced tephras in cores B997-317PC1 and -319PC2 on the northern Iceland shelf. In core B997-338 (north-west Iceland), there are two rhyolitic tephras separated by ca. 100 cm with uncorrected radiocarbon dates on articulated shells of around 13 000 yr B.P. These tephras may be correlatives of the Borrobol and Penifiler tephras found in Scotland. The number of Holocene tephra events per 1000 yr was estimated from qXRD on 16 cores and showed a bimodal distribution with an increased number of events in both the late and early Holocene. |
format |
Article in Journal/Newspaper |
author |
Dennis D. Eberl Greta B. Kristjánsdóttir John T. Andrews Anne E. Jennings |
author_facet |
Dennis D. Eberl Greta B. Kristjánsdóttir John T. Andrews Anne E. Jennings |
author_sort |
Dennis D. Eberl |
title |
A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
title_short |
A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
title_full |
A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
title_fullStr |
A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
title_full_unstemmed |
A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme |
title_sort |
quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off iceland: a contribution to the volcanoes in the arctic system programme |
publisher |
Norwegian Polar Institute |
publishDate |
2013 |
url |
https://doi.org/10.3402/polar.v32i0.11130 https://doaj.org/article/c7ef59bbe3794a76ae309210bf396543 |
long_lat |
ENVELOPE(-7.150,-7.150,62.233,62.233) |
geographic |
Arctic Saksunarvatn |
geographic_facet |
Arctic Saksunarvatn |
genre |
Arctic Hekla Iceland Polar Research Alaska |
genre_facet |
Arctic Hekla Iceland Polar Research Alaska |
op_source |
Polar Research, Vol 32, Iss 0, Pp 1-15 (2013) |
op_relation |
doi:10.3402/polar.v32i0.11130 0800-0395 1751-8369 https://doaj.org/article/c7ef59bbe3794a76ae309210bf396543 |
op_rights |
undefined |
op_doi |
https://doi.org/10.3402/polar.v32i0.11130 |
container_title |
Polar Research |
container_volume |
32 |
container_issue |
1 |
container_start_page |
11130 |
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1766343806421041152 |