Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard)
The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circ...
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ftdoajarticles:oai:doaj.org/article:e6cb2028387648ab812438a28a4f3e70 2023-05-15T14:56:44+02:00 Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) R. S. Hindshaw N. J. Tosca A. M. Piotrowski E. T. Tipper 2018-03-01T00:00:00Z https://doi.org/10.5194/esurf-6-141-2018 https://doaj.org/article/e6cb2028387648ab812438a28a4f3e70 EN eng Copernicus Publications https://www.earth-surf-dynam.net/6/141/2018/esurf-6-141-2018.pdf https://doaj.org/toc/2196-6311 https://doaj.org/toc/2196-632X doi:10.5194/esurf-6-141-2018 2196-6311 2196-632X https://doaj.org/article/e6cb2028387648ab812438a28a4f3e70 Earth Surface Dynamics, Vol 6, Pp 141-161 (2018) Dynamic and structural geology QE500-639.5 article 2018 ftdoajarticles https://doi.org/10.5194/esurf-6-141-2018 2022-12-31T01:36:09Z The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circum-Arctic source regions are poorly characterised in terms of their Sr and Nd isotopic compositions. In this study we present Sr and Nd isotope data from the Paleogene Central Basin sediments of Svalbard, including the first published data of stream suspended sediments from Svalbard. The stream suspended sediments exhibit considerable isotopic variation ( ε Nd = −20.6 to −13.4; 87 Sr ∕ 86 Sr = 0.73421 to 0.74704) which can be related to the depositional history of the sedimentary formations from which they are derived. In combination with analysis of the clay mineralogy of catchment rocks and sediments, we suggest that the Central Basin sedimentary rocks were derived from two sources. One source is Proterozoic sediments derived from Greenlandic basement rocks which are rich in illite and have high 87 Sr ∕ 86 Sr and low ε Nd values. The second source is Carboniferous to Jurassic sediments derived from Siberian basalts which are rich in smectite and have low 87 Sr ∕ 86 Sr and high ε Nd values. Due to a change in depositional conditions throughout the Paleogene (from deep sea to continental) the relative proportions of these two sources vary in the Central Basin formations. The modern stream suspended sediment isotopic composition is then controlled by modern processes, in particular glaciation, which determines the present-day exposure of the formations and therefore the relative contribution of each formation to the stream suspended sediment load. This study demonstrates that the Nd isotopic composition of stream suspended sediments exhibits seasonal variation, which likely mirrors longer-term hydrological changes, with implications for source provenance studies based on fixed end-members through time. Article in Journal/Newspaper Arctic Arctic Ocean greenlandic Svalbard Directory of Open Access Journals: DOAJ Articles Arctic Arctic Ocean Central Basin ENVELOPE(43.000,43.000,73.500,73.500) Svalbard Earth Surface Dynamics 6 1 141 161 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Dynamic and structural geology QE500-639.5 |
spellingShingle |
Dynamic and structural geology QE500-639.5 R. S. Hindshaw N. J. Tosca A. M. Piotrowski E. T. Tipper Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
topic_facet |
Dynamic and structural geology QE500-639.5 |
description |
The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circum-Arctic source regions are poorly characterised in terms of their Sr and Nd isotopic compositions. In this study we present Sr and Nd isotope data from the Paleogene Central Basin sediments of Svalbard, including the first published data of stream suspended sediments from Svalbard. The stream suspended sediments exhibit considerable isotopic variation ( ε Nd = −20.6 to −13.4; 87 Sr ∕ 86 Sr = 0.73421 to 0.74704) which can be related to the depositional history of the sedimentary formations from which they are derived. In combination with analysis of the clay mineralogy of catchment rocks and sediments, we suggest that the Central Basin sedimentary rocks were derived from two sources. One source is Proterozoic sediments derived from Greenlandic basement rocks which are rich in illite and have high 87 Sr ∕ 86 Sr and low ε Nd values. The second source is Carboniferous to Jurassic sediments derived from Siberian basalts which are rich in smectite and have low 87 Sr ∕ 86 Sr and high ε Nd values. Due to a change in depositional conditions throughout the Paleogene (from deep sea to continental) the relative proportions of these two sources vary in the Central Basin formations. The modern stream suspended sediment isotopic composition is then controlled by modern processes, in particular glaciation, which determines the present-day exposure of the formations and therefore the relative contribution of each formation to the stream suspended sediment load. This study demonstrates that the Nd isotopic composition of stream suspended sediments exhibits seasonal variation, which likely mirrors longer-term hydrological changes, with implications for source provenance studies based on fixed end-members through time. |
format |
Article in Journal/Newspaper |
author |
R. S. Hindshaw N. J. Tosca A. M. Piotrowski E. T. Tipper |
author_facet |
R. S. Hindshaw N. J. Tosca A. M. Piotrowski E. T. Tipper |
author_sort |
R. S. Hindshaw |
title |
Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
title_short |
Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
title_full |
Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
title_fullStr |
Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
title_full_unstemmed |
Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard) |
title_sort |
clay mineralogy, strontium and neodymium isotope ratios in the sediments of two high arctic catchments (svalbard) |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/esurf-6-141-2018 https://doaj.org/article/e6cb2028387648ab812438a28a4f3e70 |
long_lat |
ENVELOPE(43.000,43.000,73.500,73.500) |
geographic |
Arctic Arctic Ocean Central Basin Svalbard |
geographic_facet |
Arctic Arctic Ocean Central Basin Svalbard |
genre |
Arctic Arctic Ocean greenlandic Svalbard |
genre_facet |
Arctic Arctic Ocean greenlandic Svalbard |
op_source |
Earth Surface Dynamics, Vol 6, Pp 141-161 (2018) |
op_relation |
https://www.earth-surf-dynam.net/6/141/2018/esurf-6-141-2018.pdf https://doaj.org/toc/2196-6311 https://doaj.org/toc/2196-632X doi:10.5194/esurf-6-141-2018 2196-6311 2196-632X https://doaj.org/article/e6cb2028387648ab812438a28a4f3e70 |
op_doi |
https://doi.org/10.5194/esurf-6-141-2018 |
container_title |
Earth Surface Dynamics |
container_volume |
6 |
container_issue |
1 |
container_start_page |
141 |
op_container_end_page |
161 |
_version_ |
1766328809483665408 |