Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia
High-resolution analyses of rock magnetic and sedimentological parameters were conducted on an 11 m long sediment core from Lama Lake, Northern Siberia, which encompasses the late Pleistocene and the Holocene epochs. The results reveal a strong link between the median grain size of the magnetic part...
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2001
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.788417 2023-05-15T15:14:52+02:00 Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia Nowaczyk, Norbert R Harwart, Stefanie K Melles, Martin LATITUDE: 69.548000 * LONGITUDE: 90.211000 * DATE/TIME START: 1993-01-01T00:00:00 * DATE/TIME END: 1993-01-01T00:00:00 2001-09-10 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.788417 https://doi.org/10.1594/PANGAEA.788417 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.788417 https://doi.org/10.1594/PANGAEA.788417 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Nowaczyk, Norbert R; Harwart, Stefanie K; Melles, Martin (2001): Impact of early diagenesis and bulk particle grain size distribution on estimates of relative geomagnetic paleointensity variations in sediments from Lama Lake, northern Central Siberia. Geophysical Journal International, 145(1), 300-306, https://doi.org/10.1046/j.0956-540x.2001.01388.x AWI_PerDyn AWI Arctic Land Expedition COMPCORE Composite Core GeoForschungszentrum Potsdam GFZ Norilsk/Taymyr Sibiria Norilsk/Taymyr93 Permafrost Research (Periglacial Dynamics) @ AWI PG1111 Quaternary Environment of the Eurasian North QUEEN RU-Land_1993_Norilsk_Taymyr Dataset 2001 ftpangaea https://doi.org/10.1594/PANGAEA.788417 https://doi.org/10.1046/j.0956-540x.2001.01388.x 2023-01-20T07:32:42Z High-resolution analyses of rock magnetic and sedimentological parameters were conducted on an 11 m long sediment core from Lama Lake, Northern Siberia, which encompasses the late Pleistocene and the Holocene epochs. The results reveal a strong link between the median grain size of the magnetic particles, identified as magnetite, and the oxidation state of the sediment. Reducing conditions associated with a relative high total organic carbon (TOC) content of the sediment characterize the upper 7 m of the core (~ Holocene), and these have led to a partial dissolution of detrital magnetite grains, and a homogenization of grain-size-related rock magnetic parameters. The anoxic sediments are characterized by significantly larger median magnetic grain sizes, as indicated, for example, by lower median destructive fields of the natural remanent magnetization (MDFNRM) and lower ratios of saturation remanence to saturation magnetization (MSR/MS). Consequently, estimates of relative geomagnetic palaeointensity variations yielded large amplitude shifts associated with anoxic/oxic boundaries. Despite the partial reductive dissolution of magnetic particles within the anoxic section, and consequent minimal variations in magnetic concentration and grain size, palaeointensity estimates for this part of the core were still lithologically distorted by the effects of particle size (and subsidiary TOC) variations. Anomalously high values coincide with an interval of significantly more fine-grained sediment, which is also associated with a decrease in TOC content, which may thus imply a decreased level of magnetite dissolution in this interval. Calculation of relative palaeointensity estimates therefore seems to be compromised by a combined effect of shifts in the particle size distribution of the bulk sediment and by partial magnetite dissolution varying in association with the TOC content of the sediment. Dataset Arctic norilsk permafrost Taymyr Siberia PANGAEA - Data Publisher for Earth & Environmental Science Arctic Norilsk ENVELOPE(88.203,88.203,69.354,69.354) Taymyr ENVELOPE(89.987,89.987,68.219,68.219) ENVELOPE(90.211000,90.211000,69.548000,69.548000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
AWI_PerDyn AWI Arctic Land Expedition COMPCORE Composite Core GeoForschungszentrum Potsdam GFZ Norilsk/Taymyr Sibiria Norilsk/Taymyr93 Permafrost Research (Periglacial Dynamics) @ AWI PG1111 Quaternary Environment of the Eurasian North QUEEN RU-Land_1993_Norilsk_Taymyr |
spellingShingle |
AWI_PerDyn AWI Arctic Land Expedition COMPCORE Composite Core GeoForschungszentrum Potsdam GFZ Norilsk/Taymyr Sibiria Norilsk/Taymyr93 Permafrost Research (Periglacial Dynamics) @ AWI PG1111 Quaternary Environment of the Eurasian North QUEEN RU-Land_1993_Norilsk_Taymyr Nowaczyk, Norbert R Harwart, Stefanie K Melles, Martin Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
topic_facet |
AWI_PerDyn AWI Arctic Land Expedition COMPCORE Composite Core GeoForschungszentrum Potsdam GFZ Norilsk/Taymyr Sibiria Norilsk/Taymyr93 Permafrost Research (Periglacial Dynamics) @ AWI PG1111 Quaternary Environment of the Eurasian North QUEEN RU-Land_1993_Norilsk_Taymyr |
description |
High-resolution analyses of rock magnetic and sedimentological parameters were conducted on an 11 m long sediment core from Lama Lake, Northern Siberia, which encompasses the late Pleistocene and the Holocene epochs. The results reveal a strong link between the median grain size of the magnetic particles, identified as magnetite, and the oxidation state of the sediment. Reducing conditions associated with a relative high total organic carbon (TOC) content of the sediment characterize the upper 7 m of the core (~ Holocene), and these have led to a partial dissolution of detrital magnetite grains, and a homogenization of grain-size-related rock magnetic parameters. The anoxic sediments are characterized by significantly larger median magnetic grain sizes, as indicated, for example, by lower median destructive fields of the natural remanent magnetization (MDFNRM) and lower ratios of saturation remanence to saturation magnetization (MSR/MS). Consequently, estimates of relative geomagnetic palaeointensity variations yielded large amplitude shifts associated with anoxic/oxic boundaries. Despite the partial reductive dissolution of magnetic particles within the anoxic section, and consequent minimal variations in magnetic concentration and grain size, palaeointensity estimates for this part of the core were still lithologically distorted by the effects of particle size (and subsidiary TOC) variations. Anomalously high values coincide with an interval of significantly more fine-grained sediment, which is also associated with a decrease in TOC content, which may thus imply a decreased level of magnetite dissolution in this interval. Calculation of relative palaeointensity estimates therefore seems to be compromised by a combined effect of shifts in the particle size distribution of the bulk sediment and by partial magnetite dissolution varying in association with the TOC content of the sediment. |
format |
Dataset |
author |
Nowaczyk, Norbert R Harwart, Stefanie K Melles, Martin |
author_facet |
Nowaczyk, Norbert R Harwart, Stefanie K Melles, Martin |
author_sort |
Nowaczyk, Norbert R |
title |
Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
title_short |
Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
title_full |
Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
title_fullStr |
Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
title_full_unstemmed |
Paleointensities of sediment core PG1111, Lama Lake, northern Central Siberia |
title_sort |
paleointensities of sediment core pg1111, lama lake, northern central siberia |
publisher |
PANGAEA |
publishDate |
2001 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.788417 https://doi.org/10.1594/PANGAEA.788417 |
op_coverage |
LATITUDE: 69.548000 * LONGITUDE: 90.211000 * DATE/TIME START: 1993-01-01T00:00:00 * DATE/TIME END: 1993-01-01T00:00:00 |
long_lat |
ENVELOPE(88.203,88.203,69.354,69.354) ENVELOPE(89.987,89.987,68.219,68.219) ENVELOPE(90.211000,90.211000,69.548000,69.548000) |
geographic |
Arctic Norilsk Taymyr |
geographic_facet |
Arctic Norilsk Taymyr |
genre |
Arctic norilsk permafrost Taymyr Siberia |
genre_facet |
Arctic norilsk permafrost Taymyr Siberia |
op_source |
Supplement to: Nowaczyk, Norbert R; Harwart, Stefanie K; Melles, Martin (2001): Impact of early diagenesis and bulk particle grain size distribution on estimates of relative geomagnetic paleointensity variations in sediments from Lama Lake, northern Central Siberia. Geophysical Journal International, 145(1), 300-306, https://doi.org/10.1046/j.0956-540x.2001.01388.x |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.788417 https://doi.org/10.1594/PANGAEA.788417 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.788417 https://doi.org/10.1046/j.0956-540x.2001.01388.x |
_version_ |
1766345275477065728 |