Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D
Dansgaard-Oeschger (D-O) cycles in sediment at Site 1063 are characterized by distinct fluctuations in physical properties. Stadials are marked by low bulk density and interstadials by high bulk density. Compressional (P-)wave velocity is in phase with bulk density over some but not all depth interv...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.787968 2024-09-15T18:24:03+00:00 Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D Dunbar, Gavin B LATITUDE: 33.686190 * LONGITUDE: -57.615110 * DATE/TIME START: 1997-04-01T06:20:00 * DATE/TIME END: 1997-04-01T06:20:00 2001 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.787968 https://doi.org/10.1594/PANGAEA.787968 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.787968 https://doi.org/10.1594/PANGAEA.787968 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Dunbar, Gavin B (2001): A detailed characterization of Dansgaard-Oeschger cycles at Site 1063 (Bermuda Rise). In: Keigwin, LD; Rio, D; Acton, GD; Arnold, E (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 172, 1-24, https://doi.org/10.2973/odp.proc.sr.172.215.2001 172-1063D DRILL Drilling/drill rig Joides Resolution Leg172 North Atlantic Ocean Ocean Drilling Program ODP dataset publication series 2001 ftpangaea https://doi.org/10.1594/PANGAEA.78796810.2973/odp.proc.sr.172.215.2001 2024-08-21T00:02:25Z Dansgaard-Oeschger (D-O) cycles in sediment at Site 1063 are characterized by distinct fluctuations in physical properties. Stadials are marked by low bulk density and interstadials by high bulk density. Compressional (P-)wave velocity is in phase with bulk density over some but not all depth intervals. Four of the D-O cycles straddling the oxygen isotope Stage 4/5 boundary have been studied in detail to understand the origin of the physical properties changes. Sediment on the Bermuda Rise is comprised of three main components: calcite, aluminosilicate minerals, and biogenic silica. Calcite concentrations vary from 1% to 43% of bulk sediment and are highest during interstadials. Aluminosilicate concentrations vary from 52% to 92% of bulk sediment and are highest during stadials. The major element ratios Al2O3/TiO2 and K2O/Al2O3 show increases across bulk density cycles, suggesting a change in the composition of aluminosilicates. This interpretation is supported by mineralogical analyses, which show a subtle change in clay composition. Biogenic silica concentrations vary from 0% to 23% of bulk sediment and are also highest during stadials. However, the abundance of silica varies significantly from one D-O cycle to another. Silt and fine sand abundance also increase during the first of the four stadials. This coarsening of sediment coincides with the increase in biogenic silica. The low grain density and high porosity associated with biogenic silica result in intervals of low bulk-sediment density. The abundance of biogenic silica closely matches P-wave velocity, suggesting that silica imparts a greater rigidity to the sediment. Other/Unknown Material North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-57.615110,-57.615110,33.686190,33.686190) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
172-1063D DRILL Drilling/drill rig Joides Resolution Leg172 North Atlantic Ocean Ocean Drilling Program ODP |
spellingShingle |
172-1063D DRILL Drilling/drill rig Joides Resolution Leg172 North Atlantic Ocean Ocean Drilling Program ODP Dunbar, Gavin B Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
topic_facet |
172-1063D DRILL Drilling/drill rig Joides Resolution Leg172 North Atlantic Ocean Ocean Drilling Program ODP |
description |
Dansgaard-Oeschger (D-O) cycles in sediment at Site 1063 are characterized by distinct fluctuations in physical properties. Stadials are marked by low bulk density and interstadials by high bulk density. Compressional (P-)wave velocity is in phase with bulk density over some but not all depth intervals. Four of the D-O cycles straddling the oxygen isotope Stage 4/5 boundary have been studied in detail to understand the origin of the physical properties changes. Sediment on the Bermuda Rise is comprised of three main components: calcite, aluminosilicate minerals, and biogenic silica. Calcite concentrations vary from 1% to 43% of bulk sediment and are highest during interstadials. Aluminosilicate concentrations vary from 52% to 92% of bulk sediment and are highest during stadials. The major element ratios Al2O3/TiO2 and K2O/Al2O3 show increases across bulk density cycles, suggesting a change in the composition of aluminosilicates. This interpretation is supported by mineralogical analyses, which show a subtle change in clay composition. Biogenic silica concentrations vary from 0% to 23% of bulk sediment and are also highest during stadials. However, the abundance of silica varies significantly from one D-O cycle to another. Silt and fine sand abundance also increase during the first of the four stadials. This coarsening of sediment coincides with the increase in biogenic silica. The low grain density and high porosity associated with biogenic silica result in intervals of low bulk-sediment density. The abundance of biogenic silica closely matches P-wave velocity, suggesting that silica imparts a greater rigidity to the sediment. |
format |
Other/Unknown Material |
author |
Dunbar, Gavin B |
author_facet |
Dunbar, Gavin B |
author_sort |
Dunbar, Gavin B |
title |
Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
title_short |
Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
title_full |
Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
title_fullStr |
Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
title_full_unstemmed |
Mineralogy and major element oxide composition of sediments from ODP Hole 172-1063D |
title_sort |
mineralogy and major element oxide composition of sediments from odp hole 172-1063d |
publisher |
PANGAEA |
publishDate |
2001 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.787968 https://doi.org/10.1594/PANGAEA.787968 |
op_coverage |
LATITUDE: 33.686190 * LONGITUDE: -57.615110 * DATE/TIME START: 1997-04-01T06:20:00 * DATE/TIME END: 1997-04-01T06:20:00 |
long_lat |
ENVELOPE(-57.615110,-57.615110,33.686190,33.686190) |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Supplement to: Dunbar, Gavin B (2001): A detailed characterization of Dansgaard-Oeschger cycles at Site 1063 (Bermuda Rise). In: Keigwin, LD; Rio, D; Acton, GD; Arnold, E (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 172, 1-24, https://doi.org/10.2973/odp.proc.sr.172.215.2001 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.787968 https://doi.org/10.1594/PANGAEA.787968 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.78796810.2973/odp.proc.sr.172.215.2001 |
_version_ |
1810464354891464704 |