Calcium isotope ratios of pore fluids and solid phase of organic rich sediments
Pore fluid calcium isotope, calcium concentration and strontium concentration data are used to measure the rates of diagenetic dissolution and precipitation of calcite in deep-sea sediments containing abundant clay and organic material. This type of study of deep-sea sediment diagenesis provides uni...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.782774 2024-09-15T18:23:21+00:00 Calcium isotope ratios of pore fluids and solid phase of organic rich sediments Turchyn, Alexandra V DePaolo, Donald J MEDIAN LATITUDE: -0.464189 * MEDIAN LONGITUDE: 2.844825 * SOUTH-BOUND LATITUDE: -21.094194 * WEST-BOUND LONGITUDE: -24.082417 * NORTH-BOUND LATITUDE: 61.425317 * EAST-BOUND LONGITUDE: 11.820580 * DATE/TIME START: 1995-07-24T00:00:00 * DATE/TIME END: 1997-09-16T00:05:00 2011 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.782774 https://doi.org/10.1594/PANGAEA.782774 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.782774 https://doi.org/10.1594/PANGAEA.782774 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Turchyn, Alexandra V; DePaolo, Donald J (2011): Calcium isotope evidence for suppression of carbonate dissolution in carbonate-bearing organic-rich sediments. Geochimica et Cosmochimica Acta, 75(22), 7081-7098, https://doi.org/10.1016/j.gca.2011.09.014 162-984 175-1082 175-1082A Benguela Current South Atlantic Ocean COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg162 Leg175 North Atlantic Ocean Ocean Drilling Program ODP dataset publication series 2011 ftpangaea https://doi.org/10.1594/PANGAEA.78277410.1016/j.gca.2011.09.014 2024-08-21T00:02:25Z Pore fluid calcium isotope, calcium concentration and strontium concentration data are used to measure the rates of diagenetic dissolution and precipitation of calcite in deep-sea sediments containing abundant clay and organic material. This type of study of deep-sea sediment diagenesis provides unique information about the ultra-slow chemical reactions that occur in natural marine sediments that affect global geochemical cycles and the preservation of paleo-environmental information in carbonate fossils. For this study, calcium isotope ratios (d44/40Ca) of pore fluid calcium from Ocean Drilling Program (ODP) Sites 984 (North Atlantic) and 1082 (off the coast of West Africa) were measured to augment available pore fluid measurements of calcium and strontium concentration. Both study sites have high sedimentation rates and support quantitative sulfate reduction, methanogenesis and anaerobic methane oxidation. The pattern of change of d44/40Ca of pore fluid calcium versus depth at Sites 984 and 1082 differs markedly from that of previously studied deep-sea Sites like 590B and 807, which are composed of nearly pure carbonate sediment. In the 984 and 1082 pore fluids, d44/40Ca remains elevated near seawater values deep in the sediments, rather than shifting rapidly toward the d44/40Ca of carbonate solids. This observation indicates that the rate of calcite dissolution is far lower than at previously studied carbonate-rich sites. The data are fit using a numerical model, as well as more approximate analytical models, to estimate the rates of carbonate dissolution and precipitation and the relationship of these rates to the abundance of clay and organic material. Our models give mutually consistent results and indicate that calcite dissolution rates at Sites 984 and 1082 are roughly two orders of magnitude lower than at previously studied carbonate-rich sites, and the rate correlates with the abundance of clay. Our calculated rates are conservative for these sites (the actual rates could be significantly slower) ... Other/Unknown Material North Atlantic South Atlantic Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-24.082417,11.820580,61.425317,-21.094194) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
162-984 175-1082 175-1082A Benguela Current South Atlantic Ocean COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg162 Leg175 North Atlantic Ocean Ocean Drilling Program ODP |
spellingShingle |
162-984 175-1082 175-1082A Benguela Current South Atlantic Ocean COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg162 Leg175 North Atlantic Ocean Ocean Drilling Program ODP Turchyn, Alexandra V DePaolo, Donald J Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
topic_facet |
162-984 175-1082 175-1082A Benguela Current South Atlantic Ocean COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg162 Leg175 North Atlantic Ocean Ocean Drilling Program ODP |
description |
Pore fluid calcium isotope, calcium concentration and strontium concentration data are used to measure the rates of diagenetic dissolution and precipitation of calcite in deep-sea sediments containing abundant clay and organic material. This type of study of deep-sea sediment diagenesis provides unique information about the ultra-slow chemical reactions that occur in natural marine sediments that affect global geochemical cycles and the preservation of paleo-environmental information in carbonate fossils. For this study, calcium isotope ratios (d44/40Ca) of pore fluid calcium from Ocean Drilling Program (ODP) Sites 984 (North Atlantic) and 1082 (off the coast of West Africa) were measured to augment available pore fluid measurements of calcium and strontium concentration. Both study sites have high sedimentation rates and support quantitative sulfate reduction, methanogenesis and anaerobic methane oxidation. The pattern of change of d44/40Ca of pore fluid calcium versus depth at Sites 984 and 1082 differs markedly from that of previously studied deep-sea Sites like 590B and 807, which are composed of nearly pure carbonate sediment. In the 984 and 1082 pore fluids, d44/40Ca remains elevated near seawater values deep in the sediments, rather than shifting rapidly toward the d44/40Ca of carbonate solids. This observation indicates that the rate of calcite dissolution is far lower than at previously studied carbonate-rich sites. The data are fit using a numerical model, as well as more approximate analytical models, to estimate the rates of carbonate dissolution and precipitation and the relationship of these rates to the abundance of clay and organic material. Our models give mutually consistent results and indicate that calcite dissolution rates at Sites 984 and 1082 are roughly two orders of magnitude lower than at previously studied carbonate-rich sites, and the rate correlates with the abundance of clay. Our calculated rates are conservative for these sites (the actual rates could be significantly slower) ... |
format |
Other/Unknown Material |
author |
Turchyn, Alexandra V DePaolo, Donald J |
author_facet |
Turchyn, Alexandra V DePaolo, Donald J |
author_sort |
Turchyn, Alexandra V |
title |
Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
title_short |
Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
title_full |
Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
title_fullStr |
Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
title_full_unstemmed |
Calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
title_sort |
calcium isotope ratios of pore fluids and solid phase of organic rich sediments |
publisher |
PANGAEA |
publishDate |
2011 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.782774 https://doi.org/10.1594/PANGAEA.782774 |
op_coverage |
MEDIAN LATITUDE: -0.464189 * MEDIAN LONGITUDE: 2.844825 * SOUTH-BOUND LATITUDE: -21.094194 * WEST-BOUND LONGITUDE: -24.082417 * NORTH-BOUND LATITUDE: 61.425317 * EAST-BOUND LONGITUDE: 11.820580 * DATE/TIME START: 1995-07-24T00:00:00 * DATE/TIME END: 1997-09-16T00:05:00 |
long_lat |
ENVELOPE(-24.082417,11.820580,61.425317,-21.094194) |
genre |
North Atlantic South Atlantic Ocean |
genre_facet |
North Atlantic South Atlantic Ocean |
op_source |
Supplement to: Turchyn, Alexandra V; DePaolo, Donald J (2011): Calcium isotope evidence for suppression of carbonate dissolution in carbonate-bearing organic-rich sediments. Geochimica et Cosmochimica Acta, 75(22), 7081-7098, https://doi.org/10.1016/j.gca.2011.09.014 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.782774 https://doi.org/10.1594/PANGAEA.782774 |
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.78277410.1016/j.gca.2011.09.014 |
_version_ |
1810463539885768704 |