The isotope composition of inorganic Germanium in seawater and deep sea sponges
Although dissolved concentrations of germanium (Ge) and silicon (Si) in modern seawater are tightly correlated, uncertainties still exist in the modern marine Ge cycle. Germanium stable isotope systematics in marine systems should provide additional constraints on marine Ge sources and sinks, howeve...
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fttriple:oai:gotriple.eu:10670/1.q52qbh 2023-05-15T16:02:34+02:00 The isotope composition of inorganic Germanium in seawater and deep sea sponges Guillermic, Maxence Lalonde, Stefan Hendry, Katharine R. Rouxel, Olivier https://doi.org/10.1016/j.gca.2017.06.011 https://archimer.ifremer.fr/doc/00388/49956/50529.pdf https://archimer.ifremer.fr/doc/00388/49956/ en eng Pergamon-elsevier Science Ltd doi:10.1016/j.gca.2017.06.011 10670/1.q52qbh https://archimer.ifremer.fr/doc/00388/49956/50529.pdf https://archimer.ifremer.fr/doc/00388/49956/ other Archimer, archive institutionnelle de l'Ifremer Geochimica Et Cosmochimica Acta (0016-7037) (Pergamon-elsevier Science Ltd), 2017-09 , Vol. 212 , P. 99-118 envir geo Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ fttriple https://doi.org/10.1016/j.gca.2017.06.011 2023-01-22T17:05:16Z Although dissolved concentrations of germanium (Ge) and silicon (Si) in modern seawater are tightly correlated, uncertainties still exist in the modern marine Ge cycle. Germanium stable isotope systematics in marine systems should provide additional constraints on marine Ge sources and sinks, however the low concentration of Ge in seawater presents an analytical challenge for isotopic measurement. Here, we present a new method of pre-concentration of inorganic Ge from seawater which was applied to measure three Ge isotope profiles in the Southern Ocean and deep seawater from the Atlantic and Pacific Oceans. Germanium isotopic measurements were performed on Ge amounts as low as 2.6 ng using a double-spike approach and a hydride generation system coupled to a MC-ICP-MS. Germanium was co-precipitated with iron hydroxide and then purified through anion-exchange chromatography. Results for the deep (i.e. > 1000 m depth) Pacific Ocean off Hawaii (nearby Loihi Seamount) and the deep Atlantic off Bermuda (BATS station) showed nearly identical δ74/70Ge values at 3.19 ± 0.31 ‰ (2SD, n = 9) and 2.93 ± 0.10 ‰ (2SD, n = 2), respectively. Vertical distributions of Ge concentration and isotope composition in the deep Southern Ocean for water depth > 1300 m yielded an average δ74/70Ge = 3.13 ± 0.25 ‰ (2SD, n = 14) and Ge/Si = 0.80 ± 0.09 μmol/mol (2SD, n = 12). Significant variations in δ74/70Ge, from 2.62 to 3.71 ‰, were measured in the first 1000 m in one station of the Southern Ocean near Sars Seamount in the Drake Passage, with the heaviest values measured in surface waters. Isotope fractionation by diatoms during opal biomineralization may explain the enrichment in heavy isotopes for both Ge and Si in surface seawater. However, examination of both oceanographic parameters and δ74/70Ge values suggest also that water mass mixing and potential contribution of shelf-derived Ge also could contribute to the variations. Combining these results with new Ge isotope data for deep-sea sponges sampled nearby allowed us to ... Text Drake Passage Southern Ocean Unknown Drake Passage Pacific Sars Seamount ENVELOPE(-69.000,-69.000,-59.583,-59.583) Southern Ocean Geochimica et Cosmochimica Acta 212 99 118 |
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English |
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envir geo |
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envir geo Guillermic, Maxence Lalonde, Stefan Hendry, Katharine R. Rouxel, Olivier The isotope composition of inorganic Germanium in seawater and deep sea sponges |
topic_facet |
envir geo |
description |
Although dissolved concentrations of germanium (Ge) and silicon (Si) in modern seawater are tightly correlated, uncertainties still exist in the modern marine Ge cycle. Germanium stable isotope systematics in marine systems should provide additional constraints on marine Ge sources and sinks, however the low concentration of Ge in seawater presents an analytical challenge for isotopic measurement. Here, we present a new method of pre-concentration of inorganic Ge from seawater which was applied to measure three Ge isotope profiles in the Southern Ocean and deep seawater from the Atlantic and Pacific Oceans. Germanium isotopic measurements were performed on Ge amounts as low as 2.6 ng using a double-spike approach and a hydride generation system coupled to a MC-ICP-MS. Germanium was co-precipitated with iron hydroxide and then purified through anion-exchange chromatography. Results for the deep (i.e. > 1000 m depth) Pacific Ocean off Hawaii (nearby Loihi Seamount) and the deep Atlantic off Bermuda (BATS station) showed nearly identical δ74/70Ge values at 3.19 ± 0.31 ‰ (2SD, n = 9) and 2.93 ± 0.10 ‰ (2SD, n = 2), respectively. Vertical distributions of Ge concentration and isotope composition in the deep Southern Ocean for water depth > 1300 m yielded an average δ74/70Ge = 3.13 ± 0.25 ‰ (2SD, n = 14) and Ge/Si = 0.80 ± 0.09 μmol/mol (2SD, n = 12). Significant variations in δ74/70Ge, from 2.62 to 3.71 ‰, were measured in the first 1000 m in one station of the Southern Ocean near Sars Seamount in the Drake Passage, with the heaviest values measured in surface waters. Isotope fractionation by diatoms during opal biomineralization may explain the enrichment in heavy isotopes for both Ge and Si in surface seawater. However, examination of both oceanographic parameters and δ74/70Ge values suggest also that water mass mixing and potential contribution of shelf-derived Ge also could contribute to the variations. Combining these results with new Ge isotope data for deep-sea sponges sampled nearby allowed us to ... |
format |
Text |
author |
Guillermic, Maxence Lalonde, Stefan Hendry, Katharine R. Rouxel, Olivier |
author_facet |
Guillermic, Maxence Lalonde, Stefan Hendry, Katharine R. Rouxel, Olivier |
author_sort |
Guillermic, Maxence |
title |
The isotope composition of inorganic Germanium in seawater and deep sea sponges |
title_short |
The isotope composition of inorganic Germanium in seawater and deep sea sponges |
title_full |
The isotope composition of inorganic Germanium in seawater and deep sea sponges |
title_fullStr |
The isotope composition of inorganic Germanium in seawater and deep sea sponges |
title_full_unstemmed |
The isotope composition of inorganic Germanium in seawater and deep sea sponges |
title_sort |
isotope composition of inorganic germanium in seawater and deep sea sponges |
publisher |
Pergamon-elsevier Science Ltd |
url |
https://doi.org/10.1016/j.gca.2017.06.011 https://archimer.ifremer.fr/doc/00388/49956/50529.pdf https://archimer.ifremer.fr/doc/00388/49956/ |
long_lat |
ENVELOPE(-69.000,-69.000,-59.583,-59.583) |
geographic |
Drake Passage Pacific Sars Seamount Southern Ocean |
geographic_facet |
Drake Passage Pacific Sars Seamount Southern Ocean |
genre |
Drake Passage Southern Ocean |
genre_facet |
Drake Passage Southern Ocean |
op_source |
Archimer, archive institutionnelle de l'Ifremer Geochimica Et Cosmochimica Acta (0016-7037) (Pergamon-elsevier Science Ltd), 2017-09 , Vol. 212 , P. 99-118 |
op_relation |
doi:10.1016/j.gca.2017.06.011 10670/1.q52qbh https://archimer.ifremer.fr/doc/00388/49956/50529.pdf https://archimer.ifremer.fr/doc/00388/49956/ |
op_rights |
other |
op_doi |
https://doi.org/10.1016/j.gca.2017.06.011 |
container_title |
Geochimica et Cosmochimica Acta |
container_volume |
212 |
container_start_page |
99 |
op_container_end_page |
118 |
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1766398239908560896 |