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Auteurs principaux: Griffith, Elizabeth M, Paytan, Adina, Kozdon, Reinhard, Eisenhauer, Anton, Ravelo, Ana Christina
Format: Dataset Open Access
Langue:en
Publié: PANGAEA 2016
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Accès en ligne:https://doi.org/10.1594/PANGAEA.858628
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author Griffith, Elizabeth M
Paytan, Adina
Kozdon, Reinhard
Eisenhauer, Anton
Ravelo, Ana Christina
author_facet Griffith, Elizabeth M
Paytan, Adina
Kozdon, Reinhard
Eisenhauer, Anton
Ravelo, Ana Christina
collection Datos científicos de ciencias marinas y ambientales
contents For paleoceanographic studies, it is important to understand the processes that influence the calcium (Ca) isotopic composition of foraminiferal calcite tests preserved in the sediment record. Seven species of planktonic foraminifera from coretop sediments collectively exhibited a Ca temperature dependent fractionation of 0.013 per mil per °C. This is in agreement with previously published estimates for most species of planktonic foraminifera as well as biogenic and inorganic calcite and aragonite. Four species of planktonic foraminifera collected from a sediment trap showed a considerable amount of scatter and no consistent temperature dependent fractionation. Analyzed size fractions of coretop samples show no significant relationship with d44/40Ca. However, preliminary results suggest that the symbiotic and spinose foraminifera G. sacculifer might exhibit a relationship between test size and d44/40Ca. A one-box model in which Ca isotopes are allowed to fractionate by Rayleigh distillation from a biomineralization reservoir (internal pool) was used to constrain the isotopic composition of the original biomineralization Ca reservoir, assuming around 85% of the Ca reservoir is precipitated and the fractionation factor during precipitation is 0.9985 + 0.00002(T ºC). To explain the foraminiferal Ca isotope data, this model indicates that the Ca isotopic composition of the biomineralization reservoir is offset from seawater (approximately -0.8per mil).
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_858628
institution PANGAEA
language en
publishDate 2016
publisher PANGAEA
record_format pangaea
spellingShingle Calcium isotopes in planktonic foraminifera - core tops and sediment trap samples
Griffith, Elizabeth M
Paytan, Adina
Kozdon, Reinhard
Eisenhauer, Anton
Ravelo, Ana Christina
Ocean Drilling Program; ODP
For paleoceanographic studies, it is important to understand the processes that influence the calcium (Ca) isotopic composition of foraminiferal calcite tests preserved in the sediment record. Seven species of planktonic foraminifera from coretop sediments collectively exhibited a Ca temperature dependent fractionation of 0.013 per mil per °C. This is in agreement with previously published estimates for most species of planktonic foraminifera as well as biogenic and inorganic calcite and aragonite. Four species of planktonic foraminifera collected from a sediment trap showed a considerable amount of scatter and no consistent temperature dependent fractionation. Analyzed size fractions of coretop samples show no significant relationship with d44/40Ca. However, preliminary results suggest that the symbiotic and spinose foraminifera G. sacculifer might exhibit a relationship between test size and d44/40Ca. A one-box model in which Ca isotopes are allowed to fractionate by Rayleigh distillation from a biomineralization reservoir (internal pool) was used to constrain the isotopic composition of the original biomineralization Ca reservoir, assuming around 85% of the Ca reservoir is precipitated and the fractionation factor during precipitation is 0.9985 + 0.00002(T ºC). To explain the foraminiferal Ca isotope data, this model indicates that the Ca isotopic composition of the biomineralization reservoir is offset from seawater (approximately -0.8per mil).
title Calcium isotopes in planktonic foraminifera - core tops and sediment trap samples
topic Ocean Drilling Program; ODP
url https://doi.org/10.1594/PANGAEA.858628