Calcite saturation and dissolution index of core-top sediment samples from the Ontong Java Plateau, Mid-Atlantic Ridge, the Caribbean and the Ceara Rise, the Indian Ocean, the Ninety-East Ridge and from the east of Madagascar
Fuente:
PANGAEA
Salvato in:
| Autori principali: | , , , |
|---|---|
| Natura: | Dataset Open Access |
| Lingua: | en |
| Pubblicazione: |
PANGAEA
2010
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1867169502834196480 |
|---|---|
| author | Johnstone, Heather J H Schulz, Michael Barker, Stephen Elderfield, Henry |
| author_facet | Johnstone, Heather J H Schulz, Michael Barker, Stephen Elderfield, Henry |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | X-ray computed tomography (CT) provides an insight into the progression of dissolution in the tests of planktonic foraminifera. Four species of foraminifera (G. ruber [white], G. sacculifer, N. dutertrei and P. obliquiloculata) from Pacific, Atlantic and Indian Ocean core-top samples were examined by CT and SEM. Inner chamber walls began to dissolve at Delta[CO3**2-] values of 12-14 µmol/kg. Close to the calcite saturation horizon, dissolution and precipitation of calcite may occur simultaneously. Inner calcite of G. sacculifer, N. dutertrei and P. obliquiloculata from such sites appeared altered or replaced, whereas outer crust calcite was dense with no pores. Unlike the other species, there was no distinction between inner and outer calcite in CT scans of G. ruber. Empty calcite crusts of N. dutertrei and P. obliquiloculata were most resistant to dissolution and were present in samples where Delta[CO3**2-] ~ -20 µmol/kg. Five stages of preservation were identified in CT scans, and an empirical dissolution index, XDX, was established. XDX appears to be insensitive to initial test mass. Mass loss in response to dissolution was similar between species and sites at ~ 0.4 µg/µmol/kg. We provide calibrations to estimate Delta[CO3**2-] and initial test mass from XDX. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_756133 |
| institution | PANGAEA |
| language | en |
| publishDate | 2010 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Calcite saturation and dissolution index of core-top sediment samples from the Ontong Java Plateau, Mid-Atlantic Ridge, the Caribbean and the Ceara Rise, the Indian Ocean, the Ninety-East Ridge and from the east of Madagascar Johnstone, Heather J H Schulz, Michael Barker, Stephen Elderfield, Henry BC; Box corer; Brazil Basin; CD129; Ceara Rise; Center for Marine Environmental Sciences; Charles Darwin; GeoB1503-2; GeoB4403-1; GeoB4406-2; GeoB4413-1; GeoB4415-2; GeoB4416-2; GeoB4420-1; GeoB4421-2; GeoB4424-2; Giant box corer; GKG; M16/2; M35/1; M35010-3; M35014-2; M35024-7; M35026-1; M38/2; MARUM; Meteor (1986); Mid Atlantic Ridge; Moana Wave; MUC; MultiCorer; MW9109; MW9109-13BC; MW9109-16BC; MW9109-22BC; MW9109-33BC; MW9109-37BC; MW9109-3BC; MW9109-51BC; MW9109-53BC; MW9109-54BC; MW9109-58BC; MW9109-66BC; MW9109-74BC; Ontong Java Plateau; Pacific; PC; Piston corer; RC14; RC14-31; RC14-33; Robert Conrad; V29; V29-9; Vema; West Indian Ocean; WIND; WIND-10B; WIND-11B; WIND-12B; WIND-13B; WIND-20B; WIND-23B; WIND-25B; WIND-28B; WIND-33B; WIND-5B; WIND-6B X-ray computed tomography (CT) provides an insight into the progression of dissolution in the tests of planktonic foraminifera. Four species of foraminifera (G. ruber [white], G. sacculifer, N. dutertrei and P. obliquiloculata) from Pacific, Atlantic and Indian Ocean core-top samples were examined by CT and SEM. Inner chamber walls began to dissolve at Delta[CO3**2-] values of 12-14 µmol/kg. Close to the calcite saturation horizon, dissolution and precipitation of calcite may occur simultaneously. Inner calcite of G. sacculifer, N. dutertrei and P. obliquiloculata from such sites appeared altered or replaced, whereas outer crust calcite was dense with no pores. Unlike the other species, there was no distinction between inner and outer calcite in CT scans of G. ruber. Empty calcite crusts of N. dutertrei and P. obliquiloculata were most resistant to dissolution and were present in samples where Delta[CO3**2-] ~ -20 µmol/kg. Five stages of preservation were identified in CT scans, and an empirical dissolution index, XDX, was established. XDX appears to be insensitive to initial test mass. Mass loss in response to dissolution was similar between species and sites at ~ 0.4 µg/µmol/kg. We provide calibrations to estimate Delta[CO3**2-] and initial test mass from XDX. |
| title | Calcite saturation and dissolution index of core-top sediment samples from the Ontong Java Plateau, Mid-Atlantic Ridge, the Caribbean and the Ceara Rise, the Indian Ocean, the Ninety-East Ridge and from the east of Madagascar |
| topic | BC; Box corer; Brazil Basin; CD129; Ceara Rise; Center for Marine Environmental Sciences; Charles Darwin; GeoB1503-2; GeoB4403-1; GeoB4406-2; GeoB4413-1; GeoB4415-2; GeoB4416-2; GeoB4420-1; GeoB4421-2; GeoB4424-2; Giant box corer; GKG; M16/2; M35/1; M35010-3; M35014-2; M35024-7; M35026-1; M38/2; MARUM; Meteor (1986); Mid Atlantic Ridge; Moana Wave; MUC; MultiCorer; MW9109; MW9109-13BC; MW9109-16BC; MW9109-22BC; MW9109-33BC; MW9109-37BC; MW9109-3BC; MW9109-51BC; MW9109-53BC; MW9109-54BC; MW9109-58BC; MW9109-66BC; MW9109-74BC; Ontong Java Plateau; Pacific; PC; Piston corer; RC14; RC14-31; RC14-33; Robert Conrad; V29; V29-9; Vema; West Indian Ocean; WIND; WIND-10B; WIND-11B; WIND-12B; WIND-13B; WIND-20B; WIND-23B; WIND-25B; WIND-28B; WIND-33B; WIND-5B; WIND-6B |
| url | https://doi.org/10.1594/PANGAEA.756133 |