Miocene stable isotope record of benthic foraminifera from IODP Site 320-U1336
Fuente:
PANGAEA
Salvato in:
| Autori principali: | , , , |
|---|---|
| Natura: | Dataset Open Access |
| Lingua: | en |
| Pubblicazione: |
PANGAEA
2015
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1867171837558915072 |
|---|---|
| author | Voigt, Janett Hathorne, Ed C Frank, Martin Holbourn, Ann E |
| author_facet | Voigt, Janett Hathorne, Ed C Frank, Martin Holbourn, Ann E |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Stable carbon and oxygen isotopes (d13C and d18O) of foraminiferal tests are amongst the most important tools in paleoceanography but the extent to which recrystallization can alter the isotopic composition of the tests is not well known. Here, we compare three middle Miocene (16–13 Ma) benthic foraminiferal stable isotope records from eastern equatorial Pacific sites with different diagenetic histories to investigate the effect of recrystallization. To test an extreme case, we analyzed stable isotope compositions of benthic foraminifera from Integrated Ocean Drilling Program Site U1336, for which the geochemistry of bulk carbonates and associated pore waters indicate continued diagenetic alteration in sediments > 14.7 Ma. Despite this diagenetic overprinting, the amplitudes and absolute values of the analyzed U1336 stable isotopes agree well with high resolution records from better preserved Sites U1337 and U1338 nearby. Our results suggest that although benthic foraminiferal tests of all three sites show some degree of textural changes due to recrystallization, they have retained their original stable isotope signatures. The good agreement of the benthic foraminiferal stable isotope records demonstrates that recrystallization occurred extremely rapidly (<100 kyr) after deposition. This is confirmed by the preservation of orbital cyclicities in U1336 stable isotope data and d18O values being different to inorganic calcite that would precipitate from U1336 pore waters during late recrystallization. The close similarity of the benthic foraminiferal stable isotope records between the sites allows the well resolved paleo-magnetic results of Site U1336 to be transferred to Sites U1337 and U1338 improving the global Geological Timescale. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_854835 |
| institution | PANGAEA |
| language | en |
| publishDate | 2015 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Miocene stable isotope record of benthic foraminifera from IODP Site 320-U1336 Voigt, Janett Hathorne, Ed C Frank, Martin Holbourn, Ann E 320-U1336; AGE; COMPCORE; Composite Core; Depth, composite revised; DEPTH, sediment/rock; Exp320; Foraminifera, benthic δ13C; Foraminifera, benthic δ18O; Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP; Joides Resolution; Pacific Equatorial Age Transect I; Sample code/label; Species Stable carbon and oxygen isotopes (d13C and d18O) of foraminiferal tests are amongst the most important tools in paleoceanography but the extent to which recrystallization can alter the isotopic composition of the tests is not well known. Here, we compare three middle Miocene (16–13 Ma) benthic foraminiferal stable isotope records from eastern equatorial Pacific sites with different diagenetic histories to investigate the effect of recrystallization. To test an extreme case, we analyzed stable isotope compositions of benthic foraminifera from Integrated Ocean Drilling Program Site U1336, for which the geochemistry of bulk carbonates and associated pore waters indicate continued diagenetic alteration in sediments > 14.7 Ma. Despite this diagenetic overprinting, the amplitudes and absolute values of the analyzed U1336 stable isotopes agree well with high resolution records from better preserved Sites U1337 and U1338 nearby. Our results suggest that although benthic foraminiferal tests of all three sites show some degree of textural changes due to recrystallization, they have retained their original stable isotope signatures. The good agreement of the benthic foraminiferal stable isotope records demonstrates that recrystallization occurred extremely rapidly (<100 kyr) after deposition. This is confirmed by the preservation of orbital cyclicities in U1336 stable isotope data and d18O values being different to inorganic calcite that would precipitate from U1336 pore waters during late recrystallization. The close similarity of the benthic foraminiferal stable isotope records between the sites allows the well resolved paleo-magnetic results of Site U1336 to be transferred to Sites U1337 and U1338 improving the global Geological Timescale. |
| title | Miocene stable isotope record of benthic foraminifera from IODP Site 320-U1336 |
| topic | 320-U1336; AGE; COMPCORE; Composite Core; Depth, composite revised; DEPTH, sediment/rock; Exp320; Foraminifera, benthic δ13C; Foraminifera, benthic δ18O; Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP; Joides Resolution; Pacific Equatorial Age Transect I; Sample code/label; Species |
| url | https://doi.org/10.1594/PANGAEA.854835 |