Oligocene to Miocene stable isotope record and planktonic foraminifer biostratigraphy of the Sierra Leone Rise
Fuente:
PANGAEA
Salvato in:
| Autori principali: | , , |
|---|---|
| Natura: | Dataset Open Access |
| Lingua: | en |
| Pubblicazione: |
PANGAEA
1989
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1867170458885947392 |
|---|---|
| author | Miller, Kenneth G Wright, James D Brower, Andrew N |
| author_facet | Miller, Kenneth G Wright, James D Brower, Andrew N |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | We have integrated Oligocene to lower upper Miocene planktonic foraminifer biostratigraphy with benthic foraminifer (Cibicidoides spp.) stable isotope records for two sites drilled on opposite sides of the Sierra Leone Rise in the eastern equatorial Atlantic Ocean. Deep Sea Drilling Project Site 366 (2853 m present water depth; 2200-2800 m paleodepth) recovered an Oligocene to upper Miocene record with a minor unconformity in the "middle" Oligocene and a condensed middle Miocene section. Ocean Drilling Program Site 667 (3529 m present depth; 3000-3500 m paleodepth) recovered an apparently continuous "middle" Oligocene to lower middle Miocene record and a similar condensed middle Miocene section. The Oligocene to lower Miocene sections were deposited at similar sedimentation rates (~11-16 m/m.y.). Stable isotope stratigraphy proved to be useful in establishing intra- and interbasinal correlations. In addition to the well-known earliest Oligocene and middle Miocene S180 increases, a distinct d18O increase occurred near the Oligocene/Miocene boundary. Carbon isotope variations provide similar potential for improving correlations; for example, a d13C increase occurred near the Oligocene/Miocene boundary in concert with increased d18O values. There was little d13C difference between the western Atlantic and eastern Atlantic basins during the late Oligocene and most of the middle Miocene; in contrast, eastern basin d13C values were slightly lower than those in the western basins during the earliest Oligocene (about 35-33 Ma) and early Miocene (about 22-18 Ma). |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_746537 |
| institution | PANGAEA |
| language | en |
| publishDate | 1989 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Oligocene to Miocene stable isotope record and planktonic foraminifer biostratigraphy of the Sierra Leone Rise Miller, Kenneth G Wright, James D Brower, Andrew N 108-667; 108-667A; 41-366; 41-366_Site; 41-366A; COMPCORE; Composite Core; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; Glomar Challenger; Joides Resolution; Leg108; Leg41; North Atlantic/CONT RISE; North Atlantic Ocean; Ocean Drilling Program; ODP We have integrated Oligocene to lower upper Miocene planktonic foraminifer biostratigraphy with benthic foraminifer (Cibicidoides spp.) stable isotope records for two sites drilled on opposite sides of the Sierra Leone Rise in the eastern equatorial Atlantic Ocean. Deep Sea Drilling Project Site 366 (2853 m present water depth; 2200-2800 m paleodepth) recovered an Oligocene to upper Miocene record with a minor unconformity in the "middle" Oligocene and a condensed middle Miocene section. Ocean Drilling Program Site 667 (3529 m present depth; 3000-3500 m paleodepth) recovered an apparently continuous "middle" Oligocene to lower middle Miocene record and a similar condensed middle Miocene section. The Oligocene to lower Miocene sections were deposited at similar sedimentation rates (~11-16 m/m.y.). Stable isotope stratigraphy proved to be useful in establishing intra- and interbasinal correlations. In addition to the well-known earliest Oligocene and middle Miocene S180 increases, a distinct d18O increase occurred near the Oligocene/Miocene boundary. Carbon isotope variations provide similar potential for improving correlations; for example, a d13C increase occurred near the Oligocene/Miocene boundary in concert with increased d18O values. There was little d13C difference between the western Atlantic and eastern Atlantic basins during the late Oligocene and most of the middle Miocene; in contrast, eastern basin d13C values were slightly lower than those in the western basins during the earliest Oligocene (about 35-33 Ma) and early Miocene (about 22-18 Ma). |
| title | Oligocene to Miocene stable isotope record and planktonic foraminifer biostratigraphy of the Sierra Leone Rise |
| topic | 108-667; 108-667A; 41-366; 41-366_Site; 41-366A; COMPCORE; Composite Core; Deep Sea Drilling Project; DRILL; Drilling/drill rig; DSDP; Glomar Challenger; Joides Resolution; Leg108; Leg41; North Atlantic/CONT RISE; North Atlantic Ocean; Ocean Drilling Program; ODP |
| url | https://doi.org/10.1594/PANGAEA.746537 |