Gespeichert in:
| Hauptverfasser: | , , , , |
|---|---|
| Format: | Dataset Open Access |
| Sprache: | en |
| Veröffentlicht: |
PANGAEA
2000
|
| Schlagworte: | |
| Online-Zugang: | https://doi.org/10.1594/PANGAEA.713007 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1867170455430889472 |
|---|---|
| author | Vonhof, Hubert B Smit, Jan Brinkhuis, Henk Montanari, Alessandro Nederbragt, Alexandra J |
| author_facet | Vonhof, Hubert B Smit, Jan Brinkhuis, Henk Montanari, Alessandro Nederbragt, Alexandra J |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | At Ocean Drilling Program Site 689 (Maud Rise, Southern Ocean), d18O records of fine-fraction bulk carbonate and benthic foraminifers indicate that accelerated climate cooling took place following at least two closely spaced early late Eocene extraterrestrial impact events. A simultaneous surface-water productivity increase, as interpreted from d13C data, is explained by enhanced water-column mixing due to increased latitudinal temperature gradients. These isotope data appear to be in concert with organic-walled dinoflagellate-cyst records across the same microkrystite-bearing impact-ejecta layer in the mid-latitude Massignano section (central Italy). In particular, the strong abundance increase of Thalassiphora pelagica is interpreted to indicate cooling or increased productivity at Massignano. Because impact-induced cooling processes are active on time scales of a few years at most, the estimated 100 k.y. duration of the cooling event appears to be too long to be explained by impact scenarios alone. This implies that a feedback mechanism, such as a global albedo increase due to extended snow and ice cover, may have sustained impact-induced cooling for a longer time after the impacts. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_713007 |
| institution | PANGAEA |
| language | en |
| publishDate | 2000 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Carbon and oxygen isotope data for carbonates and benthic foraminifers from ODP Hole 113-689B Vonhof, Hubert B Smit, Jan Brinkhuis, Henk Montanari, Alessandro Nederbragt, Alexandra J 113-689B; DRILL; Drilling/drill rig; Joides Resolution; Leg113; Ocean Drilling Program; ODP; South Atlantic Ocean At Ocean Drilling Program Site 689 (Maud Rise, Southern Ocean), d18O records of fine-fraction bulk carbonate and benthic foraminifers indicate that accelerated climate cooling took place following at least two closely spaced early late Eocene extraterrestrial impact events. A simultaneous surface-water productivity increase, as interpreted from d13C data, is explained by enhanced water-column mixing due to increased latitudinal temperature gradients. These isotope data appear to be in concert with organic-walled dinoflagellate-cyst records across the same microkrystite-bearing impact-ejecta layer in the mid-latitude Massignano section (central Italy). In particular, the strong abundance increase of Thalassiphora pelagica is interpreted to indicate cooling or increased productivity at Massignano. Because impact-induced cooling processes are active on time scales of a few years at most, the estimated 100 k.y. duration of the cooling event appears to be too long to be explained by impact scenarios alone. This implies that a feedback mechanism, such as a global albedo increase due to extended snow and ice cover, may have sustained impact-induced cooling for a longer time after the impacts. |
| title | Carbon and oxygen isotope data for carbonates and benthic foraminifers from ODP Hole 113-689B |
| topic | 113-689B; DRILL; Drilling/drill rig; Joides Resolution; Leg113; Ocean Drilling Program; ODP; South Atlantic Ocean |
| url | https://doi.org/10.1594/PANGAEA.713007 |