A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway
The exchange of shallow and deep water masses between the Indian Ocean and the Atlantic constitutes an integral inter-ocean link in the global thermohaline circulation. In the gateway south of South Africa long-term changes in deep water flow during the Cenozoic have been initially studied using ref...
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Deutsche Mineralogische Gesellschaft (DMG) and the Deutsche Geologische Gesellschaft – Geologische Vereinigung (DGGV)
2017
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Online Access: | https://epic.awi.de/id/eprint/45346/ https://epic.awi.de/id/eprint/45346/1/A-314.pdf https://hdl.handle.net/10013/epic.51520 https://hdl.handle.net/10013/epic.51520.d001 |
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ftawi:oai:epic.awi.de:45346 2024-09-15T17:49:16+00:00 A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway Gruetzner, Jens Jiménez-Espejo, Francisco Lathika, Nambiyathodi Uenzelmann-Neben, Gabriele 2017-09 application/pdf https://epic.awi.de/id/eprint/45346/ https://epic.awi.de/id/eprint/45346/1/A-314.pdf https://hdl.handle.net/10013/epic.51520 https://hdl.handle.net/10013/epic.51520.d001 unknown Deutsche Mineralogische Gesellschaft (DMG) and the Deutsche Geologische Gesellschaft – Geologische Vereinigung (DGGV) https://epic.awi.de/id/eprint/45346/1/A-314.pdf https://hdl.handle.net/10013/epic.51520.d001 Gruetzner, J. orcid:0000-0001-5445-2393 , Jiménez-Espejo, F. , Lathika, N. and Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , IODP Expedition 361 Scientists (2017) A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway , GeoBremen 2017, Joint Meeting of DGGV and DMG, Bremen, 24 September 2017 - 29 September 2017 . hdl:10013/epic.51520 EPIC3GeoBremen 2017, Joint Meeting of DGGV and DMG, Bremen, 2017-09-24-2017-09-29Germany, Deutsche Mineralogische Gesellschaft (DMG) and the Deutsche Geologische Gesellschaft – Geologische Vereinigung (DGGV) Conference notRev 2017 ftawi 2024-06-24T04:18:50Z The exchange of shallow and deep water masses between the Indian Ocean and the Atlantic constitutes an integral inter-ocean link in the global thermohaline circulation. In the gateway south of South Africa long-term changes in deep water flow during the Cenozoic have been initially studied using reflection seismic profiles. But the seismic stratigraphy was poorly constrained and not further resolved within the time period from the late Miocene to present. In particular, there were limited Pliocene records that could be used to investigate the influence of climatic (e.g. Antartic ice volume) and tectonic (e.g. closure of the central American seaway) on the deep-water variability. In 2016 the International Ocean Discovery Program (IODP) Expedition 361 (“SAFARI”) drilled on the southeast African margin and in the Indian-Atlantic ocean gateway. The expedition was mainly targeted to reconstruct the history of the greater Agulhas Current system and recovered complete high-resolution Plio-/Pleistocene sediment sections at six drilling locations. Here we present preliminary results from Site U1475 (Agulhas Plateau), a location proximal to the entrance of North Atlantic Deep Water (NADW) to the Southern Ocean and South Indian Ocean. The site is located over a sediment drift in 2669 m water depth and comprises a complete stratigraphic section of the last ∼7 Ma. We show cleaned, edited, and spliced high-resolution data sets of sediment physical properties measured at Site U1475. While the velocity and density records are used to calculate synthetic seismograms for a detailed correlation of the drilling results with the site survey seismic reflection profiles, colour reflectance and natural gamma radiation are interpreted as indicators of biogenic vs. terrigenous sediment input. Preliminary age assignments based on the shipboard bio- and magnetostratigraphy for the most prominent reflectors are ~2.0, ~3.8, and ~5.1 Ma. Furthermore rhythmic bedding within a Pliocene mudwave sequence likely reflects the 100-kyr orbital cycle. ... Conference Object antartic* NADW North Atlantic Deep Water North Atlantic Southern Ocean Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
The exchange of shallow and deep water masses between the Indian Ocean and the Atlantic constitutes an integral inter-ocean link in the global thermohaline circulation. In the gateway south of South Africa long-term changes in deep water flow during the Cenozoic have been initially studied using reflection seismic profiles. But the seismic stratigraphy was poorly constrained and not further resolved within the time period from the late Miocene to present. In particular, there were limited Pliocene records that could be used to investigate the influence of climatic (e.g. Antartic ice volume) and tectonic (e.g. closure of the central American seaway) on the deep-water variability. In 2016 the International Ocean Discovery Program (IODP) Expedition 361 (“SAFARI”) drilled on the southeast African margin and in the Indian-Atlantic ocean gateway. The expedition was mainly targeted to reconstruct the history of the greater Agulhas Current system and recovered complete high-resolution Plio-/Pleistocene sediment sections at six drilling locations. Here we present preliminary results from Site U1475 (Agulhas Plateau), a location proximal to the entrance of North Atlantic Deep Water (NADW) to the Southern Ocean and South Indian Ocean. The site is located over a sediment drift in 2669 m water depth and comprises a complete stratigraphic section of the last ∼7 Ma. We show cleaned, edited, and spliced high-resolution data sets of sediment physical properties measured at Site U1475. While the velocity and density records are used to calculate synthetic seismograms for a detailed correlation of the drilling results with the site survey seismic reflection profiles, colour reflectance and natural gamma radiation are interpreted as indicators of biogenic vs. terrigenous sediment input. Preliminary age assignments based on the shipboard bio- and magnetostratigraphy for the most prominent reflectors are ~2.0, ~3.8, and ~5.1 Ma. Furthermore rhythmic bedding within a Pliocene mudwave sequence likely reflects the 100-kyr orbital cycle. ... |
format |
Conference Object |
author |
Gruetzner, Jens Jiménez-Espejo, Francisco Lathika, Nambiyathodi Uenzelmann-Neben, Gabriele |
spellingShingle |
Gruetzner, Jens Jiménez-Espejo, Francisco Lathika, Nambiyathodi Uenzelmann-Neben, Gabriele A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
author_facet |
Gruetzner, Jens Jiménez-Espejo, Francisco Lathika, Nambiyathodi Uenzelmann-Neben, Gabriele |
author_sort |
Gruetzner, Jens |
title |
A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
title_short |
A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
title_full |
A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
title_fullStr |
A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
title_full_unstemmed |
A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway |
title_sort |
new seismic stratigraphy for the plio-/pleistocene at the agulhas plateau related to the variability of sediment provenance in the indian-atlantic ocean gateway |
publisher |
Deutsche Mineralogische Gesellschaft (DMG) and the Deutsche Geologische Gesellschaft – Geologische Vereinigung (DGGV) |
publishDate |
2017 |
url |
https://epic.awi.de/id/eprint/45346/ https://epic.awi.de/id/eprint/45346/1/A-314.pdf https://hdl.handle.net/10013/epic.51520 https://hdl.handle.net/10013/epic.51520.d001 |
genre |
antartic* NADW North Atlantic Deep Water North Atlantic Southern Ocean |
genre_facet |
antartic* NADW North Atlantic Deep Water North Atlantic Southern Ocean |
op_source |
EPIC3GeoBremen 2017, Joint Meeting of DGGV and DMG, Bremen, 2017-09-24-2017-09-29Germany, Deutsche Mineralogische Gesellschaft (DMG) and the Deutsche Geologische Gesellschaft – Geologische Vereinigung (DGGV) |
op_relation |
https://epic.awi.de/id/eprint/45346/1/A-314.pdf https://hdl.handle.net/10013/epic.51520.d001 Gruetzner, J. orcid:0000-0001-5445-2393 , Jiménez-Espejo, F. , Lathika, N. and Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , IODP Expedition 361 Scientists (2017) A new seismic stratigraphy for the Plio-/Pleistocene at the Agulhas Plateau related to the variability of sediment provenance in the Indian-Atlantic Ocean gateway , GeoBremen 2017, Joint Meeting of DGGV and DMG, Bremen, 24 September 2017 - 29 September 2017 . hdl:10013/epic.51520 |
_version_ |
1810291035068170240 |