The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392
The opening of the Southern Ocean gateways has been debated as a key element in the emergence of the Antarctic Circumpolar Current (ACC), crucial for the onset of global Cenozoic cooling (e.g., Sijp et al., 2014, Glob. Planet. Change 119; Voigt et al., 2013, EPSL 369/370). South of Africa, the openi...
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ftawi:oai:epic.awi.de:57041 2023-05-15T13:45:22+02:00 The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 Geldmacher, Joerg Davidson, Peter C Liu, Jia Ichiyama, Yuji Hoernle, Kaj Uenzelmann-Neben, Gabriele Bohaty, Steven M Childress, Laurel B 2022 https://epic.awi.de/id/eprint/57041/ https://hdl.handle.net/10013/epic.4814dfbc-ed94-491e-a318-d371a980f1d3 unknown Geldmacher, J. , Davidson, P. C. , Liu, J. , Ichiyama, Y. , Hoernle, K. , Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Bohaty, S. M. and Childress, L. B. , IODP Expedition 392 Science Party (2022) The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 , DFG ICDP/IOCP Kolloquium, Potsdam, Germany, 1 November 2022 - 3 November 2022 . doi:10.48440/gfz.b103-22074 <https://doi.org/10.48440/gfz.b103-22074> , hdl:10013/epic.4814dfbc-ed94-491e-a318-d371a980f1d3 EPIC3DFG ICDP/IOCP Kolloquium, Potsdam, Germany, 2022-11-01-2022-11-03IODP/ICDP Kolloquium 2022, Abstract Volume, (Scientific Technical Report STR; 22/07) Conference NonPeerReviewed 2022 ftawi https://doi.org/10.48440/gfz.b103-22074 2022-12-12T00:13:23Z The opening of the Southern Ocean gateways has been debated as a key element in the emergence of the Antarctic Circumpolar Current (ACC), crucial for the onset of global Cenozoic cooling (e.g., Sijp et al., 2014, Glob. Planet. Change 119; Voigt et al., 2013, EPSL 369/370). South of Africa, the opening was associated with the formation of several large igneous provinces (LIPs) including the Mozambique Ridge, Agulhas Plateau and the smaller Northeast Georgia Rise and Maud Rise. Plate tectonic reconstructions imply that the latter two were once part of the much greater Agulhas Plateau and were separated by subsequent rifting (Parsaglia et al., 2008, Geophys. J. Int. 174). It is debated whether and to what extent the emplacement of these large volcanic features obstructed the exchange of water masses between the Atlantic and the Indian Ocean thereby delaying the onset of the ACC. The Agulhas Plateau was drilled during recent IODP Expedition 392 (Uenzelmann-Neben, Bohaty, Childress, et al., IODP Exp. 392 Preliminary Report, 2022, in press). Igneous rocks were recovered at two sites on the southern part of the plateau (Sites U1579, U1580) and at one site near its northern edge (U1582). Preliminary (shipboard) data indicate that all sites returned tholeiitic basalts, formed by low pressure (shallow magma chamber) fractionation of mainly olivine and plagioclase (as typical for mid-ocean ridge basalts and many LIP lavas). 40Ar/39Ar dating will help to answer fundamental questions regarding the emplacement age of the plateau and its temporal-spatial evolution. Geochemical investigations of the recovered rocks will reveal the nature and source of the magmatism. The proposed project will focus on the determination of radiogenic (Sr, Nd, Hf, Pb) isotope compositions to further constrain the magma source composition for comparison with other regional and global LIP magmatism. In particular, we want to address the open question whether the Agulhas Plateau, Northeast Georgia Rise and Maud Rise magmatism can all be attributed to ... Conference Object Antarc* Antarctic Southern Ocean Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic Southern Ocean The Antarctic Indian Maud Rise ENVELOPE(3.000,3.000,-66.000,-66.000) Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) Northeast Georgia Rise ENVELOPE(-32.500,-32.500,-52.500,-52.500) |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
The opening of the Southern Ocean gateways has been debated as a key element in the emergence of the Antarctic Circumpolar Current (ACC), crucial for the onset of global Cenozoic cooling (e.g., Sijp et al., 2014, Glob. Planet. Change 119; Voigt et al., 2013, EPSL 369/370). South of Africa, the opening was associated with the formation of several large igneous provinces (LIPs) including the Mozambique Ridge, Agulhas Plateau and the smaller Northeast Georgia Rise and Maud Rise. Plate tectonic reconstructions imply that the latter two were once part of the much greater Agulhas Plateau and were separated by subsequent rifting (Parsaglia et al., 2008, Geophys. J. Int. 174). It is debated whether and to what extent the emplacement of these large volcanic features obstructed the exchange of water masses between the Atlantic and the Indian Ocean thereby delaying the onset of the ACC. The Agulhas Plateau was drilled during recent IODP Expedition 392 (Uenzelmann-Neben, Bohaty, Childress, et al., IODP Exp. 392 Preliminary Report, 2022, in press). Igneous rocks were recovered at two sites on the southern part of the plateau (Sites U1579, U1580) and at one site near its northern edge (U1582). Preliminary (shipboard) data indicate that all sites returned tholeiitic basalts, formed by low pressure (shallow magma chamber) fractionation of mainly olivine and plagioclase (as typical for mid-ocean ridge basalts and many LIP lavas). 40Ar/39Ar dating will help to answer fundamental questions regarding the emplacement age of the plateau and its temporal-spatial evolution. Geochemical investigations of the recovered rocks will reveal the nature and source of the magmatism. The proposed project will focus on the determination of radiogenic (Sr, Nd, Hf, Pb) isotope compositions to further constrain the magma source composition for comparison with other regional and global LIP magmatism. In particular, we want to address the open question whether the Agulhas Plateau, Northeast Georgia Rise and Maud Rise magmatism can all be attributed to ... |
format |
Conference Object |
author |
Geldmacher, Joerg Davidson, Peter C Liu, Jia Ichiyama, Yuji Hoernle, Kaj Uenzelmann-Neben, Gabriele Bohaty, Steven M Childress, Laurel B |
spellingShingle |
Geldmacher, Joerg Davidson, Peter C Liu, Jia Ichiyama, Yuji Hoernle, Kaj Uenzelmann-Neben, Gabriele Bohaty, Steven M Childress, Laurel B The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
author_facet |
Geldmacher, Joerg Davidson, Peter C Liu, Jia Ichiyama, Yuji Hoernle, Kaj Uenzelmann-Neben, Gabriele Bohaty, Steven M Childress, Laurel B |
author_sort |
Geldmacher, Joerg |
title |
The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
title_short |
The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
title_full |
The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
title_fullStr |
The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
title_full_unstemmed |
The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 |
title_sort |
origin of the agulhas plateau at the african-southern ocean gateway: planned research on igneous rocks from exp. 392 |
publishDate |
2022 |
url |
https://epic.awi.de/id/eprint/57041/ https://hdl.handle.net/10013/epic.4814dfbc-ed94-491e-a318-d371a980f1d3 |
long_lat |
ENVELOPE(3.000,3.000,-66.000,-66.000) ENVELOPE(-32.500,-32.500,-52.500,-52.500) ENVELOPE(-32.500,-32.500,-52.500,-52.500) |
geographic |
Antarctic Southern Ocean The Antarctic Indian Maud Rise Georgia Rise Northeast Georgia Rise |
geographic_facet |
Antarctic Southern Ocean The Antarctic Indian Maud Rise Georgia Rise Northeast Georgia Rise |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
EPIC3DFG ICDP/IOCP Kolloquium, Potsdam, Germany, 2022-11-01-2022-11-03IODP/ICDP Kolloquium 2022, Abstract Volume, (Scientific Technical Report STR; 22/07) |
op_relation |
Geldmacher, J. , Davidson, P. C. , Liu, J. , Ichiyama, Y. , Hoernle, K. , Uenzelmann-Neben, G. orcid:0000-0002-0115-5923 , Bohaty, S. M. and Childress, L. B. , IODP Expedition 392 Science Party (2022) The origin of the Agulhas Plateau at the African-Southern Ocean gateway: Planned research on igneous rocks from Exp. 392 , DFG ICDP/IOCP Kolloquium, Potsdam, Germany, 1 November 2022 - 3 November 2022 . doi:10.48440/gfz.b103-22074 <https://doi.org/10.48440/gfz.b103-22074> , hdl:10013/epic.4814dfbc-ed94-491e-a318-d371a980f1d3 |
op_doi |
https://doi.org/10.48440/gfz.b103-22074 |
_version_ |
1766223289361891328 |