Isotope geochemistry of Ninetyeast Ridge basalts
The Ninetyeast Ridge lavas have Sr and Nd isotopic ratios intermediate between those of Indian Ocean MORBs and those of the very enriched Kerguelen hot spot. In an Nd-Sr isotope diagram, they also plot close to the fields of St. Paul Island lavas and of the early magmatism on Kerguelen Archipelago....
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.759538 2023-05-15T13:42:10+02:00 Isotope geochemistry of Ninetyeast Ridge basalts Weis, Dominique A M Frey, Frederick A MEDIAN LATITUDE: -10.010273 * MEDIAN LONGITUDE: 89.003760 * SOUTH-BOUND LATITUDE: -27.355000 * WEST-BOUND LONGITUDE: 87.597400 * NORTH-BOUND LATITUDE: 5.384200 * EAST-BOUND LONGITUDE: 90.361200 * DATE/TIME START: 1988-05-26T00:00:00 * DATE/TIME END: 1988-06-24T13:30:00 1991-04-15 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.759538 https://doi.org/10.1594/PANGAEA.759538 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.759538 https://doi.org/10.1594/PANGAEA.759538 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Weis, Dominique A M; Frey, Frederick A (1991): Isotope geochemistry of Ninetyeast Ridge basement basalts: Sr, Nd, and Pb evidence for involvement of the Kerguelen Hot Spot. In: Weissel, J; Peirce, J; Taylor, E; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 121, 591-610, https://doi.org/10.2973/odp.proc.sr.121.170.1991 121-756C 121-756D 121-757C 121-758A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg121 Ocean Drilling Program ODP South Indian Ridge South Indian Ocean Dataset 1991 ftpangaea https://doi.org/10.1594/PANGAEA.759538 https://doi.org/10.2973/odp.proc.sr.121.170.1991 2023-01-20T07:32:07Z The Ninetyeast Ridge lavas have Sr and Nd isotopic ratios intermediate between those of Indian Ocean MORBs and those of the very enriched Kerguelen hot spot. In an Nd-Sr isotope diagram, they also plot close to the fields of St. Paul Island lavas and of the early magmatism on Kerguelen Archipelago. The Ninetyeast Ridge lavas were generated by mixing among at least three components: a depleted, MORB-type component, such as the one erupted today on the Southeast Indian Ridge; a very enriched, high- Sr/ Sr, low-epsilon-Nd, OIB-type component (the Kerguelen hot spot); and an OIB-type component comparable to that sampled from the St. Paul (and Amsterdam) lavas. The Ninetyeast Ridge lavas show a typical Dupal anomaly signature and Pb, Sr, and Nd isotopic systematics indicate that the Kerguelen hot spot was involved in the ridge's formation as the Indian plate moved northward. The different sites cored during ODP Leg 121 show a trend in their isotopic compositions, from less radiogenic Pb/ Pb ratios and intermediate 87Sr/86Sr and 143Nd/**Nd ratios in the oldest lavas (Site 758) toward more radiogenic 206Pb/204Pb, higher epsilon-Nd, and lower 87Sr/86Sr values in the youngest lavas (Site 756). The lavas from Site 757 have 206Pb/204Pb ratios intermediate between those of the lavas from Sites 756 and 758 and higher 87Sr/86Sr and lower epsilon-Nd values. The relative proportions of the hot spot(s) and MORB component have evolved with time, reflecting differences of tectonic setting: the relative proportion of the Kerguelen hot spot component appears lower in the younger Site 756 lavas than in the older lavas from Sites 757 and 758. Site 756 coincides with the beginning of rifting at the Southeast Indian Ridge, about 43 Ma ago. The formation of the early Kerguelen Archipelago lavas may have drained most of the plume-derived material toward the Antarctic plate. Alternatively, the proximity of the spreading-ridge axis may account for the isotopic similarity of the Site 756 lavas to young lavas erupted on the Southeast Indian ... Dataset Antarc* Antarctic PANGAEA - Data Publisher for Earth & Environmental Science Antarctic Indian Kerguelen Southeast Indian Ridge ENVELOPE(110.000,110.000,-50.000,-50.000) The Antarctic ENVELOPE(87.597400,90.361200,5.384200,-27.355000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
121-756C 121-756D 121-757C 121-758A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg121 Ocean Drilling Program ODP South Indian Ridge South Indian Ocean |
spellingShingle |
121-756C 121-756D 121-757C 121-758A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg121 Ocean Drilling Program ODP South Indian Ridge South Indian Ocean Weis, Dominique A M Frey, Frederick A Isotope geochemistry of Ninetyeast Ridge basalts |
topic_facet |
121-756C 121-756D 121-757C 121-758A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg121 Ocean Drilling Program ODP South Indian Ridge South Indian Ocean |
description |
The Ninetyeast Ridge lavas have Sr and Nd isotopic ratios intermediate between those of Indian Ocean MORBs and those of the very enriched Kerguelen hot spot. In an Nd-Sr isotope diagram, they also plot close to the fields of St. Paul Island lavas and of the early magmatism on Kerguelen Archipelago. The Ninetyeast Ridge lavas were generated by mixing among at least three components: a depleted, MORB-type component, such as the one erupted today on the Southeast Indian Ridge; a very enriched, high- Sr/ Sr, low-epsilon-Nd, OIB-type component (the Kerguelen hot spot); and an OIB-type component comparable to that sampled from the St. Paul (and Amsterdam) lavas. The Ninetyeast Ridge lavas show a typical Dupal anomaly signature and Pb, Sr, and Nd isotopic systematics indicate that the Kerguelen hot spot was involved in the ridge's formation as the Indian plate moved northward. The different sites cored during ODP Leg 121 show a trend in their isotopic compositions, from less radiogenic Pb/ Pb ratios and intermediate 87Sr/86Sr and 143Nd/**Nd ratios in the oldest lavas (Site 758) toward more radiogenic 206Pb/204Pb, higher epsilon-Nd, and lower 87Sr/86Sr values in the youngest lavas (Site 756). The lavas from Site 757 have 206Pb/204Pb ratios intermediate between those of the lavas from Sites 756 and 758 and higher 87Sr/86Sr and lower epsilon-Nd values. The relative proportions of the hot spot(s) and MORB component have evolved with time, reflecting differences of tectonic setting: the relative proportion of the Kerguelen hot spot component appears lower in the younger Site 756 lavas than in the older lavas from Sites 757 and 758. Site 756 coincides with the beginning of rifting at the Southeast Indian Ridge, about 43 Ma ago. The formation of the early Kerguelen Archipelago lavas may have drained most of the plume-derived material toward the Antarctic plate. Alternatively, the proximity of the spreading-ridge axis may account for the isotopic similarity of the Site 756 lavas to young lavas erupted on the Southeast Indian ... |
format |
Dataset |
author |
Weis, Dominique A M Frey, Frederick A |
author_facet |
Weis, Dominique A M Frey, Frederick A |
author_sort |
Weis, Dominique A M |
title |
Isotope geochemistry of Ninetyeast Ridge basalts |
title_short |
Isotope geochemistry of Ninetyeast Ridge basalts |
title_full |
Isotope geochemistry of Ninetyeast Ridge basalts |
title_fullStr |
Isotope geochemistry of Ninetyeast Ridge basalts |
title_full_unstemmed |
Isotope geochemistry of Ninetyeast Ridge basalts |
title_sort |
isotope geochemistry of ninetyeast ridge basalts |
publisher |
PANGAEA |
publishDate |
1991 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.759538 https://doi.org/10.1594/PANGAEA.759538 |
op_coverage |
MEDIAN LATITUDE: -10.010273 * MEDIAN LONGITUDE: 89.003760 * SOUTH-BOUND LATITUDE: -27.355000 * WEST-BOUND LONGITUDE: 87.597400 * NORTH-BOUND LATITUDE: 5.384200 * EAST-BOUND LONGITUDE: 90.361200 * DATE/TIME START: 1988-05-26T00:00:00 * DATE/TIME END: 1988-06-24T13:30:00 |
long_lat |
ENVELOPE(110.000,110.000,-50.000,-50.000) ENVELOPE(87.597400,90.361200,5.384200,-27.355000) |
geographic |
Antarctic Indian Kerguelen Southeast Indian Ridge The Antarctic |
geographic_facet |
Antarctic Indian Kerguelen Southeast Indian Ridge The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Supplement to: Weis, Dominique A M; Frey, Frederick A (1991): Isotope geochemistry of Ninetyeast Ridge basement basalts: Sr, Nd, and Pb evidence for involvement of the Kerguelen Hot Spot. In: Weissel, J; Peirce, J; Taylor, E; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 121, 591-610, https://doi.org/10.2973/odp.proc.sr.121.170.1991 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.759538 https://doi.org/10.1594/PANGAEA.759538 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.759538 https://doi.org/10.2973/odp.proc.sr.121.170.1991 |
_version_ |
1766164035729883136 |