Sedimentology of ODP Leg 119 samples
Cretaceous to Quaternary sediments recovered at Leg 119 Sites 738 and 744 on the southern tip of the Kerguelen Plateau were studied in order to determine the depositional environment and the paleoceanography of the southern Indian Ocean and especially the long-term glacial history of East Antarctica...
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1991
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.758063 2024-09-15T17:40:52+00:00 Sedimentology of ODP Leg 119 samples Ehrmann, Werner MEDIAN LATITUDE: -62.313500 * MEDIAN LONGITUDE: 82.020320 * SOUTH-BOUND LATITUDE: -62.709000 * WEST-BOUND LONGITUDE: 80.595000 * NORTH-BOUND LATITUDE: -61.579000 * EAST-BOUND LONGITUDE: 82.787800 * DATE/TIME START: 1988-01-10T16:30:00 * DATE/TIME END: 1988-02-06T19:15:00 1991 application/zip, 4 datasets https://doi.pangaea.de/10.1594/PANGAEA.758063 https://doi.org/10.1594/PANGAEA.758063 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.758063 https://doi.org/10.1594/PANGAEA.758063 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Ehrmann, Werner (1991): Implications of sediment composition on the southern Kerguelen Plateau for paleoclimate and depositional environment. In: Barron, J; Larsen, B; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 119, 185-210, https://doi.org/10.2973/odp.proc.sr.119.121.1991 119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP dataset publication series 1991 ftpangaea https://doi.org/10.1594/PANGAEA.75806310.2973/odp.proc.sr.119.121.1991 2024-07-24T02:31:20Z Cretaceous to Quaternary sediments recovered at Leg 119 Sites 738 and 744 on the southern tip of the Kerguelen Plateau were studied in order to determine the depositional environment and the paleoceanography of the southern Indian Ocean and especially the long-term glacial history of East Antarctica. Emphasis is given to bulk-sediment composition, grain-size data, and clay mineralogy. The sediment sequence at the two sites is generally of a highly pelagic character, with nannofossil oozes, chalks, and limestones dominant from the Turanian to upper Miocene and diatom oozes dominant within the uppermost Miocene to Holocene interval. The first indication of glaciation at sea level is the occurrence of isolated gravel and terrigenous sand grains, which indicate ice rafting in the middle Eocene interval of 45.0-42.3 Ma. A major intensification of glaciation, probably the onset of continental East Antarctic glaciation, is recorded in sediments of early Oligocene age (36.0 Ma). All major sediment parameters document this event. The clay mineralogy changes from smectite-dominated assemblages, typical of moderately warm and humid climatic conditions in which chemical weathering processes are prevalent, to illite- and chlorite-dominated assemblages, indicative of cooler climates and physical weathering. Ice-rafted debris of both gravel and sand size occurs in large quantities in that interval and coincides with a change in the mode of carbonate deposition. Carbonate contents are relatively high and uniform (90%-95%) in strata younger than early Oligocene; in Oligocene to upper Miocene strata they fluctuate between 65% and 95%. Oligocene and Neogene hiatuses reflect an intensification of oceanic circulation and the increased erosional force of Circumpolar Deep Water. The long-term Cenozoic cooling trend was interrupted by a phase of early Miocene warming indicated by maximum Neogene smectite concentrations. Although ice-rafted debris is present only in minor amounts and mainly in the silt fraction of early Oligocene to ... Other/Unknown Material Antarc* Antarctic Antarctica East Antarctica PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(80.595000,82.787800,-61.579000,-62.709000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP |
spellingShingle |
119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP Ehrmann, Werner Sedimentology of ODP Leg 119 samples |
topic_facet |
119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP |
description |
Cretaceous to Quaternary sediments recovered at Leg 119 Sites 738 and 744 on the southern tip of the Kerguelen Plateau were studied in order to determine the depositional environment and the paleoceanography of the southern Indian Ocean and especially the long-term glacial history of East Antarctica. Emphasis is given to bulk-sediment composition, grain-size data, and clay mineralogy. The sediment sequence at the two sites is generally of a highly pelagic character, with nannofossil oozes, chalks, and limestones dominant from the Turanian to upper Miocene and diatom oozes dominant within the uppermost Miocene to Holocene interval. The first indication of glaciation at sea level is the occurrence of isolated gravel and terrigenous sand grains, which indicate ice rafting in the middle Eocene interval of 45.0-42.3 Ma. A major intensification of glaciation, probably the onset of continental East Antarctic glaciation, is recorded in sediments of early Oligocene age (36.0 Ma). All major sediment parameters document this event. The clay mineralogy changes from smectite-dominated assemblages, typical of moderately warm and humid climatic conditions in which chemical weathering processes are prevalent, to illite- and chlorite-dominated assemblages, indicative of cooler climates and physical weathering. Ice-rafted debris of both gravel and sand size occurs in large quantities in that interval and coincides with a change in the mode of carbonate deposition. Carbonate contents are relatively high and uniform (90%-95%) in strata younger than early Oligocene; in Oligocene to upper Miocene strata they fluctuate between 65% and 95%. Oligocene and Neogene hiatuses reflect an intensification of oceanic circulation and the increased erosional force of Circumpolar Deep Water. The long-term Cenozoic cooling trend was interrupted by a phase of early Miocene warming indicated by maximum Neogene smectite concentrations. Although ice-rafted debris is present only in minor amounts and mainly in the silt fraction of early Oligocene to ... |
format |
Other/Unknown Material |
author |
Ehrmann, Werner |
author_facet |
Ehrmann, Werner |
author_sort |
Ehrmann, Werner |
title |
Sedimentology of ODP Leg 119 samples |
title_short |
Sedimentology of ODP Leg 119 samples |
title_full |
Sedimentology of ODP Leg 119 samples |
title_fullStr |
Sedimentology of ODP Leg 119 samples |
title_full_unstemmed |
Sedimentology of ODP Leg 119 samples |
title_sort |
sedimentology of odp leg 119 samples |
publisher |
PANGAEA |
publishDate |
1991 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.758063 https://doi.org/10.1594/PANGAEA.758063 |
op_coverage |
MEDIAN LATITUDE: -62.313500 * MEDIAN LONGITUDE: 82.020320 * SOUTH-BOUND LATITUDE: -62.709000 * WEST-BOUND LONGITUDE: 80.595000 * NORTH-BOUND LATITUDE: -61.579000 * EAST-BOUND LONGITUDE: 82.787800 * DATE/TIME START: 1988-01-10T16:30:00 * DATE/TIME END: 1988-02-06T19:15:00 |
long_lat |
ENVELOPE(80.595000,82.787800,-61.579000,-62.709000) |
genre |
Antarc* Antarctic Antarctica East Antarctica |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica |
op_source |
Supplement to: Ehrmann, Werner (1991): Implications of sediment composition on the southern Kerguelen Plateau for paleoclimate and depositional environment. In: Barron, J; Larsen, B; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 119, 185-210, https://doi.org/10.2973/odp.proc.sr.119.121.1991 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.758063 https://doi.org/10.1594/PANGAEA.758063 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1594/PANGAEA.75806310.2973/odp.proc.sr.119.121.1991 |
_version_ |
1810486941495328768 |