Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau
Carbonate-free portions of Upper Cretaceous to Holocene sediment samples from the Kerguelen Plateau in the southern Indian Ocean were investigated by X-ray diffraction. Downhole variations in the content of opal-A, opal-CT, quartz, feldspar, barite, and clinoptilolite were studied at Site 737 on the...
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1991
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.758100 2024-09-15T17:41:13+00:00 Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau Bohrmann, Gerhard Ehrmann, Werner MEDIAN LATITUDE: -58.172000 * MEDIAN LONGITUDE: 78.805067 * SOUTH-BOUND LATITUDE: -62.709000 * WEST-BOUND LONGITUDE: 73.032400 * NORTH-BOUND LATITUDE: -50.228000 * EAST-BOUND LONGITUDE: 82.787800 * DATE/TIME START: 1987-12-30T04:30:00 * DATE/TIME END: 1988-02-06T19:15:00 1991 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.758100 https://doi.org/10.1594/PANGAEA.758100 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.758100 https://doi.org/10.1594/PANGAEA.758100 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Bohrmann, Gerhard; Ehrmann, Werner (1991): Analysis of Sedimentary Facies Using Bulk Mineralogic Characteristics in Cretaceous to Quaternary Sediments from the Kerguelen Plateau: Sites 737, 738, and 744. In: Barron, J; Larsen, B; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 119, 211-223, https://doi.org/10.2973/odp.proc.sr.119.122.1991 119-737A 119-737B 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.75810010.2973/odp.proc.sr.119.122.1991 2024-07-24T02:31:20Z Carbonate-free portions of Upper Cretaceous to Holocene sediment samples from the Kerguelen Plateau in the southern Indian Ocean were investigated by X-ray diffraction. Downhole variations in the content of opal-A, opal-CT, quartz, feldspar, barite, and clinoptilolite were studied at Site 737 on the northern Kerguelen Plateau and at Sites 744 and 738 on the southern Kerguelen Plateau. The variation of these components reflects temporal changes in the depositional history of the Kerguelen Plateau as well as major differences in the sedimentary evolution between the northern plateau and the southern plateau. Carbonate is the dominant component in the pelagic sediments on the Kerguelen Plateau. In addition, biogenic opal sedimentation plays an important role throughout most of the sequence. A major increase in opal accumulation is documented at all sites in late Miocene time, which is in accordance with the well-known increase in silica productivity probably caused by a major cooling step. Because of its position near the Polar Frontal Zone, sediments from Site 737 show a more extensive opal deposition than at Sites 744 and 738. An earlier productivity pulse is documented at Site 744 on the southern plateau within the early Oligocene, following the initial phase of intense East Antarctic glaciation. This cooling event resulted in higher amounts of ice-rafted terrigenous quartz and, to a lesser extent, feldspar. With the exception of the Site 744 sediments, opal deposition in Paleogene and older sediments can be reconstructed only from the diagenetic transformation products of opal-CT and probably clinoptilolite. In contrast to the southern sequence, on the northern Kerguelen Plateau higher amounts of clinoptilolite and no opal-CT were found. These major differences in the diagenetic environments may be due to extensive volcanism in the northern area. The volcanic influence at Site 737 is well recorded by the higher feldspar content and higher amounts of volcanic glass shards. Other/Unknown Material Antarc* Antarctic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(73.032400,82.787800,-50.228000,-62.709000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
119-737A 119-737B 119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP |
spellingShingle |
119-737A 119-737B 119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP Bohrmann, Gerhard Ehrmann, Werner Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
topic_facet |
119-737A 119-737B 119-738B 119-738C 119-744A DRILL Drilling/drill rig Indian Ocean Joides Resolution Leg119 Ocean Drilling Program ODP |
description |
Carbonate-free portions of Upper Cretaceous to Holocene sediment samples from the Kerguelen Plateau in the southern Indian Ocean were investigated by X-ray diffraction. Downhole variations in the content of opal-A, opal-CT, quartz, feldspar, barite, and clinoptilolite were studied at Site 737 on the northern Kerguelen Plateau and at Sites 744 and 738 on the southern Kerguelen Plateau. The variation of these components reflects temporal changes in the depositional history of the Kerguelen Plateau as well as major differences in the sedimentary evolution between the northern plateau and the southern plateau. Carbonate is the dominant component in the pelagic sediments on the Kerguelen Plateau. In addition, biogenic opal sedimentation plays an important role throughout most of the sequence. A major increase in opal accumulation is documented at all sites in late Miocene time, which is in accordance with the well-known increase in silica productivity probably caused by a major cooling step. Because of its position near the Polar Frontal Zone, sediments from Site 737 show a more extensive opal deposition than at Sites 744 and 738. An earlier productivity pulse is documented at Site 744 on the southern plateau within the early Oligocene, following the initial phase of intense East Antarctic glaciation. This cooling event resulted in higher amounts of ice-rafted terrigenous quartz and, to a lesser extent, feldspar. With the exception of the Site 744 sediments, opal deposition in Paleogene and older sediments can be reconstructed only from the diagenetic transformation products of opal-CT and probably clinoptilolite. In contrast to the southern sequence, on the northern Kerguelen Plateau higher amounts of clinoptilolite and no opal-CT were found. These major differences in the diagenetic environments may be due to extensive volcanism in the northern area. The volcanic influence at Site 737 is well recorded by the higher feldspar content and higher amounts of volcanic glass shards. |
format |
Other/Unknown Material |
author |
Bohrmann, Gerhard Ehrmann, Werner |
author_facet |
Bohrmann, Gerhard Ehrmann, Werner |
author_sort |
Bohrmann, Gerhard |
title |
Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
title_short |
Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
title_full |
Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
title_fullStr |
Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
title_full_unstemmed |
Bulk mineralogy of Cretaceous to Quaternary sediments from the Kerguelen Plateau |
title_sort |
bulk mineralogy of cretaceous to quaternary sediments from the kerguelen plateau |
publisher |
PANGAEA |
publishDate |
1991 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.758100 https://doi.org/10.1594/PANGAEA.758100 |
op_coverage |
MEDIAN LATITUDE: -58.172000 * MEDIAN LONGITUDE: 78.805067 * SOUTH-BOUND LATITUDE: -62.709000 * WEST-BOUND LONGITUDE: 73.032400 * NORTH-BOUND LATITUDE: -50.228000 * EAST-BOUND LONGITUDE: 82.787800 * DATE/TIME START: 1987-12-30T04:30:00 * DATE/TIME END: 1988-02-06T19:15:00 |
long_lat |
ENVELOPE(73.032400,82.787800,-50.228000,-62.709000) |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Supplement to: Bohrmann, Gerhard; Ehrmann, Werner (1991): Analysis of Sedimentary Facies Using Bulk Mineralogic Characteristics in Cretaceous to Quaternary Sediments from the Kerguelen Plateau: Sites 737, 738, and 744. In: Barron, J; Larsen, B; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 119, 211-223, https://doi.org/10.2973/odp.proc.sr.119.122.1991 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.758100 https://doi.org/10.1594/PANGAEA.758100 |
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.75810010.2973/odp.proc.sr.119.122.1991 |
_version_ |
1810487357557702656 |