Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B
Middle Eocene to Late Oligocene sediments from near the crest (Site 689B, water depth 2080 m) and flank (water depth 2914 m) of the Maud Rise (62°S) have been investigated by coarse fraction analysis and have revealed the following: (1) The middle Eocene (50-40 Ma) was a period of pure carbonate sed...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.759819 2024-09-15T17:42:32+00:00 Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B Diester-Haass, Lieselotte MEDIAN LATITUDE: -64.839000 * MEDIAN LONGITUDE: 2.152400 * SOUTH-BOUND LATITUDE: -65.161000 * WEST-BOUND LONGITUDE: 1.204900 * NORTH-BOUND LATITUDE: -64.517000 * EAST-BOUND LONGITUDE: 3.099900 * DATE/TIME START: 1987-01-16T08:00:00 * DATE/TIME END: 1987-01-21T07:00:00 1991 application/zip, 8 datasets https://doi.pangaea.de/10.1594/PANGAEA.759819 https://doi.org/10.1594/PANGAEA.759819 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.759819 https://doi.org/10.1594/PANGAEA.759819 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Diester-Haass, Lieselotte (1991): Eocene/Oligocene paleoceanography in the Antarctic Ocean, Atlantic sector (Maud Rise, ODP Leg 113, Site 689B and 690B). Marine Geology, 100(1-4), 249-276, https://doi.org/10.1016/0025-3227(91)90235-V 113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean dataset publication series 1991 ftpangaea https://doi.org/10.1594/PANGAEA.75981910.1016/0025-3227(91)90235-V 2024-07-24T02:31:20Z Middle Eocene to Late Oligocene sediments from near the crest (Site 689B, water depth 2080 m) and flank (water depth 2914 m) of the Maud Rise (62°S) have been investigated by coarse fraction analysis and have revealed the following: (1) The middle Eocene (50-40 Ma) was a period of pure carbonate sedimentation, with good preservation of carbonate microfossils. No opal > 40 µm is present. (2) In the late Eocene (40-36.5 Ma) opal fossils (mainly radiolaria, and some diatoms > 40 µm) appeared for the first time. Three maxima in opal sedimentation (Eocene/Oligocene boundary, middle early Oligocene and early/late Oligocene boundary) are separated by increases in carbonate sedimentation. The dissolution of carbonate fossils is strong in the opal-rich layers. Opal sedimentation is attributed to cooling and probably more vigorous atmospheric circulation and increased upwelling. (3) Carbonate dissolution increased with water depth in the Oligocene, whereas in the middle Eocene excellent carbonate preservation in the deeper Site 690B and stronger dissolution in the shallower Site 689B is attributed to different bottom-water characteristics. The middle Eocene bottom water probably was formed by strong evaporation at low latitudes, whereas by the earliest Oligocene formation of Antarctic Bottom Water (AABW) had set in. (4) Current influence, not on top but on the flank of the Maud Rise, could be recorded by means of larger grain sizes of benthonic and planktonic microfossils. (5) Ice-rafted debris was not found. Quartz and other minerals are very rare and not larger than 125 µm and may have been supplied by ice as well as by wind or by deep currents. Mica contents were up to 10 times higher in the middle Eocene on the flank compared to on the crest of the Maud Rise, indicating deep current supply. Other/Unknown Material Antarc* Antarctic South Atlantic Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(1.204900,3.099900,-64.517000,-65.161000) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean |
spellingShingle |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean Diester-Haass, Lieselotte Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
topic_facet |
113-689B 113-690B DRILL Drilling/drill rig Joides Resolution Leg113 Ocean Drilling Program ODP South Atlantic Ocean |
description |
Middle Eocene to Late Oligocene sediments from near the crest (Site 689B, water depth 2080 m) and flank (water depth 2914 m) of the Maud Rise (62°S) have been investigated by coarse fraction analysis and have revealed the following: (1) The middle Eocene (50-40 Ma) was a period of pure carbonate sedimentation, with good preservation of carbonate microfossils. No opal > 40 µm is present. (2) In the late Eocene (40-36.5 Ma) opal fossils (mainly radiolaria, and some diatoms > 40 µm) appeared for the first time. Three maxima in opal sedimentation (Eocene/Oligocene boundary, middle early Oligocene and early/late Oligocene boundary) are separated by increases in carbonate sedimentation. The dissolution of carbonate fossils is strong in the opal-rich layers. Opal sedimentation is attributed to cooling and probably more vigorous atmospheric circulation and increased upwelling. (3) Carbonate dissolution increased with water depth in the Oligocene, whereas in the middle Eocene excellent carbonate preservation in the deeper Site 690B and stronger dissolution in the shallower Site 689B is attributed to different bottom-water characteristics. The middle Eocene bottom water probably was formed by strong evaporation at low latitudes, whereas by the earliest Oligocene formation of Antarctic Bottom Water (AABW) had set in. (4) Current influence, not on top but on the flank of the Maud Rise, could be recorded by means of larger grain sizes of benthonic and planktonic microfossils. (5) Ice-rafted debris was not found. Quartz and other minerals are very rare and not larger than 125 µm and may have been supplied by ice as well as by wind or by deep currents. Mica contents were up to 10 times higher in the middle Eocene on the flank compared to on the crest of the Maud Rise, indicating deep current supply. |
format |
Other/Unknown Material |
author |
Diester-Haass, Lieselotte |
author_facet |
Diester-Haass, Lieselotte |
author_sort |
Diester-Haass, Lieselotte |
title |
Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
title_short |
Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
title_full |
Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
title_fullStr |
Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
title_full_unstemmed |
Eocene/Oligocene paleoceanography from ODP Hole 113-689B and Hole 113-690B |
title_sort |
eocene/oligocene paleoceanography from odp hole 113-689b and hole 113-690b |
publisher |
PANGAEA |
publishDate |
1991 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.759819 https://doi.org/10.1594/PANGAEA.759819 |
op_coverage |
MEDIAN LATITUDE: -64.839000 * MEDIAN LONGITUDE: 2.152400 * SOUTH-BOUND LATITUDE: -65.161000 * WEST-BOUND LONGITUDE: 1.204900 * NORTH-BOUND LATITUDE: -64.517000 * EAST-BOUND LONGITUDE: 3.099900 * DATE/TIME START: 1987-01-16T08:00:00 * DATE/TIME END: 1987-01-21T07:00:00 |
long_lat |
ENVELOPE(1.204900,3.099900,-64.517000,-65.161000) |
genre |
Antarc* Antarctic South Atlantic Ocean |
genre_facet |
Antarc* Antarctic South Atlantic Ocean |
op_source |
Supplement to: Diester-Haass, Lieselotte (1991): Eocene/Oligocene paleoceanography in the Antarctic Ocean, Atlantic sector (Maud Rise, ODP Leg 113, Site 689B and 690B). Marine Geology, 100(1-4), 249-276, https://doi.org/10.1016/0025-3227(91)90235-V |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.759819 https://doi.org/10.1594/PANGAEA.759819 |
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.75981910.1016/0025-3227(91)90235-V |
_version_ |
1810489146288898048 |