Diatom abundance index and biogenic opal content for ODP Leg 175 holes
Several sites of Ocean Drilling Program Leg 175 between 20° and 30°S (1081, 1082, 1083, 1084 and 1085) in the Benguela Current system show a distinct opal (and diatom) maximum within the late Pliocene and early Quaternary, spanning the lower half of the Matuyama reversed polarity Chron (MDM, Matuyam...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.735178 2024-09-15T17:44:18+00:00 Diatom abundance index and biogenic opal content for ODP Leg 175 holes Lange, Carina Beatriz Berger, Wolfgang H Lin, Hui-Ling Wefer, Gerold Shipboard Scientific Party MEDIAN LATITUDE: -23.668420 * MEDIAN LONGITUDE: 12.400565 * SOUTH-BOUND LATITUDE: -29.374410 * WEST-BOUND LONGITUDE: 11.217860 * NORTH-BOUND LATITUDE: -19.619690 * EAST-BOUND LONGITUDE: 13.990110 * DATE/TIME START: 1997-09-09T02:00:00 * DATE/TIME END: 1997-09-29T18:15:00 1999 application/zip, 6 datasets https://doi.pangaea.de/10.1594/PANGAEA.735178 https://doi.org/10.1594/PANGAEA.735178 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.735178 https://doi.org/10.1594/PANGAEA.735178 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Lange, Carina Beatriz; Berger, Wolfgang H; Lin, Hui-Ling; Wefer, Gerold; Shipboard Scientific Party (1999): The early Matuyama diatom maximum off SW Africa, Benguela Current System (ODP Leg 175). Marine Geology, 161(2-4), 93-114, https://doi.org/10.1016/S0025-3227(99)00081-X 175-1081A 175-1082A 175-1083A 175-1084A 175-1085A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP dataset publication series 1999 ftpangaea https://doi.org/10.1594/PANGAEA.73517810.1016/S0025-3227(99)00081-X 2024-07-24T02:31:20Z Several sites of Ocean Drilling Program Leg 175 between 20° and 30°S (1081, 1082, 1083, 1084 and 1085) in the Benguela Current system show a distinct opal (and diatom) maximum within the late Pliocene and early Quaternary, spanning the lower half of the Matuyama reversed polarity Chron (MDM, Matuyama Diatom Maximum). This maximum is centered around 2.0-2.6 Ma, and follows a rapid increase of diatom deposition near 3.1 Ma. Within the MDM, we recognized intervals dominated by the antarctic/subantarctic species Thalassiothrix antarctica which have the aspect of diatom mats. The MDM (and the mats) developed during a time of sustained Southern Ocean influence (3.2-1.6 Ma), probably reflecting a period of seasonally-pulsed continuous advection of subantarctic waters into the Benguela Oceanic Current. The onset and cessation of the MDM raises questions about modes in the operation of the silica cycle and the relation of these to major oceanographic events. A depositional model for the late Pliocene is proposed which involves positional changes in a longshore system of fronts, substantial equatorward excursions of subantarctic waters during MDM time, and subsurface waters greatly enriched in silicate. Other/Unknown Material Antarc* Antarctic Antarctica South Atlantic Ocean Southern Ocean PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(11.217860,13.990110,-19.619690,-29.374410) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
175-1081A 175-1082A 175-1083A 175-1084A 175-1085A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP |
spellingShingle |
175-1081A 175-1082A 175-1083A 175-1084A 175-1085A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP Lange, Carina Beatriz Berger, Wolfgang H Lin, Hui-Ling Wefer, Gerold Shipboard Scientific Party Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
topic_facet |
175-1081A 175-1082A 175-1083A 175-1084A 175-1085A Benguela Current South Atlantic Ocean DRILL Drilling/drill rig Joides Resolution Leg175 Ocean Drilling Program ODP |
description |
Several sites of Ocean Drilling Program Leg 175 between 20° and 30°S (1081, 1082, 1083, 1084 and 1085) in the Benguela Current system show a distinct opal (and diatom) maximum within the late Pliocene and early Quaternary, spanning the lower half of the Matuyama reversed polarity Chron (MDM, Matuyama Diatom Maximum). This maximum is centered around 2.0-2.6 Ma, and follows a rapid increase of diatom deposition near 3.1 Ma. Within the MDM, we recognized intervals dominated by the antarctic/subantarctic species Thalassiothrix antarctica which have the aspect of diatom mats. The MDM (and the mats) developed during a time of sustained Southern Ocean influence (3.2-1.6 Ma), probably reflecting a period of seasonally-pulsed continuous advection of subantarctic waters into the Benguela Oceanic Current. The onset and cessation of the MDM raises questions about modes in the operation of the silica cycle and the relation of these to major oceanographic events. A depositional model for the late Pliocene is proposed which involves positional changes in a longshore system of fronts, substantial equatorward excursions of subantarctic waters during MDM time, and subsurface waters greatly enriched in silicate. |
format |
Other/Unknown Material |
author |
Lange, Carina Beatriz Berger, Wolfgang H Lin, Hui-Ling Wefer, Gerold Shipboard Scientific Party |
author_facet |
Lange, Carina Beatriz Berger, Wolfgang H Lin, Hui-Ling Wefer, Gerold Shipboard Scientific Party |
author_sort |
Lange, Carina Beatriz |
title |
Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
title_short |
Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
title_full |
Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
title_fullStr |
Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
title_full_unstemmed |
Diatom abundance index and biogenic opal content for ODP Leg 175 holes |
title_sort |
diatom abundance index and biogenic opal content for odp leg 175 holes |
publisher |
PANGAEA |
publishDate |
1999 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.735178 https://doi.org/10.1594/PANGAEA.735178 |
op_coverage |
MEDIAN LATITUDE: -23.668420 * MEDIAN LONGITUDE: 12.400565 * SOUTH-BOUND LATITUDE: -29.374410 * WEST-BOUND LONGITUDE: 11.217860 * NORTH-BOUND LATITUDE: -19.619690 * EAST-BOUND LONGITUDE: 13.990110 * DATE/TIME START: 1997-09-09T02:00:00 * DATE/TIME END: 1997-09-29T18:15:00 |
long_lat |
ENVELOPE(11.217860,13.990110,-19.619690,-29.374410) |
genre |
Antarc* Antarctic Antarctica South Atlantic Ocean Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctica South Atlantic Ocean Southern Ocean |
op_source |
Supplement to: Lange, Carina Beatriz; Berger, Wolfgang H; Lin, Hui-Ling; Wefer, Gerold; Shipboard Scientific Party (1999): The early Matuyama diatom maximum off SW Africa, Benguela Current System (ODP Leg 175). Marine Geology, 161(2-4), 93-114, https://doi.org/10.1016/S0025-3227(99)00081-X |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.735178 https://doi.org/10.1594/PANGAEA.735178 |
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.73517810.1016/S0025-3227(99)00081-X |
_version_ |
1810491743864356864 |