Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean
The global warming trend of the latest Oligocene was interrupted by several cooling events associated with Antarctic glaciations. These cooling events affected surface water productivity and plankton assemblages. Well-preserved radiolarians were obtained from upper Oligocene to lower Miocene sedimen...
Main Authors: | , , , , |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2005
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.685594 https://doi.org/10.1594/PANGAEA.685594 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.685594 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.685594 2023-05-15T13:42:09+02:00 Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean Kamikuri, Shin-Ichi Nishi, Hiroshi Moore, Theodore C Nigrini, Catherine A Motoyama, Isao MEDIAN LATITUDE: 8.344805 * MEDIAN LONGITUDE: -138.691155 * SOUTH-BOUND LATITUDE: 7.800160 * WEST-BOUND LONGITUDE: -142.015650 * NORTH-BOUND LATITUDE: 8.889450 * EAST-BOUND LONGITUDE: -135.366660 * DATE/TIME START: 2001-11-14T00:00:00 * DATE/TIME END: 2001-11-23T00:00:00 2005-03-06 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.685594 https://doi.org/10.1594/PANGAEA.685594 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.685594 https://doi.org/10.1594/PANGAEA.685594 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Kamikuri, Shin-Ichi; Nishi, Hiroshi; Moore, Theodore C; Nigrini, Catherine A; Motoyama, Isao (2005): Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean. Marine Micropaleontology, 57(3-4), 74-96, https://doi.org/10.1016/j.marmicro.2005.07.004 199-1218A 199-1219A DRILL Drilling/drill rig Joides Resolution Leg199 North Pacific Ocean Ocean Drilling Program ODP Dataset 2005 ftpangaea https://doi.org/10.1594/PANGAEA.685594 https://doi.org/10.1016/j.marmicro.2005.07.004 2023-01-20T07:31:08Z The global warming trend of the latest Oligocene was interrupted by several cooling events associated with Antarctic glaciations. These cooling events affected surface water productivity and plankton assemblages. Well-preserved radiolarians were obtained from upper Oligocene to lower Miocene sediments at Ocean Drilling Program (ODP) Leg 199 Sites 1218 and 1219 in the equatorial Pacific, and 110 radiolarian species were identified. Four episodes of significant radiolarian faunal changes were identified: middle late Oligocene (27.5 to 27.3 Ma), latest Oligocene (24.4 Ma), earliest Miocene (23.3 Ma), and middle early Miocene (21.6 Ma). These four episodes approximately coincide with increases and decreases of biogenic silica accumulation rates and increases in delta18O values coded as „Oi“ and „Mi“ events. These data indicate that Antarctic glaciations were associated with change of siliceous sedimentation patterns and faunal changes in the equatorial Pacific. Radiolarian fauna was divided into three assemblages based on variations in radiolarian productivity, species richness and the composition of dominant species: a late Oligocene assemblage (27.6 to 24.4 Ma), a transitional assemblage (24.4 to 23.3 Ma) and an early Miocene assemblage (23.3 to 21.2 Ma). The late Oligocene assemblage is characterized by relatively high productivity, low species richness and four dominant species of Tholospyris anthophora, Stichocorys subligata, Lophocyrtis nomas and Lithelius spp. The transitional assemblage represents relatively low values of productivity and species richness, and consists of three dominant species of T. anthophora, S. subligata and L. nomas. The characteristics of the early Miocene assemblage are relatively low productivity, but high species richness. The two dominant species present in this assemblage are T. anthophora and Cyrtocapsella tetrapera. The most significant faunal turnover of radiolarians is marked at the boundary between the transitional/early Miocene assemblages. Dataset Antarc* Antarctic PANGAEA - Data Publisher for Earth & Environmental Science Antarctic Pacific ENVELOPE(-142.015650,-135.366660,8.889450,7.800160) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
199-1218A 199-1219A DRILL Drilling/drill rig Joides Resolution Leg199 North Pacific Ocean Ocean Drilling Program ODP |
spellingShingle |
199-1218A 199-1219A DRILL Drilling/drill rig Joides Resolution Leg199 North Pacific Ocean Ocean Drilling Program ODP Kamikuri, Shin-Ichi Nishi, Hiroshi Moore, Theodore C Nigrini, Catherine A Motoyama, Isao Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
topic_facet |
199-1218A 199-1219A DRILL Drilling/drill rig Joides Resolution Leg199 North Pacific Ocean Ocean Drilling Program ODP |
description |
The global warming trend of the latest Oligocene was interrupted by several cooling events associated with Antarctic glaciations. These cooling events affected surface water productivity and plankton assemblages. Well-preserved radiolarians were obtained from upper Oligocene to lower Miocene sediments at Ocean Drilling Program (ODP) Leg 199 Sites 1218 and 1219 in the equatorial Pacific, and 110 radiolarian species were identified. Four episodes of significant radiolarian faunal changes were identified: middle late Oligocene (27.5 to 27.3 Ma), latest Oligocene (24.4 Ma), earliest Miocene (23.3 Ma), and middle early Miocene (21.6 Ma). These four episodes approximately coincide with increases and decreases of biogenic silica accumulation rates and increases in delta18O values coded as „Oi“ and „Mi“ events. These data indicate that Antarctic glaciations were associated with change of siliceous sedimentation patterns and faunal changes in the equatorial Pacific. Radiolarian fauna was divided into three assemblages based on variations in radiolarian productivity, species richness and the composition of dominant species: a late Oligocene assemblage (27.6 to 24.4 Ma), a transitional assemblage (24.4 to 23.3 Ma) and an early Miocene assemblage (23.3 to 21.2 Ma). The late Oligocene assemblage is characterized by relatively high productivity, low species richness and four dominant species of Tholospyris anthophora, Stichocorys subligata, Lophocyrtis nomas and Lithelius spp. The transitional assemblage represents relatively low values of productivity and species richness, and consists of three dominant species of T. anthophora, S. subligata and L. nomas. The characteristics of the early Miocene assemblage are relatively low productivity, but high species richness. The two dominant species present in this assemblage are T. anthophora and Cyrtocapsella tetrapera. The most significant faunal turnover of radiolarians is marked at the boundary between the transitional/early Miocene assemblages. |
format |
Dataset |
author |
Kamikuri, Shin-Ichi Nishi, Hiroshi Moore, Theodore C Nigrini, Catherine A Motoyama, Isao |
author_facet |
Kamikuri, Shin-Ichi Nishi, Hiroshi Moore, Theodore C Nigrini, Catherine A Motoyama, Isao |
author_sort |
Kamikuri, Shin-Ichi |
title |
Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
title_short |
Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
title_full |
Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
title_fullStr |
Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
title_full_unstemmed |
Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean |
title_sort |
radiolarian faunal turnover across the oligocene/miocene boundary in the equatorial pacific ocean |
publisher |
PANGAEA |
publishDate |
2005 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.685594 https://doi.org/10.1594/PANGAEA.685594 |
op_coverage |
MEDIAN LATITUDE: 8.344805 * MEDIAN LONGITUDE: -138.691155 * SOUTH-BOUND LATITUDE: 7.800160 * WEST-BOUND LONGITUDE: -142.015650 * NORTH-BOUND LATITUDE: 8.889450 * EAST-BOUND LONGITUDE: -135.366660 * DATE/TIME START: 2001-11-14T00:00:00 * DATE/TIME END: 2001-11-23T00:00:00 |
long_lat |
ENVELOPE(-142.015650,-135.366660,8.889450,7.800160) |
geographic |
Antarctic Pacific |
geographic_facet |
Antarctic Pacific |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Supplement to: Kamikuri, Shin-Ichi; Nishi, Hiroshi; Moore, Theodore C; Nigrini, Catherine A; Motoyama, Isao (2005): Radiolarian faunal turnover across the Oligocene/Miocene boundary in the equatorial Pacific Ocean. Marine Micropaleontology, 57(3-4), 74-96, https://doi.org/10.1016/j.marmicro.2005.07.004 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.685594 https://doi.org/10.1594/PANGAEA.685594 |
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.685594 https://doi.org/10.1016/j.marmicro.2005.07.004 |
_version_ |
1766163304202371072 |