Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987
Cores recovered at Sites 986 and 987 comprise glacial fan sedimentation associated with the Svalbard-Barents Sea and Greenland Ice Sheets, respectively. At Site 986, the top 150 m and the basal 250 m yielded interpretable magnetic stratigraphies. The record from the intervening 550 m is compromised...
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ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.805085 2024-09-15T17:58:02+00:00 Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 Channell, James E T Smelror, Morten Jansen, Eystein Higgins, Sean M Lehman, Benoît Eidvin, Tor Solheim, Anders MEDIAN LATITUDE: 75.058955 * MEDIAN LONGITUDE: -12.030688 * SOUTH-BOUND LATITUDE: 70.496400 * WEST-BOUND LONGITUDE: -17.937500 * NORTH-BOUND LATITUDE: 77.340600 * EAST-BOUND LONGITUDE: -9.077500 * DATE/TIME START: 1995-08-11T14:25:00 * DATE/TIME END: 1995-09-01T12:15:00 1999 application/zip, 3 datasets https://doi.pangaea.de/10.1594/PANGAEA.805085 https://doi.org/10.1594/PANGAEA.805085 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.805085 https://doi.org/10.1594/PANGAEA.805085 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess Supplement to: Channell, James E T; Smelror, Morten; Jansen, Eystein; Higgins, Sean M; Lehman, Benoît; Eidvin, Tor; Solheim, Anders (1999): Age models for glacial fan deposits off East Greenland and Svalbard (Sites 986 and 987). In: Raymo, ME; Jansen, E; Blum, P; Herbert, TD (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 162, 1-18, https://doi.org/10.2973/odp.proc.sr.162.008.1999 Ocean Drilling Program ODP dataset publication series 1999 ftpangaea https://doi.org/10.1594/PANGAEA.80508510.2973/odp.proc.sr.162.008.1999 2024-07-24T02:31:21Z Cores recovered at Sites 986 and 987 comprise glacial fan sedimentation associated with the Svalbard-Barents Sea and Greenland Ice Sheets, respectively. At Site 986, the top 150 m and the basal 250 m yielded interpretable magnetic stratigraphies. The record from the intervening 550 m is compromised by drilling-related core deformation, poor recovery, and numerous debris flows. The uppermost 150 m appears to record the Brunhes/Matuyama boundary and the Jaramillo Subchron. The base of the drilled section (at ~950 meters below seafloor [mbsf]) is interpreted to lie within the Matuyama Chron (age <2.58 Ma) with an apparent normal polarity interval in the ~730-750 mbsf interval. Dinoflagellate cyst biostratigraphy and Sr isotopic ratios are consistent with a Matuyama age for the base of the drilled section and with the normal polarity interval as the Olduvai Subchron. On the other hand, the last occurrence of Neogloboquadrina atlantica (sinistral) and the last common occurrence of the warm-dwelling Globigerina bulloides at 647-650 mbsf in Hole 986D indicate an age for this level of ~2.3 Ma, inconsistent with the designation of the Olduvai Subchron in the ~730-750 mbsf interval. If the age at 647-650 mbsf in Hole 986D is taken as 2.3 Ma and the base of the hole lies within the Matuyama Chron, then the sedimentation rate in the basal 300 m of the cored section averages 1 m/k.y. At Site 987, the magnetic stratigraphy is fairly unambiguous throughout the section and yields an age of 7.5 Ma (Chron 4n) for the base of the drilled section. The paucity of calcareous and siliceous microfossils precludes biostratigraphic corroboration of the magnetostratigraphic interpretation, although dinoflagellate cysts provide general support, particularly at the base of the section. The age model indicates relatively low sedimentation rates (~5 cm/k.y.) at the base of the section with rates at least four to five times greater during intervals of debris flows at ~5-4.6 and ~2.6 Ma. Other/Unknown Material Barents Sea Greenland Svalbard PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-17.937500,-9.077500,77.340600,70.496400) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
Ocean Drilling Program ODP |
spellingShingle |
Ocean Drilling Program ODP Channell, James E T Smelror, Morten Jansen, Eystein Higgins, Sean M Lehman, Benoît Eidvin, Tor Solheim, Anders Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
topic_facet |
Ocean Drilling Program ODP |
description |
Cores recovered at Sites 986 and 987 comprise glacial fan sedimentation associated with the Svalbard-Barents Sea and Greenland Ice Sheets, respectively. At Site 986, the top 150 m and the basal 250 m yielded interpretable magnetic stratigraphies. The record from the intervening 550 m is compromised by drilling-related core deformation, poor recovery, and numerous debris flows. The uppermost 150 m appears to record the Brunhes/Matuyama boundary and the Jaramillo Subchron. The base of the drilled section (at ~950 meters below seafloor [mbsf]) is interpreted to lie within the Matuyama Chron (age <2.58 Ma) with an apparent normal polarity interval in the ~730-750 mbsf interval. Dinoflagellate cyst biostratigraphy and Sr isotopic ratios are consistent with a Matuyama age for the base of the drilled section and with the normal polarity interval as the Olduvai Subchron. On the other hand, the last occurrence of Neogloboquadrina atlantica (sinistral) and the last common occurrence of the warm-dwelling Globigerina bulloides at 647-650 mbsf in Hole 986D indicate an age for this level of ~2.3 Ma, inconsistent with the designation of the Olduvai Subchron in the ~730-750 mbsf interval. If the age at 647-650 mbsf in Hole 986D is taken as 2.3 Ma and the base of the hole lies within the Matuyama Chron, then the sedimentation rate in the basal 300 m of the cored section averages 1 m/k.y. At Site 987, the magnetic stratigraphy is fairly unambiguous throughout the section and yields an age of 7.5 Ma (Chron 4n) for the base of the drilled section. The paucity of calcareous and siliceous microfossils precludes biostratigraphic corroboration of the magnetostratigraphic interpretation, although dinoflagellate cysts provide general support, particularly at the base of the section. The age model indicates relatively low sedimentation rates (~5 cm/k.y.) at the base of the section with rates at least four to five times greater during intervals of debris flows at ~5-4.6 and ~2.6 Ma. |
format |
Other/Unknown Material |
author |
Channell, James E T Smelror, Morten Jansen, Eystein Higgins, Sean M Lehman, Benoît Eidvin, Tor Solheim, Anders |
author_facet |
Channell, James E T Smelror, Morten Jansen, Eystein Higgins, Sean M Lehman, Benoît Eidvin, Tor Solheim, Anders |
author_sort |
Channell, James E T |
title |
Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
title_short |
Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
title_full |
Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
title_fullStr |
Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
title_full_unstemmed |
Polarity chron boundaries and foraminiferal 87Sr/86Sr ratios of ODP Sites 162-986 and 162-987 |
title_sort |
polarity chron boundaries and foraminiferal 87sr/86sr ratios of odp sites 162-986 and 162-987 |
publisher |
PANGAEA |
publishDate |
1999 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.805085 https://doi.org/10.1594/PANGAEA.805085 |
op_coverage |
MEDIAN LATITUDE: 75.058955 * MEDIAN LONGITUDE: -12.030688 * SOUTH-BOUND LATITUDE: 70.496400 * WEST-BOUND LONGITUDE: -17.937500 * NORTH-BOUND LATITUDE: 77.340600 * EAST-BOUND LONGITUDE: -9.077500 * DATE/TIME START: 1995-08-11T14:25:00 * DATE/TIME END: 1995-09-01T12:15:00 |
long_lat |
ENVELOPE(-17.937500,-9.077500,77.340600,70.496400) |
genre |
Barents Sea Greenland Svalbard |
genre_facet |
Barents Sea Greenland Svalbard |
op_source |
Supplement to: Channell, James E T; Smelror, Morten; Jansen, Eystein; Higgins, Sean M; Lehman, Benoît; Eidvin, Tor; Solheim, Anders (1999): Age models for glacial fan deposits off East Greenland and Svalbard (Sites 986 and 987). In: Raymo, ME; Jansen, E; Blum, P; Herbert, TD (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 162, 1-18, https://doi.org/10.2973/odp.proc.sr.162.008.1999 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.805085 https://doi.org/10.1594/PANGAEA.805085 |
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.80508510.2973/odp.proc.sr.162.008.1999 |
_version_ |
1810434243669524480 |