Characteristics of ice-rafted pebbles from ODP Leg 178 holes
Pebbles (>10 mm) sampled from three drill sites on the continental rise west of the Antarctic Peninsula during Ocean Drilling Program Leg 178 were classified by shape and roundness. In addition, pebble lithology and surface texture were visually identified. To increase the pebble sample number to...
Main Authors: | , |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2001
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.735543 https://doi.org/10.1594/PANGAEA.735543 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.735543 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.735543 2023-05-15T13:42:10+02:00 Characteristics of ice-rafted pebbles from ODP Leg 178 holes Hassler, Lauren E Cowan, Ellen A MEDIAN LATITUDE: -66.861269 * MEDIAN LONGITUDE: -76.659273 * SOUTH-BOUND LATITUDE: -67.566810 * WEST-BOUND LONGITUDE: -78.488080 * NORTH-BOUND LATITUDE: -64.372200 * EAST-BOUND LONGITUDE: -70.261180 * DATE/TIME START: 1998-02-17T16:15:00 * DATE/TIME END: 1998-03-18T10:30:00 2001-03-22 application/zip, 7 datasets https://doi.pangaea.de/10.1594/PANGAEA.735543 https://doi.org/10.1594/PANGAEA.735543 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.735543 https://doi.org/10.1594/PANGAEA.735543 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Hassler, Lauren E; Cowan, Ellen A (2001): Characteristics of ice-rafted pebbles from the continental rise sediment drifts west of the Antarctic Peninsula (Sites 1095, 1096, and 1101). In: Barker, PF; Camerlenghi, A; Acton, GD; Ramsay, ATS (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 178, 1-23, https://doi.org/10.2973/odp.proc.sr.178.212.2001 178-1095A 178-1095B 178-1095D 178-1096A 178-1096B 178-1096C 178-1101A DRILL Drilling/drill rig Joides Resolution Leg178 Ocean Drilling Program ODP South Pacific Ocean Dataset 2001 ftpangaea https://doi.org/10.1594/PANGAEA.735543 https://doi.org/10.2973/odp.proc.sr.178.212.2001 2023-01-20T07:31:42Z Pebbles (>10 mm) sampled from three drill sites on the continental rise west of the Antarctic Peninsula during Ocean Drilling Program Leg 178 were classified by shape and roundness. In addition, pebble lithology and surface texture were visually identified. To increase the pebble sample number to 331, three sites that were drilled 94 to 213 km from the continental shelf edge were integrated into the data set using magnetostratigraphy for core correlation. Pebbles were compared in three groups defined by the same stratigraphic intervals at each site: 3.1-2.2 Ma (late Pliocene), 2.2-0.76 Ma (late Pliocene-late Pleistocene), and 0.76 Ma to the Holocene. Pebble lithologies originate from sources on the Antarctic Peninsula margin. Most pebbles are metamorphic and sedimentary pebbles are rare (<6%), whereas mafic volcanic and intrusive igneous lithologies increase in abundance upsection. Pebbles from 3.1 to 0.76 Ma, plotted on sphericity-roundness diagrams, indicate original transport as basal and supraglacial/englacial debris. Pebbles are abundant and of diverse lithology. From 0.76 Ma to the present, the number of pebbles is low and their shape characteristics indicate they originated as basal debris. Observed changes in ice-rafted pebbles can be explained by growth of an ice sheet and inundation of the Antarctic Peninsula topography by ice ~0.76 Ma. Prior to this, outlet and valley glaciers transported debris at high levels within and at the base of the ice. The mass accumulation rate of sand fluctuates and includes rounded quartz grains. Ice-sheet growth may have been accompanied by overall cooling from subpolar to polar glacial regimes, which halted meltwater production and enhanced the growth of ice shelves, which consequently reduced sediment supply to icebergs. Dataset Antarc* Antarctic Antarctic Peninsula Ice Sheet Ice Shelves Iceberg* PANGAEA - Data Publisher for Earth & Environmental Science Antarctic The Antarctic Antarctic Peninsula Pacific ENVELOPE(-78.488080,-70.261180,-64.372200,-67.566810) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
178-1095A 178-1095B 178-1095D 178-1096A 178-1096B 178-1096C 178-1101A DRILL Drilling/drill rig Joides Resolution Leg178 Ocean Drilling Program ODP South Pacific Ocean |
spellingShingle |
178-1095A 178-1095B 178-1095D 178-1096A 178-1096B 178-1096C 178-1101A DRILL Drilling/drill rig Joides Resolution Leg178 Ocean Drilling Program ODP South Pacific Ocean Hassler, Lauren E Cowan, Ellen A Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
topic_facet |
178-1095A 178-1095B 178-1095D 178-1096A 178-1096B 178-1096C 178-1101A DRILL Drilling/drill rig Joides Resolution Leg178 Ocean Drilling Program ODP South Pacific Ocean |
description |
Pebbles (>10 mm) sampled from three drill sites on the continental rise west of the Antarctic Peninsula during Ocean Drilling Program Leg 178 were classified by shape and roundness. In addition, pebble lithology and surface texture were visually identified. To increase the pebble sample number to 331, three sites that were drilled 94 to 213 km from the continental shelf edge were integrated into the data set using magnetostratigraphy for core correlation. Pebbles were compared in three groups defined by the same stratigraphic intervals at each site: 3.1-2.2 Ma (late Pliocene), 2.2-0.76 Ma (late Pliocene-late Pleistocene), and 0.76 Ma to the Holocene. Pebble lithologies originate from sources on the Antarctic Peninsula margin. Most pebbles are metamorphic and sedimentary pebbles are rare (<6%), whereas mafic volcanic and intrusive igneous lithologies increase in abundance upsection. Pebbles from 3.1 to 0.76 Ma, plotted on sphericity-roundness diagrams, indicate original transport as basal and supraglacial/englacial debris. Pebbles are abundant and of diverse lithology. From 0.76 Ma to the present, the number of pebbles is low and their shape characteristics indicate they originated as basal debris. Observed changes in ice-rafted pebbles can be explained by growth of an ice sheet and inundation of the Antarctic Peninsula topography by ice ~0.76 Ma. Prior to this, outlet and valley glaciers transported debris at high levels within and at the base of the ice. The mass accumulation rate of sand fluctuates and includes rounded quartz grains. Ice-sheet growth may have been accompanied by overall cooling from subpolar to polar glacial regimes, which halted meltwater production and enhanced the growth of ice shelves, which consequently reduced sediment supply to icebergs. |
format |
Dataset |
author |
Hassler, Lauren E Cowan, Ellen A |
author_facet |
Hassler, Lauren E Cowan, Ellen A |
author_sort |
Hassler, Lauren E |
title |
Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
title_short |
Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
title_full |
Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
title_fullStr |
Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
title_full_unstemmed |
Characteristics of ice-rafted pebbles from ODP Leg 178 holes |
title_sort |
characteristics of ice-rafted pebbles from odp leg 178 holes |
publisher |
PANGAEA |
publishDate |
2001 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.735543 https://doi.org/10.1594/PANGAEA.735543 |
op_coverage |
MEDIAN LATITUDE: -66.861269 * MEDIAN LONGITUDE: -76.659273 * SOUTH-BOUND LATITUDE: -67.566810 * WEST-BOUND LONGITUDE: -78.488080 * NORTH-BOUND LATITUDE: -64.372200 * EAST-BOUND LONGITUDE: -70.261180 * DATE/TIME START: 1998-02-17T16:15:00 * DATE/TIME END: 1998-03-18T10:30:00 |
long_lat |
ENVELOPE(-78.488080,-70.261180,-64.372200,-67.566810) |
geographic |
Antarctic The Antarctic Antarctic Peninsula Pacific |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula Pacific |
genre |
Antarc* Antarctic Antarctic Peninsula Ice Sheet Ice Shelves Iceberg* |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Ice Sheet Ice Shelves Iceberg* |
op_source |
Supplement to: Hassler, Lauren E; Cowan, Ellen A (2001): Characteristics of ice-rafted pebbles from the continental rise sediment drifts west of the Antarctic Peninsula (Sites 1095, 1096, and 1101). In: Barker, PF; Camerlenghi, A; Acton, GD; Ramsay, ATS (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 178, 1-23, https://doi.org/10.2973/odp.proc.sr.178.212.2001 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.735543 https://doi.org/10.1594/PANGAEA.735543 |
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.735543 https://doi.org/10.2973/odp.proc.sr.178.212.2001 |
_version_ |
1766163736759894016 |