Saved in:
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Dataset Open Access |
| Language: | en |
| Published: |
PANGAEA
2018
|
| Subjects: | |
| Online Access: | https://doi.org/10.1594/PANGAEA.891154 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1867168571778400256 |
|---|---|
| author | Leng, Wei von Dobeneck, Tilo Bergmann, Fenna Just, Janna Mulitza, Stefan Chiessi, Cristiano Mazur St-Onge, Guillaume Piper, David J W |
| author_facet | Leng, Wei von Dobeneck, Tilo Bergmann, Fenna Just, Janna Mulitza, Stefan Chiessi, Cristiano Mazur St-Onge, Guillaume Piper, David J W |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Eastern Canadian margin sediments bear testimony to several catastrophic deglacial meltwater discharges from the retreating Laurentide Ice Sheet. The reddish-brown plumite layers deposited on the levees of the Laurentian Fan valleys have been recognized as indications of multiple outburst floods between Heinrich events 2 and 1. Five event layers have been consistently recorded in three new gravity cores retrieved on the SW Grand Banks slope and comply with the previously published Laurentian Fan core MD95-2029. The apparently huge extent of these outburst plumes around the Laurentian Fan as well as their causes and consequences are investigated in this study using physical properties, rock magnetic and grain-size analyses, together with seismoacoustic profiling. We provide the first detailed 14C ages of the outburst event sequence and discuss their recurrence intervals in the context of regional ice retreat. Compared to the hemipelagic interlayers, event layers have overall uniform and systematic changes of rock-magnetic properties. Hematite contents increase over time and proximally while magnetite grain sizes fine upwards and spatially away from the fan. Based on the sediment composition and load, we argue that these plumites were formed by recurrent erosion of glacial mud deposits in the Laurentian Channel by meltwater outbursts. Three alternative glaciological scenarios are evaluated: in each case, the provenance of the transported sediment is not an indicator of the precise source of the meltwater. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_891154 |
| institution | PANGAEA |
| language | en |
| publishDate | 2018 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | Physical properties of sediment cores GeoB18514-2, GeoB18515-1, GeoB18516-2, and MD95-2029 Leng, Wei von Dobeneck, Tilo Bergmann, Fenna Just, Janna Mulitza, Stefan Chiessi, Cristiano Mazur St-Onge, Guillaume Piper, David J W Center for Marine Environmental Sciences; GeoB; Geosciences, University of Bremen; IMAGES; International Marine Global Change Study; MARUM Eastern Canadian margin sediments bear testimony to several catastrophic deglacial meltwater discharges from the retreating Laurentide Ice Sheet. The reddish-brown plumite layers deposited on the levees of the Laurentian Fan valleys have been recognized as indications of multiple outburst floods between Heinrich events 2 and 1. Five event layers have been consistently recorded in three new gravity cores retrieved on the SW Grand Banks slope and comply with the previously published Laurentian Fan core MD95-2029. The apparently huge extent of these outburst plumes around the Laurentian Fan as well as their causes and consequences are investigated in this study using physical properties, rock magnetic and grain-size analyses, together with seismoacoustic profiling. We provide the first detailed 14C ages of the outburst event sequence and discuss their recurrence intervals in the context of regional ice retreat. Compared to the hemipelagic interlayers, event layers have overall uniform and systematic changes of rock-magnetic properties. Hematite contents increase over time and proximally while magnetite grain sizes fine upwards and spatially away from the fan. Based on the sediment composition and load, we argue that these plumites were formed by recurrent erosion of glacial mud deposits in the Laurentian Channel by meltwater outbursts. Three alternative glaciological scenarios are evaluated: in each case, the provenance of the transported sediment is not an indicator of the precise source of the meltwater. |
| title | Physical properties of sediment cores GeoB18514-2, GeoB18515-1, GeoB18516-2, and MD95-2029 |
| topic | Center for Marine Environmental Sciences; GeoB; Geosciences, University of Bremen; IMAGES; International Marine Global Change Study; MARUM |
| url | https://doi.org/10.1594/PANGAEA.891154 |