Characterization of a glacial paleo-outburst flood using high-resolution 3-D seismic data: Bjørnelva River Valley, SW Barents Sea
| Title: | Characterization of a glacial paleo-outburst flood using high-resolution 3-D seismic data: Bjørnelva River Valley, SW Barents Sea |
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| Authors: | B. Bellwald, S. Planke, S. Polteau, N. Lebedeva-Ivanova, J.I. Faleide, S.M. Morris, S. Morse, S. Castelltort |
| Source: | Journal of Glaciology, Vol 67, Pp 404-420 (2021) |
| Publisher Information: | Cambridge University Press, 2021. |
| Publication Year: | 2021 |
| Collection: | LCC:Environmental sciences LCC:Meteorology. Climatology |
| Subject Terms: | Arctic glaciology, climate change, fluvial transport, glacier hydrology, Jökulhlaups (GLOFs), Environmental sciences, GE1-350, Meteorology. Climatology, QC851-999 |
| More Details: | Proglacial braided river systems discharge large volumes of meltwater from ice sheets and transport coarse-grained sediments from the glaciated areas to the oceans. Here, we test the hypothesis if high-energy hydrological events can leave distinctive signatures in the sedimentary record of braided river systems. We characterize the morphology and infer a mode of formation of a 25 km long and 1–3 km wide Early Pleistocene incised valley recently imaged in 3-D seismic data in the Hoop area, SW Barents Sea. The fluvial system, named Bjørnelva River Valley, carved 20 m deep channels into Lower Cretaceous bedrock at a glacial paleo-surface and deposited 28 channel bars along a paleo-slope gradient of ~0.64 m km−1. The landform morphologies and position relative to the paleo-surface support that Bjørnelva River Valley was formed in the proglacial domain of the Barents Sea Ice Sheet. Based on valley width and valley depth, we suggest that Bjørnelva River Valley represents a braided river system fed by violent outburst floods from a glacial lake, with estimated outburst discharges of ~160 000 m3 s−1. The morphological configuration of Bjørnelva River Valley can inform geohazard assessments in areas at risk of outburst flooding today and is an analogue for landscapes evolving in areas currently covered by the Greenland and Antarctic ice sheets. |
| Document Type: | article |
| File Description: | electronic resource |
| Language: | English |
| ISSN: | 0022-1430 1727-5652 |
| Relation: | https://www.cambridge.org/core/product/identifier/S002214302000115X/type/journal_article; https://doaj.org/toc/0022-1430; https://doaj.org/toc/1727-5652 |
| DOI: | 10.1017/jog.2020.115 |
| Access URL: | https://doaj.org/article/a70cb099c1224eb396559458aa93bba6 |
| Accession Number: | edsdoj.70cb099c1224eb396559458aa93bba6 |
| Database: | Directory of Open Access Journals |
| ISSN: | 00221430 17275652 |
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| DOI: | 10.1017/jog.2020.115 |
| Published in: | Journal of Glaciology |
| Language: | English |