Academic Journal

Characterization of a glacial paleo-outburst flood using high-resolution 3-D seismic data: Bjørnelva River Valley, SW Barents Sea

التفاصيل البيبلوغرافية
العنوان: Characterization of a glacial paleo-outburst flood using high-resolution 3-D seismic data: Bjørnelva River Valley, SW Barents Sea
المؤلفون: Bellwald, B., Planke, S., Polteau, S., Lebedeva-Ivanova, N., Faleide, J.I., Morris, S.M., Morse, S., Castelltort, S.
المصدر: Journal of Glaciology ; volume 67, issue 263, page 404-420 ; ISSN 0022-1430 1727-5652
بيانات النشر: Cambridge University Press (CUP)
سنة النشر: 2021
الوصف: 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 m 3 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.
نوع الوثيقة: article in journal/newspaper
اللغة: English
DOI: 10.1017/jog.2020.115
الاتاحة: http://dx.doi.org/10.1017/jog.2020.115
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S002214302000115X
Rights: http://creativecommons.org/licenses/by/4.0/
رقم الانضمام: edsbas.C4B2BCD8
قاعدة البيانات: BASE