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author Lenz, Kai-Frederik
Gebhardt, Andrea Catalina
Lajeunesse, Patrick
Lohrberg, Arne
Gross, Felix
Krastel, Sebastian
author_facet Lenz, Kai-Frederik
Gebhardt, Andrea Catalina
Lajeunesse, Patrick
Lohrberg, Arne
Gross, Felix
Krastel, Sebastian
collection Datos científicos de ciencias marinas y ambientales
contents Lakes in formerly glaciated regions can provide valuable paleoclimate archives. Lake Manicouagan (Manikuakan, according to Innu toponymy), formed in the basin of the ~214‐Ma Manicouagan impact crater of eastern Québec, is a key area for reconstructing long‐term environmental change, as it was directly affected by the Pleistocene glaciations and the waxing and waning of the Laurentide Ice Sheet. Here, we present high‐resolution seismic data revealing an overdeepened bedrock valley filled with a sedimentary sequence. We assess its potential to serve as a paleoclimate archive. The varying shape of the overdeepened valley indicates complex erosional processes. A lower narrow V‐shaped gorge is indicative of either pressurized subglacial meltwater or pre‐Quaternary fluvial erosion, or a combination of both. Three scenarios are discussed regarding deposition of the sedimentary sequence: deposition only during and after retreat of the last glacial episode; (ii) deposition during multiple glacial–interglacial cycles; and (iii) deposition mainly during a subglacial lake stage. We suggest subglacial followed by proglacial sedimentation as the most probable scenario for deposition of the sedimentary succession. We recommend considering the sediments of Lake Manicouagan as a paleoclimate archive reaching back at least to 7.5 ka, but the lake also probably contains sediments deposited before the last deglacial period. The published data include all thirty high-resolution seismic profiles acquired in 2016.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_946132
institution PANGAEA
language en
publishDate 2023
publisher PANGAEA
record_format pangaea
spellingShingle High-resolution multichannel seismic profiles from Lake Manicouagan, Canada
Lenz, Kai-Frederik
Gebhardt, Andrea Catalina
Lajeunesse, Patrick
Lohrberg, Arne
Gross, Felix
Krastel, Sebastian
AWI-20168110; AWI-20168120; AWI-20168130; AWI-20168140; AWI-20168150; AWI-20168160; AWI-20168170; AWI-20168180; AWI-20168190; AWI-20168200; AWI-20168210; AWI-20168220; AWI-20168230; AWI-20168240; AWI-20168250; AWI-20168260; AWI-20168270; AWI-20168280; AWI-20168290; AWI-20168300; AWI-20168310; AWI-20168320; AWI-20168330; AWI-20168340; AWI-20168350; AWI-20168360; AWI-20168370; AWI-20168380; AWI-20168390; AWI-20168400; Binary Object; Binary Object (File Size); Canada; Date/Time of event; Date/Time of event 2; Event label; glacial geomorphology; high-resolution reflection seismic; Lake_Manic; Lake Manicouagan; Latitude of event; Latitude of event 2; Laurentide Ice Sheet; Longitude of event; Longitude of event 2; Louis-Edmond-Hamelin; paleoclimate archive; Seismic reflection profile; SEISREFL; subglacial lake
Lakes in formerly glaciated regions can provide valuable paleoclimate archives. Lake Manicouagan (Manikuakan, according to Innu toponymy), formed in the basin of the ~214‐Ma Manicouagan impact crater of eastern Québec, is a key area for reconstructing long‐term environmental change, as it was directly affected by the Pleistocene glaciations and the waxing and waning of the Laurentide Ice Sheet. Here, we present high‐resolution seismic data revealing an overdeepened bedrock valley filled with a sedimentary sequence. We assess its potential to serve as a paleoclimate archive. The varying shape of the overdeepened valley indicates complex erosional processes. A lower narrow V‐shaped gorge is indicative of either pressurized subglacial meltwater or pre‐Quaternary fluvial erosion, or a combination of both. Three scenarios are discussed regarding deposition of the sedimentary sequence: deposition only during and after retreat of the last glacial episode; (ii) deposition during multiple glacial–interglacial cycles; and (iii) deposition mainly during a subglacial lake stage. We suggest subglacial followed by proglacial sedimentation as the most probable scenario for deposition of the sedimentary succession. We recommend considering the sediments of Lake Manicouagan as a paleoclimate archive reaching back at least to 7.5 ka, but the lake also probably contains sediments deposited before the last deglacial period. The published data include all thirty high-resolution seismic profiles acquired in 2016.
title High-resolution multichannel seismic profiles from Lake Manicouagan, Canada
topic AWI-20168110; AWI-20168120; AWI-20168130; AWI-20168140; AWI-20168150; AWI-20168160; AWI-20168170; AWI-20168180; AWI-20168190; AWI-20168200; AWI-20168210; AWI-20168220; AWI-20168230; AWI-20168240; AWI-20168250; AWI-20168260; AWI-20168270; AWI-20168280; AWI-20168290; AWI-20168300; AWI-20168310; AWI-20168320; AWI-20168330; AWI-20168340; AWI-20168350; AWI-20168360; AWI-20168370; AWI-20168380; AWI-20168390; AWI-20168400; Binary Object; Binary Object (File Size); Canada; Date/Time of event; Date/Time of event 2; Event label; glacial geomorphology; high-resolution reflection seismic; Lake_Manic; Lake Manicouagan; Latitude of event; Latitude of event 2; Laurentide Ice Sheet; Longitude of event; Longitude of event 2; Louis-Edmond-Hamelin; paleoclimate archive; Seismic reflection profile; SEISREFL; subglacial lake
url https://doi.org/10.1594/PANGAEA.946132