Terrigenous fluxes at the Celtic margin during the last glacial cycle

Author(s): Auffret, Gérard; Zaragosi, Sébastien; Dennielou, Bernard; Cortijo, Elsa; van Rooij, David; Grousset, Francis; Pujol, Claude; Eynaud, Frédérique; Siegert, Martin J.
Author Affiliation(s): Primary:
Université de Bordeaux I, Département de Géologie et Océanographie, Talence, France
Other:
IFREMER, France
Centre des faibles Radioactivités, France
University of Gent, Belgium
University of Bristol, United Kingdom
Volume Title: European North Atlantic Margin (ENAMII); quantification and modelling of large-scale sedimentary processes
Volume Author(s): Mienert, Jurgen, editor
Source: European North Atlantic Margin (ENAMII); quantification and modelling of large-scale sedimentary processes, edited by Jurgen Mienert. Marine Geology, 188(1-2), p.79-108. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0025-3227 CODEN: MAGEA6
Note: In English. 125 refs.; illus., incl. 7 tables, sketch map
Summary: The sedimentary sections of three cores from the Celtic margin provide high-resolution records of the terrigenous fluxes during the last glacial cycle. A total of 21 14C AMS dates allow us to define age models with a resolution better than 100 yr during critical periods such as Heinrich events 1 and 2. Maximum sedimentary fluxes occurred at the Meriadzek Terrace site during the Last Glacial Maximum (LGM). Detailed X-ray imagery of core MD95-2002 from the Meriadzek Terrace shows no sedimentary structures suggestive of either deposition from high-density turbidity currents or significant erosion. Two paroxysmal terrigenous flux episodes have been identified. The first occurred after the deposition of Heinrich event 2 Canadian ice-rafted debris (IRD) and includes IRD from European sources. We suggest that the second represents an episode of deposition from turbid plumes, which precedes IRD deposition associated with Heinrich event 1. At the end of marine isotopic stage 2 (MIS 2) and the beginning of MIS 1 the highest fluxes are recorded on the Whittard Ridge where they correspond to deposition from turbidity current overflows. Canadian icebergs have rafted debris at the Celtic margin during Heinrich events 1, 2, 4 and 5. The high-resolution records of Heinrich events 1 and 2 show that in both cases the arrival of the Canadian icebergs was preceded by a European ice rafting precursor event, which took place about 1-1.5 kyr before. Two rafting episodes of European IRD also occurred immediately after Heinrich event 2 and just before Heinrich event 1. The terrigenous fluxes recorded in core MD95-2002 during the LGM are the highest reported at hemipelagic sites from the northwestern European margin. The magnitude of the Canadian IRD fluxes at Meriadzek Terrace is similar to those from oceanic sites.
Year of Publication: 2002
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 24 Surficial Geology, Quaternary Geology; Absolute age; Accelerator mass spectra; Atlantic Ocean; C-14; Carbon; Celtic Sea; Cenozoic; Continental margin; DSDP Site 609; Dates; Deep Sea Drilling Project; Europe; Glacial sedimentation; Glaciation; Glaciomarine sedimentation; IPOD; Isotopes; Last glacial maximum; Leg 94; Marine sedimentation; Marine sediments; Mass spectra; North Atlantic; Northeast Atlantic; Paleoenvironment; Quaternary; Radioactive isotopes; Sedimentation; Sediments; Spectra; Western Europe
Coordinates: N495240 N495241 W0241417 W0241418
Record ID: 2002067222
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands