Details of Sedimentological and palynological records since 8.5 ka BP along a proximal-distal gradient on the northern Bay of Biscay (NW Europe)

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Dataset identification

Title of datasetSedimentological and palynological records since 8.5 ka BP along a proximal-distal gradient on the northern Bay of Biscay (NW Europe)
Narrative summary of datasetNew results acquired in south-Brittany (MD08-3204 CQ core: Bay of Quiberon and VK03-58bis core: south Glénan islands) allow depicting Holocene paleoenvironmental changes from 8.5 ka BP to present through a multi-proxy dataset including sedimentological and palynological data. First, grain-size analyses and AMS-14C dates highlight a common sedimentary history for both study cores. The relative sea level (RSL) slowdown was accompanied by a significant drop of the sedimentation rates between ca. 8.3 and 5.7 ka BP, after being relatively higher at the onset of the Holocene. This interval led to the establishment of a shell-condensed level, identified in core VK03-58bis by the “Turritella layer” and interpreted as a marker for the maximum flooding surface. Palynological data (pollen grains and dinoflagellate cyst assemblages) acquired in core MD08-3204 CQ argue for an amplification of the fluvial influence since 5.7 ka BP; the establishment of the highstand system tract (i.e., mixed marine and fluviatile influences on the platform) then accompanying the slowdown of the RSL rise-rates. On the shelf, the amplification of Anthropogenic Pollen Indicators (API) is then better detected since 4.2 ka BP, not only due to human impact increase but also due to a stronger fluvial influence on the shelf during the Late Holocene. Palynological data, recorded on the 8.5–8.3 ka BP interval along an inshore-offshore gradient, also demonstrate the complexity of the palynological signal such as i) the fluvial influence that promotes some pollinic taxa (i.e., Corylus, Alnus) from proximal areas and ii) the macro-regionalization of palynomorph sources in distal cores. In addition, the comparison of palynological tracers, including API, over the last 7 kyrs, with south-Brittany coastal and mid-shelf sites subjected to northern vs. southern Loire catchment areas, allowed discussing a major hydro-climatic effect on the reconstructed palynological signals. Strengthened subpolar gyre dynamics (SPG), combined with recurrent positive North Atlantic Oscillation (NAO) configurations, appear responsible for increased winter precipitations and fluvial discharges over northern Europe, such as in Brittany. Conversely, weakened SPG intervals, associated with negative NAO-like modes, are characterized by intensified winter fluvial discharges over southern Europe. Interestingly, we record, at an infra-orbital timescale, major peaks of API during periods of strengthened (/weakened) SPG dynamics in sites subjects to Brittany watersheds (/Loire watersheds) inputs. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.
Cruise
Start date2003-10-23
End date2008-07-24

Responsible organisations

CountryFrance
Organisation nameIfremer, Scientific Information Systems for the sea
Role of organisationDataset Holding Organisation
CountryFrance
Organisation nameSEA scieNtific Open data Edition
Role of organisationPublisher
How to citeDavid Ophélie, Penaud Aurélie, Vidal Muriel, Wiem Fersi, Lambert Clément, Goubert Evelyne, Herledan Maiwenn, Stephan Pierre, Pailler Yvan, Bourillet Jean-Francois, Baltzer Agnès (2022). Sedimentological and palynological records since 8.5 ka BP along a proximal-distal gradient on the northern Bay of Biscay (NW Europe). SEANOE. https://doi.org/10.17882/86430

Dataset availability

Original dataset download linkhttps://cloud.emodnet-ingestion.eu/index.php/s/9XcG7ZGfTscUyHy
Dataset formatDocuments
Public accessNo limitations
License for useCC-BY 4.0
TypeDataset
DOIhttps://doi.org/10.17882/86430

Locations

Map
Latitude north boundary48
Longitude east boundary-2
Latitude south boundary44
Longitude west boundary-6
Sea areaNorth Atlantic Ocean
Bay of Biscay
Atlantic Ocean
European mainland
Northeast Atlantic Ocean (40W)
Vertical extent minimum20 Centimetres
Vertical extent maximum287 Centimetres

Data types, collection and processing

Observation typeinapplicable
ParameterSediment grain size parameters
Sediment age
Sediment pollen content
Platform typeresearch vessel
Data quality processing informationRaw data

Process information

Submitting organisationGeo-Ocean - UMR 6538
Submission identifier (UUID)a53ad03f-3836-8363-3634-000000086430
Date of dataset creation2022-01-01
Date of dataset revision2022-06-08
Date of metadata creation2022-6-10
Date of metadata latest revision2023-03-30
Date of publishing2023-04-16
Processing data centreIfremer, Scientific Information Systems for the sea
Summary record-ID1308