Skip to Main content Skip to Navigation
Journal articles

High-resolution bathymetry of the Alderney Race and its geological and sedimentological description (Raz Blanchard, northwest France)

Abstract : We present a high-resolution 1:15,000 bathymetric map (Main map) of Alderney Race located offshore of northwestern France, with the strongest currents in Europe. We use this map, underwater video transects and Shipek grabs to improve geological maps previously published. We distinguished Proterozoic crystalline rocks, Paleozoic and Cretaceous sedimentary rocks on the present-day sea floor. Some structures as faults and folds are also mapped. We identified a Quaternary cover made of pebbles, boulders and blocks interpreted as corestones resulting in differential erosion and alteration of the substratum. This cover is commonly encrusted by fixed fauna, such as bryozoans and barnacles. Finally, we describe the present-day mobile sediment cover characterized by sand patches and pebble dune fields (up to 10 m in height). Our videos show the presence of mobile fine-grained sediment patches under the resolution of our map lying between the cobble and pebble cover. We summarize our interpretations on a non-exhaustive geological-sedimentary map
Complete list of metadatas

https://hal-normandie-univ.archives-ouvertes.fr/hal-02433417
Contributor : Pascal Bailly Du Bois <>
Submitted on : Thursday, January 9, 2020 - 9:59:05 AM
Last modification on : Friday, September 18, 2020 - 2:34:16 PM
Long-term archiving on: : Saturday, April 11, 2020 - 1:39:43 PM

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Collections

Citation

Lucille Furgerot, Yohann Poprawski, Marc Violet, Emmanuel Poizot, Pascal Bailly Du Bois, et al.. High-resolution bathymetry of the Alderney Race and its geological and sedimentological description (Raz Blanchard, northwest France). Journal of Maps, Taylor & Francis, 2019, 15 (2), pp.708-718. ⟨10.1080/17445647.2019.1657510⟩. ⟨hal-02433417⟩

Share

Metrics

Record views

74

Files downloads

242