Le confluent Erdre-Loire, étude pollenanalytique du remplissage sédimentaire atlantique (Nantes-France). - article ; n°3 ; vol.26, pg 121-127

Lionel Visset, Didier Voeltzel

Description

Bulletin de l'Association française pour l'étude du quaternaire - Année 1989 - Volume 26 - Numéro 3 - Pages 121-127
Pollen and radiocarbon analysis of a coring made in the alluvium of a fluvial palaeovalley enables the development of the landscape over the course of the Breton Atlantic to be described. It also provides new informations on sea levels. The standstill, or even regression of the sea between 7630 BP and 7300 BP is particularly well documented, with the establishment of alder carr. The subsequent drowning of the alder carr in about 7300 BP, at - 9 m NGF***, corresponds to the renewed onset of the marine transgression. A new marine standstill phase is evident at about 6300 BP, with the establishment of alder carr once again. At that period the level of the highest seas was between - 4 and - 5 m NGF. The natural accumulation of sediments at this site ceases at approximately - 2 m NGF, at about 6000 BP; the reason for the absence of any sediments from the period 6000 BP to the present day has yet to be explained.
L'étude palynologique et radiocarbone d'un carottage effectué dans les alluvions d'une paléovallée fluviatile permet de décrire, avec précision, l'évolution du paysage au cours de l'Atlantique armoricain et d'apporter de nouvelles données sur la connaissance des niveaux marins.
7 pages
Source : Persée ; Ministère de la jeunesse, de l’éducation nationale et de la recherche, Direction de l’enseignement supérieur, Sous-direction des bibliothèques et de la documentation.

Informations

• Publié par: BULLETIN_DE_L-ASSOCIATION_FRANCAISE_POUR_L-ETUDE_DU_QUATERNAIRE
• Publié le: 01 janvier 1989
• Nombre de lectures: 11
• Langue: Français
• Poids de l'ouvrage: 1 Mo

Extrait

Lionel Visset

Didier Voeltzel

Le confluent Erdre-Loire, étude pollenanalytique du remplissage

sédimentaire atlantique (Nantes-France).

In: Bulletin de l'Association française pour l'étude du quaternaire - Volume 26 - Numéro 3 - 1989. pp. 121-127.

Abstract

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landscape over the course of the Breton Atlantic to be described. It also provides new informations on sea levels. The standstill,

or even regression of the sea between 7630 BP and 7300 BP is particularly well documented, with the establishment of alder

carr. The subsequent drowning of the alder carr in about 7300 BP, at - 9 m NGF***, corresponds to the renewed onset of the

marine transgression. A new marine standstill phase is evident at about 6300 BP, with the establishment of alder carr once again.

At that period the level of the highest seas was between - 4 and - 5 m NGF. The natural accumulation of sediments at this site

ceases at approximately - 2 m NGF, at about 6000 BP; the reason for the absence of any sediments from the period 6000 BP to

the present day has yet to be explained.

Résumé

L'étude palynologique et radiocarbone d'un carottage effectué dans les alluvions d'une paléovallée fluviatile permet de décrire,

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Citer ce document / Cite this document :

Visset Lionel, Voeltzel Didier. Le confluent Erdre-Loire, étude pollenanalytique du remplissage sédimentaire atlantique (Nantes-

France). In: Bulletin de l'Association française pour l'étude du quaternaire - Volume 26 - Numéro 3 - 1989. pp. 121-127.

doi : 10.3406/quate.1989.1900

http://www.persee.fr/web/revues/home/prescript/article/quate_0004-5500_1989_num_26_3_1900