(Table 1) Rare earth element contents in basalts and glasses of DSDP Legs 45 and 51

Rare-earth element (REE) distributions in altered basalts and glasses collected during some Legs of the Deep Sea Drilling Project show that a fractionation of these elements occurs during submarine weathering. When the alteration is well-marked, the REE distribution in altered glasses shows an enrichment in light rare-earths relative to the fresh glass. In particular, Ce is selectively enriched in palagonitized glasses that comprise, besides polymetallic nodules, another phase liable to explain the Ce depletion in seawater. Taking in account these processes of submarine weathering of the oceanic crust, a geochemical balance of Ce between authigenic phases of the marine environment is attempted

« Contribution à la réalisation de la phase opérationnelle du REBENT Bretagne 2006 ».

30 p.Rapport final phase 5, CNRS/Ifremer

« Actualisation de la cartographie morpho-sédimentaire de l'estran en baie du Mont Saint-Michel ».

International audienc

Le laboratoire de géomorphologie de l'E.P.H.E. en 1991 et 1992

Bonnot-Courtois C. Le laboratoire de géomorphologie de l'E.P.H.E. en 1991 et 1992. In: Norois, n°160, Octobre-Décembre 1993. pp. 673-685

(Table 1) Major and trace elements analyses from FAMOUS-Project and DSDP Site 54-424

Hydrothermal deposits "sensu stricto" have been recovered during the FAMOUS cruise and Leg 54 of the Deep Sea Drilling Project near the Galapagos Spreading Centre. The studied sediments, mainly composed of clay material, have very poor REE concentrations, below about ten ppm. The shale-normalized patterns are characterized by a significant enrichment in heavy rare earths and show a negative Ce anomaly. The magnitude of this anomaly fluctuates but is generally lower than the seawater Ce anomaly. The geochemical characteristics of these hydrothermal deposits are in contrast with those of metalliferous sediments which are more enriched in trace elements, especially in REE

« Erosion littorale. Evaluation du risque. Phase 2 : Caractérisation de l'aléa érosion sur le littoral des Côtes d'Armor ».

29 p.Rapport DDE 22/UMR 8586 PRODIG CNRS

« Contribution à la réalisation de la phase opérationnelle du Rebent Bretagne 2004. Cartographie bio-morpho-sédimentaire des estrans dans le cadre du réseau benthique. »

30 p.Rapport final Phase 3. CNRS/Ifreme