Can we estimate catchment-scale biomass production from sedimentary biomarkers? An attempt with miliacin in Late Bronze Age levels from Lake le Bourget (French Alps).

Jérémy Jacob (1) , Emmanuel Chapron (1) , Yves Billaud (2, 3) , Grégoire Ledoux (4) , Patrick Lajeunesse (4) , Jean-Robert Disnar (1) , Guillaume St-Onge (5) , Claude Le Milbeau (1) , Nicolas Bossard (1) , Fabien Arnaud (3)

1 ISTO - Institut des Sciences de la Terre d'Orléans
2 DRASSM - Département des Recherches Archéologiques Subaquatiques et Sous-Marines [Marseille]
3 EDYTEM - Environnements, Dynamiques et Territoires de la Montagne
4 Centre d'études nordiques et Département de Géographie
5 ISMER - Institut des Sciences de la MER de Rimouski

The evaluation of demography for proto- and prehistoric times remains complex due to the rareness of human remains. Here we propose an original approach based on the combination of geophysical and organic geochemical techniques applied to the Late Bronze Age sedimentary infill of Lake le Bourget. Deep sediments were mapped and their volume estimated by sub-bottom seismic profiling calibrated (accoustically and chronologically) on piston cores. Multibeam bathymetry combined to a subaquatic archaeological survey allowed to precisely identify the extension of Late Bronze Age palafittic stations in shallow waters and to determine the volume of the associated organic rich deposits.

Domains: Continental interfaces, environment; Global Changes

Jérémy Jacob, Emmanuel Chapron, Yves Billaud, Grégoire Ledoux, Patrick Lajeunesse, et al.. Can we estimate catchment-scale biomass production from sedimentary biomarkers? An attempt with miliacin in Late Bronze Age levels from Lake le Bourget (French Alps).. The 25th International Meeting on Organic Geochemistry, Sep 2011, Interlaken, Switzerland. 2p. ⟨insu-00842947⟩