Orbital imprint on Holocene paleohydrological variations in west-central Europe as reflected by lake-level changes at Cerin-Jura Mountains, eastern France
Résumé
This paper presents a lake-level record for the Holocene at Lake Cerin Jura Mountains, eastern France. It is based on a range of sedimentological techniques validated in previous studies, with a combination of systematic lithostratigraphic investigations of the infillings accumulated in the lacustrine basin, and sediment analyses of two selected cores. The chronology is based on 10 radiocarbon dates and pollen stratigraphy. On a millennial scale, the Cerin lake-level record shows three distinct successive phases characterised by higher lake-level conditions until ca. 9000 cal. a BP, followed by a maximal lowering at ca. 90008500 cal. a BP, and a progressive rise until the present. This rise was punctuated by centennial-scale fluctuations, with major events around 4000, 2800 and after 1500 cal. a BP. Considered on a multimillennial scale, the general pattern of palaeohydrological changes reconstructed at Cerin reflects the impact of orbitally driven summer insolation. This is in agreement with other regional and extra-regional palaeoclimatic records, although every record shows peculiarities in timing and shape depending on the proxy used for reconstruction. In this general context, centennial to multicentennial oscillations appear to have been second-order events in comparison with the major influence of the orbital factor.