ESR/U-series dating of palaeontological remains from the Neandertalian site of Mutzig-Rain (Alsace, France).

The Middle Palaeolithic site of Mutzig, discovered in 1992, has been the focus of several pits and excavations since 2010, delivering numerous well preserved palaeontological remains and more than 4500 lithic artifacts. The site is made by several rock shelters now collapsed (called "M1" to "M12"), each of them containing several Middle Palaeolithic occupation levels. The faunal assemblage of the main archaeological levels (7a to 7f) from the current excavation (M2) includes woolly mammoth, reindeer, horse, bison and woolly rhinoceros, reflecting a cold steppe context, while microfauna from the lower levels (7D and 10) indicate the presence of forests and suggest a more temperate climate. An OSL dating study places the archaeological sequence as coeval of the onset of the last glacial stage, the Weichselian, during MIS 5, between 105 and 80 ka. The good state of preservation of the abundant faunal remains at Mutzig provided good supports for ESR and U-series dating method. The first results obtained by U-series in 1995 on bones were not encouraging. A first set of teeth (from "M2" site), considered today as more appropriate dating material was therefore analyzed by combined ESR/U-series, using alpha spectrometry in 2013-2015, and yielded ages around 96-100 ka for levels 5-7, in agreement with the OSL data [1]. These analyses showed a quite systematic U-leaching from the dental tissues and the ages were calculated by the "Accelerated Uptake (AU) model" [2]. A second set of teeth from "M2" and "M8" sites was recently analyzed by combined ESR with U-series using quadripolar mass spectrometry (ICP-Q-MS) in MNHN laboratory. The whole set of ESR/U-series data obtained on Mutzig teeth is presented and discussed versus OSL dates allowing a better resolution of the chronology of the site. [ABSTRACT FROM AUTHOR]