Integrated geochronology of Acheulian sites from the southern Latium (central Italy). Insights on human-environment interaction and the technological innovations during the MIS 11-MIS 10 period

We have explored the multimethod approach combining 40Ar/39Ar on single crystal, ESR on bleached quartz, and ESR/U-series on teeth to improve the age of four neighbours “Acheulian” sites of the Frosinone Province (Latium, Italy): Fontana Ranuccio, Cava Pompi (Pofi), Isoletta, and Lademagne. Ages obtained by the three methods are in mutual agreement and confirm the potential of dating with confidence Middle Pleistocene sites of Italy using these methods. At Fontana Ranuccio, the 40Ar/39Ar age (408 ± 10 ka, full external error at 2σ) obtained for the archaeological level (unit FR4) and geochemical analyses of glass shards performed on the Unit FR2a layer allow us to attribute the studied volcanic material to the Pozzolane Nere volcanic series, a well-known caldera-forming event originated from the Colli Albani volcanic district. These new data ascribe the Fontana Ranuccio site, as well as the eponym faunal unit, to the climatic optimum of Marine Isotope Stage (MIS) 11. Ages obtained for the Cava Pompi, Isoletta, and Lademagne sites cover a relatively short period of time between 408 ka and 375 ka, spanning MIS 11 climatic optimum to the MIS 11–10 transition. Analysis of small collections of lithic industries, bifacial tools, and small cores technologies from Isoletta, Lademagne, and the neighbour site of Ceprano-Campogrande shows common technical strategies for the period comprised between MIS 11 and MIS 9 (410–325 ka), such as the elaboration of flaked elephant bone industries found over the whole Latium region. However, some features found only in the Frosinone province area, like large-sized bifaces, suggest particular regional behaviours. The presence of one Levallois core in the oldest layer of Lademagne (i.e. > 405 ± 9 ka) suggests a punctual practice of this technology, also proposed as early as MIS 10/11 in the neighbour site of Guado San Nicola (Molise) in central Italy.