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Appeared in: Open Search Symposium 2019, 23-24 October 2019, Garching / Munich, Germany. &nbsp

Work on thermal pools at Poggetti Vecchi in Grosseto, Italy, exposed an up to 3-meter-thick succession of seven sedimentary units. Unit 2 in the lower portion of the succession contained vertebrate bones, mostly of the straight-tusked elephant, Palaeoloxodon antiquus, commingled with stone, bone, and wooden tools. Thermal carbonates overlying Unit 2 are radiometrically dated to the latter part of the middle Pleistocene. This time span indicates that early Neanderthals produced the human artifacts from Poggetti Vecchi. The elephant bones belong to seven individuals of different ages. Sedimentary facies analysis and paleoecological evidence suggest a narrow lacustrine-palustrine embayment affected by water-level fluctuations and, at times, by hydrothermal water. Cyclic lake-level variations were predominantly forced by the rapid climatic fluctuations that occurred at Marine Isotope Stage (MIS) 6–7 transition and throughout the MIS 6. Possibly an abrupt, intense, and protracted cold episode during the onset of MIS 6 led to the sudden death of the elephants, which formed an unexpected food resource for the humans of the area. The Poggetti Vecchi site adds new information on the behavioral plasticity and food procurement strategies that early Neanderthals were able to develop in Italy during the middle to the late Pleistocene transition.

A buried paleovalley system, up to 2 km wide and exceeding 50 m in relief, made up of multiple cross-cutting depressions incised into the Lower Pleistocene bedrock, is reported from the central Adriatic coastal plain at the mouth of Biferno River. Through a multi-proxy approach that included geomorphological, stratigraphic, sedimentological and paleontological (benthic foraminifers, ostracods and molluscs) investigations, the facies architecture of distinct, superposed valley fills is reconstructed and their relative chronology established along a transverse profile with extremely high data density (average borehole spacing 75 m). Regional tectonic uplift appears as the major controlling factor of initial (Middle Pleistocene) river down-cutting and paleovalley formation. In contrast, glacio-eustatic fluctuations drove fluvial-system response over the last 120 ky, when valley incision was primarily induced by the last glacial base-level lowering and climatic forcing. A fragmented record of coastal and shallow-marine deposits is available for the lower paleovalley fill, which is penetrated by a limited borehole dataset. Multiple erosion phases probably related to the post-MIS 5e sea-level fall are reconstructed from the upper paleovalley fill, where a buried fluvial terrace succession is identified a few tens of meters below the ground surface. The flat surfaces of two buried fluvial terraces suggest longer-term, stepped relative sea-level fall, and are correlated with fluvial incisions that took place possibly at the MIS 5/4 transition and at the MIS 3/2 transition, respectively. A laterally extensive gravel body developed on the valley floor during the Last Glacial Maximum. During the ensuing latest Pleistocene–early Holocene sea-level rise the Biferno paleovalley was transformed into an estuary. Upstream from the maximum shoreline ingression, the vertical succession of well-drained floodplain, poorly-drained floodplain, and swamp deposits evidences increasing marine influence in the estuary, in response to continuing sea-level rise. The interfluves were drowned around 8 cal. ky BP, when brackish conditions developed in the study area. Decreasing marine influence in the uppermost 15 m of the paleovalley fill suggests the onset of the modern delta: when the rate of sea-level rise was overwhelmed by sediment supply, delta progradation took place.