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

E’ stato effettuato uno studio interdisciplinare integrato, che ha compreso analisi geomorfologiche, stratigrafiche, paleontologiche, palinologiche e geocronologiche su successioni sedimentarie provenienti da 2 settori della costa molisana: l'area della foce del fiume Trigno e l'area del Porto di Termoli. Le analisi sono state compiute su complessive 6 successioni da carote, di cui 3 prelevate a mare, a poche centinaia di metri dalla attuale linea di costa nell’area del fiume Trigno, e altre 3 a terra, vicino all'attuale linea di costa, nell’area del porto di Termoli. I risultati ottenuti hanno consentito di ricostruire alcune delle tappe fondamentali dell'evoluzione paleoambientale delle aree di studio nel tardo Pleistocene superiore e nell'Olocene. In particolare, le analisi paleontologiche hanno ricoperto un ruolo fondamentale sia ai fini delle ricostruzioni paleo-ambientali in generale, sia per evidenziare in particolare una serie di variazioni paleobatimetriche, interpretabili come tendenze regressive e trasgressive, controllate da cambiamenti climatici, che hanno interessato l'area di studio durante gli ultimi 8000 anni. Nell'area della foce del fiume Trigno, durante l'ultima fase glaciale, era presente una topografia articolata legata ad una dinamica fluviale attiva. Dopo l'Ultimo Massimo Glaciale (LGM), intorno ai 20000 anni fa, per ca. un millennio, nelle aree incise dall'azione fluviale si impostarono ambienti di tipo fluvio-palustre popolati da faune continentali e in cui si depositavano sedimenti fini di tipo limoso. Il livello del mare era inferiore rispetto a quello attuale di ca. 100 m e la linea di costa spostata ad Est rispetto alla sua posizione attuale di alcune decine di km. La successiva fase evolutiva dell'area è legata alla risalita del livello del mare conseguente alla trasgressione marina olocenica postglaciale. Nell'area dapprima si impostarono degli ambienti simili, per caratteristiche idrodinamiche e morfologiche, a quelli lagunari, ma con condizioni di salinità di tipo marino. Intorno agli 8000 anni fa si impostarono ambienti marini tipici di spiaggia sommersa in cui si depositavano sedimenti sabbiosi. Tali ambienti erano popolati da faune infralitorali. Inizialmente le batimetrie erano ridotte ed il livello del mare era inferiore rispetto a quello attuale di 11/12 m. Nella prima fase della trasgressione, le batimetrie aumentavano, il mare avanzava e gli ambienti costiero-marginali e la linea di riva si spostavano verso terra. Successivamente si sviluppò una tendenza regressiva e le batimetrie diminuirono in risposta al deterioramento climatico verificatosi tra 6800 e 7000 anni fa ca. In tale fase il livello del mare nell’area di studio stazionava a ca. -7,5/8,0 m rispetto a quello attuale. Dopo la fase di optimum climatico di ca. 6000 anni fa, le facies marino-costiere progradarono e le batimetrie diminuirono rispetto a quelle della fase precedente, probabilmente in risposta al deterioramento climatico collegato all’inizio della neoglaciazione ca. 5000-5500 anni fa. Il livello del mare durante questa fase era di ca. – 4/5 m s.l.m. L’evoluzione successiva è caratterizzata da una permanenza dell’ambiente litorale con lievi oscillazioni della linea di costa. A questo punto dell'evoluzione era presente un ambiente fluvio-deltizio e nell'area di studio si verificavano fasi di emersione temporanee. L’evoluzione chiude con la fase recente (probabilmente successiva alla piccola età glaciale) in cui la linea di riva avanza verso terra e si imposta la costa attuale. Nell'area del porto di Termoli i risultati sono ancora preliminari e evidenziano un quadro evolutivo paleoambientale piuttosto complesso ed eterogeno. Lo studio effettuato ha consentito di individuare ripetute fasi di avanzamento ed arretramento della linea di riva durante il Pleistocene superiore e l'Olocene. Durante le fasi di emersione i sedimenti subivano fenomeni di parziale pedogenesi. L'arrivo della trasgressione marina olocenica nell'area di studio è stato individuato nel periodo in cui il livello del mare era inferiore rispetto a quello attuale di circa 11 m. Tale dato è consistente con quello ricavato per l'area della foce del fiume Trigno dove il mare raggiunge le coste attuali intorno agli 8000 anni fa quando il livello del mare era inferiore rispetto a quello attuale di 11-12 m. Nell'area del Porto di Termoli sono state individuate una serie di oscillazioni marine che si sono verificate in intervalli temporali precedenti a quelli della trasgressione marina olocenica. Attualmente non è possibile inquadrare cronologicamente in maniera precisa queste oscillazioni; è possibile comunque affermare che esse si sono verificate prima dell'ultima fase glaciale. Si tratta del primo studio che affronta in modo specifico l’aspetto della evoluzione tardo-pleistocenica ed olocenica dell’area costiera molisana. I risultati raggiunti, pur essendo, a nostro avviso, molto significativi, sono certamente ancora preliminari, ma rappresentano per l’area molisana un'importante base di partenza per gli studi che si occuperanno in futuro della tematica affrontata. Tali studi potranno consentire di sviluppare un quadro conoscitivo ed evolutivo più esteso, ma anche di maggiore dettaglio soprattutto in riferimento alle influenze climatiche, tenendo conto di dati acquisibili da altri settori costieri molisani e, in particolare anche delle evidenze morfo-sedimentarie dell'evoluzione medio e tardo-olocenica della costa molisana presenti in superficie. A multidisciplinary study comprising geomorphological, stratigraphical, paleontological, palynological and geochronological analyses has been carried out on sedimentary successions coming from two sectors of the Molise coastal area: the area of the Trigno river mouth and the area of the harbour of the Termoli city. The analyses were made on 6 core successions, three of which were drilled within the sea, some hundreds of meters from the current shoreline, in the area of the Trigno river mouth, and the other three on the beach, very near to the actual shoreline, in the area of the harbor of Termoli. The obtained results allowed us to reconstruct several stages of the palaeoenvironmental evolution of the study areas during Late Pleistocene and Holocene. The paleontological analyses were fundamental to reconstruct the palaeoenvironments in general, and to point out in particular several palaeo-bathymetric variations related alternatively to regressive and transgressive trends controlled by climatic changes occurred during the last 8000 years. In the area of the Trigno river mouth, during the Last Glacial Maximum, fluvial dynamics and erosion in particular gave origin to a very heterogeneous palaeo-topographical setting. After the Last Glacial Maximum (LGM), about 20000 years ago, fluvio-palustrine environments populated by non-marine fauna evolved and persisted for about 1000 years, giving way to a clayey-silty sedimentary sequence. At this time the sea level was about 100 m below the modern sea level and the shoreline located some tens of km more seawards. The next reconstructed evolutionary stage of this area is related to the progressive sea level rise and the Post-Glacial Holocene marine transgression. First, lagoonal-like, seaward open environments evolved. Successively, about 8000 years ago, marine, environments evolved, characterized by typical shoreface features and deposition of fossil-rich sands. These environments were populated by typical infalittoral fauna. In the first stage, the palaeo-bathymetries were very low and the sea level was about 11-12 m below the modern sea level. Immediately after, palaeo-bathymetries increased and the shoreline and related coastal-marginal environments moved further landward. Afterwards, the palaeo-bathymetries decreased again, allowing to identify a regressive trend most likely referring to the climatic cooling occurring about 6800-7000 years ago. At this period the sea level was at about 7,5/8,0 m below the present one. After the optimum climaticum, about 6000 years ago, the coastal and marine environments moved seaward and the palaeo-bathymetries decreased again, probably in response to a new phase of climatic cooling, tentatively related to the beginning of the Neoglaciation that started 5000-5500 years ago. The sea level during this period was about 4/5 m below the modern one. The next stage of environmental evolution is characterized by the persistence of littoral environments and various slight oscillations of the shoreline. At this period a fluvio-deltaic environment evolved giving way to phases of temporary emersion and consequent pedogenesis. The youngest portion of the examined sedimentary successions are related to the modern coastal setting, while sediment intervals referring to the Little Ice Age are lacking due to the consistent retreat (ca. 700 m) that has affected the coast line during the last century. The results obtained for the second study area, located immediately south to the harbour of Termoli are still preliminary and evidence a rather complicated and heterogeneous palaeoenvironmental evolutionary setting. The study allowed to identify various landward and seaward shifts of the shoreline during the Late Pleistocene and the Holocene giving rise to various stages of emersion during which the sediments partially underwent pedogenesis.. The arrival of the Holocene marine transgression in this study area corresponds to the period when sea level was about 11 m below the modern one. This evidence is in good agreement with the data obtained in the area of the Trigno mouth where the sea arrived near the present coast about 8000 years ago when the sea level was 11-12 m below the modern one. In the Termoli area several shoreline oscillations occurred before the Holocene marine transgression could be identified. At present it is not possible to precise the chronology of this oscillations which, however, took place certainly before the Last Glacial. The present study is the first one that deals specifically with the late Pleistocene and Holocene evolution of the Molise coast. The obtained results which are, we believe, very significant, are surely preliminary but may represent an important basis for further near-future studies on this thematic. Such studies, in fact, may contribute significantly to develop a more wider and detailed frame of knowledge also in relation to climate controls, taking in consideration sedimentary and morphologic data coming frorm other sectors of the Molise coast and, in particular, the outcropping morpho-sedimentary evidences which refer to the Middle and Late Holocene progradation of the Molise coast. Dottorato di ricerca in Ambiente e Territorio (XXIII ciclo)

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.