ALLOSTRATIGRAPHY AND SEISMIC STRATIGRAPHY OF THE MIOCENE SEDIMENTS OF THE SPICCHIAIOLA - POMARANCE AREA, SOUTHERN SIDE OF THE VOLTERRA BASIN (TUSCANY, ITALY)

The objective of this work is to analyze the Miocene depositional units of the southern side of the Volterra Basin (Tuscany, Italy) utilizing outcrop and seismic data and to establish the major events that led to their formation. Four depositional units have been recognized: Unit 1 is characterized by marine sediments of late Serravallian-early Tortonian age; Unit 2 is characterized by fluvio-lacustrine and brackish deposits of late Tortonian-early Messinian age; Unit 3 is characterized by marine deposits of early Messinian age; Unit 4 is characterized by the lacustrine deposits ("Lago-mare" facies) of late Messinian age. The deposition of these four units is associated with an extensional tectonic regime that has been active in Tuscany since the late Tortonian. This regime generated half graben type structures in which deposition occurred. The recognized unconformities between the units are mainly related to uplift as a consequence of the extensional tectonic regime.   &nbsp

CALCAREOUS PLANKTON HIGH RESOLUTION BIOSTRATIGRAPHY (FORAMINIFERA AND NANNOFOSSILS) OF THE UPPERMOST LANGHIAN – LOWER SERRAVALLIANRAS IL-PELLEGRIN SECTION (MALTA)

Results of an integrated biostratigraphic (calcareous nannofossils and planktonic foraminifers) study of the uppermost Langhian/lower Serravallian Ras il-Pellegrin section (Fomm ir-Rih Bay – Malta) are presented. This high resolution study allowed us to recognise several useful lower Serravallian bio-events in the Mediterranean and to provide a detailed distribution pattern of the recognised taxa. The astrochronological calibration, reported in a different paper of this volume, provided absolute ages of the bio-events of the studied section. The LO (Last Occurrence) of Globorotalia peripheroronda at 13.39 Ma, the Paragloborotalia partimlabiata FO (First Occurrence) at 12.62 Ma and the Paragloborotalia mayeri FCO (First Common Occurrence) at 12.34 Ma among the planktonic foraminifera, and the Sphenolithus heteromorphus LO at 13.59 Ma, the Cyclicargolithus floridanus LCO (Last Common Occurrence) at 13.39 Ma, the Reticulofenestra pseudoumbilicus FCO at 13.32 Ma, the Calcidiscus macintyrei FO at 12.57 Ma and the Calcidiscus premacintyrei LCO at 12.51 Ma among the calcareous nannofossils, were recorded. Moreover, our results confirm the LO of S. heteromorphus as a fairly synchronous event in the Mediterranean and in the Atlantic and Pacific Oceans. Therefore, we suggest a lithological level near or coincident with this event for the definition of the GSSP of the Serravallian. The Ras il-Pellegrin section may be considered a good candidate for this definition.&nbsp

CALCAREOUS PLANKTON BIO-EVENTS IN THE MIOCENECASE PELACANI SECTION (SOUTH-EASTERN SICILY, ITALY)

The upper Serravallian-Lower Tortonian Case Pelacani section in Sicily is represented by the epipelagic sediments of the Tellaro Formation. Along the section, which was sampled in four easily correlatable segments, a more or less continuous sequence of lithologic couplets, with whitish marls and blackish levels in the lower part and whitish marls and whitish more indurated levels in the upper part are present. The distribution of the most common taxa of planktonic foraminifera and calcareous nannofossils was quantitatively estimated in 316 samples, collected every 20 cm along the section which is 66.35 m thick. This allowed to identify eleven planktonic foraminifera (but only the eight marker events were quantitatively estimated) and five calcareous nannofossil bio-events.  Their astrochronology is reported by correlation with the cyclostratigraphic results obtained for this section in a different paper. The ages are well comparable with the ages published for the same events in other Mediterranean sections. Paleomagnetic analysis along 30 meters in the central part of the section gave puzzling results and therefore no reliable magnetostratigraphy could be obtained. The Case Pelacani section, straddling the stratigraphic interval between slightly below the first occurrence and slightly above the first regular occurrence of Neogloboquadrina acostaensis , is a good candidate for the definition of the GSSP (Global Stratigraphic Section and Point) of the Tortonian. Independently from the selected section, we suggest to define the Serravallian/Tortonian boundary in a level coincident or near the last occurrence of Paragloborotalia siakensis, as already proposed, or coincident with or near the last common occurrence of Globigerinoides subquadratus. This latter level virtually coincides with the first common occurrence of Globigerinoides obliquus obliquus and is slightly above the last common occurrence of Discoaster kugleri, which occurs only 2.25 meters (and 3 precessional cycles) below in the studied section.&nbsp

The "Brunella" project: preparation and study of a mysticete from the Early Pliocene of Tuscany

• A project is being carried out at Poggio alle Mura that will allow the preparation and study of a balaenopterid whale from the early Pliocene of Tuscany together with its associated biota. • Up to now, the project resulted in the preparation of 18 vertebrae, the skull and an ulna of the whale. • The associated biota includes 18 mollusk species, 2 sea urchin species, 10 shark teeth and thousands of fish remains from the sediment surrounding the skull. • A wealth of educational activities is being carried out at the laboratory of Poggio alle Mura that are directed to schools and citizens

ASTROCHRONOLOGICAL CALIBRATION OF THE UPPER SERRAVALLIAN/LOWER TORTONIAN SEDIMENTARY SEQUENCE AT TREMITI ISLANDS(ADRIATIC SEA, SOUTHERN ITALY)

A high resolution cyclostratigraphic study was carried out on a cyclicaly bedded succession of late Middle Miocene deep marine deposits from the Tremiti Islands, Adriatic sea (Italy). Astronomical calibration of the sedimentary cycles provides absolute ages for different calcareous plankton bioevents, widely used for intra Mediterranean correlation, in the interval between 11.12 and 12.60 Ma. The sedimentary record of the S. nicola composite section consists of an alternation of indurated, withish coloured, CaCo3 rich and grey less indurated, CaCo3 poor marly beds, at times replaced by red coloured CaCo3 poor marls. Results of direct correlation between the La 90 (1,1) solution of the insolation curve and the cyclic lithologic patterns occurring in the studied sections, combined with results of spectral methodologies applied on the climate sensitive data (CaCo3 and Globigerinoides) showed that the classic Milankovitch periodicity can be represented through the modulation forcing of the studied sedimentary records.&nbsp

AN INTEGRATED CALCAREOUS PLANKTON BIOSTRATIGRAPHIC SCHEME AND BIOCHRONOLOGY FOR THE MEDITERRANEAN MIDDLE MIOCENE

The relative position of 30 main bioevents  pertaining to calcareous nannofossils and planktonic foraminifera was identified in the time interval between 13.75 Ma and 10.50 Ma, based on the quantitative study of the those microfossils in three Mediterranean sections spanning the late Langhian – lower Tortonian stratigraphic interval. The events were correlated  to the astronomic target curve using a cyclostratigraphic approach, resulting in a very detailed biostratigraphic and biochronologic subdivision of the interval. The zonal scheme proposed by Fornaciari et al. (1996) was adopted for the calcareous nannofossils, but three subzones were identified in the MMN7 Zone. For the planktonic foraminifera reference is made to the zonal scheme recently proposed by Foresi et al. (1998), slightly modified in order to increase its biostratigraphic resolution. The age of all the zonal boundaries is reported.&nbsp

Backdating systematic shell ornament making in Europe to 45,000 years ago.

Personal ornaments are commonly linked to the emergence of symbolic behavior. Although their presence in Africa dates back to the Middle Stone Age, evidence of ornament manufacturing in Eurasia are sporadically observed in Middle Palaeolithic contexts, and until now, large-scale diffusion has been well documented only since the Upper Palaeolithic. Nevertheless, little is known during the period between ca. 50,000 and 40,000 years ago (ka), when modern humans colonized Eurasia replacing existing hominin populations such as the Neandertals, and a variety of “transitional” and/or early Upper Palaeolithic cultures emerged. Here, we present shell ornaments from the Uluzzian site of Grotta del Cavallo in Italy, southern Europe. Our results show evidence of a local production of shell beads for ornamental purposes as well as a trend toward higher homogeneity in tusk bead shape and size over time. The temporal interval of the layers of interest (45–40 ka) makes Cavallo the earliest known shell ornament making context in Europe

Pianosa: mareggiate di ieri e di oggi

Ma te la ricordi quella libecciata ? Ognuno ha il suo vento preferito; o meglio, vive lungo una costa esposta ad un determinato vento e, in qualche modo, vi si affeziona, lo aspetta. Ogni volta che si realizza una giornata burrascosa, gli abitanti della costa snocciolano la saga dei ricordi. I più anziani scendono nel passato più remoto, dando una tale enfasi all'accaduto da farlo diventare leggendario. In questi casi il tempo trascorso esalta il ricordo e rende gli eventi più grandi e drammatici di quanto non lo siano stati veramente. Ma ciò non deve sminuire la realtà. Gli eventi eccezionali esistono, non sono molti, è vero, e non siamo sempre presenti ad assistervi. Ma alcune combinazioni particolari nella direzione del vento, nella sua durata e intensità, nel fetch (con questo termine viene indicato un tratto di mare, reale o potenziale su cui un vento insiste o può insistere), in alcuni casi convergono a generare un evento straordinario. Allora onde inusuali, con frequenza inaspettata, cominciano a frangere sulle coste sommergendole e imbiancandole di schiuma, anche in tratti che avremmo pensato raggiungibili solo dagli spruzzi

I Foraminiferi: incredibile fonte di informazioni sul passato e sul presente del nostro pianeta

I Foraminiferi Sono organismi molto semplici, ma straordinariamente affascinanti, che appartengono alla classe dei Foraminiferi, regno dei Protisti. Nonostante la ricchissima letteratura che li riguarda, di tipo sia biologico che paleontologico, ancora oggi presentano aspetti non completamente conosciuti. Nel testo si offre una rassegna di alcune particolarità di questi organismi e dell'utilità della loro conoscenza

Pianosa – Nascita di un’isola. Diciannove milioni di anni di storia geologica. Dalle prime rocce alla migrazione dei cervi nell’ultimo periodo glaciale

Premessa alla Guida a cura di Franca Zanichelli e Luca Maria Foresi: A Cala di Biagio, nel buio di una caverna che si apre sul mare alcuni studiosi hanno raccolto resti di faune che hanno popolato quelle terre che oggi chiamiamo isola di Pianosa. Già nella seconda metà dell’Ottocento l’archeologo don Gaetano Chierici, il fondatore della paletnologia in Italia, scavò in quello stesso anfratto con l’intento di raccogliere indizi delle antiche presenze umane concentrandosi su affioramenti che restituirono significativi elementi dell’Età del Bronzo. Rimase intatto un importante giacimento, di età precedente, che oggi ci ha restituito reperti fossili di mammiferi, 3 crani di cervi mostrati al pubblico per la prima volta in questa esposizione e altre ossa di faune minori, tuttora in studio. Nelle parti della grotta, sollevando lo sguardo verso l’alto sono peraltro visibili i tondi fori di litodomi, inequivocabile indizio della dissoluzione chimica provocata da organismi marini, per cui di una fase in cui il livello del mare era più alto di quello attuale. Questa breve narrazione ci fa riflettere su alcune questioni. La grotta è solo a pochi metri sul mare e questo non sarebbe stato davvero un luogo sicuro per i nostri antenati, forti e intraprendenti, ma poco attrezzati. Quindi è probabile che il livello dell’acqua fosse più in basso di quello attuale e probabilmente l’anfratto doveva essere un riparo in quota. Se poi c’erano stati in giro ungulati grande taglia come i cervi che pascolano nelle foreste, dovevano esservi spazi ampi per avere sufficiente nutrimento, in definitiva non poteva non esservi un collegamento più o meno ampio con la terraferma. La mostra perciò si intitola la nascita di un’isola e l’esposizione didattica ne racconta l’origine geologica e gli eventi desumibili dai resti fossili e dalle rocce. Sotto la guida degli esperti quegli ammassi di gusci più o meno pietrificati si animano e ci consentono di leggere le vicende geologiche che hanno portato alla formazione dell’isola, al susseguirsi di eventi tettonici e bioclimatici che hanno segnato profondamente la storia iniziale