Giulio Pavia

Tectono-sedimentary evolution of the Pliocene to Lower Pleistocene succession of the Apricena-Lesina-Poggio Imperiale quarrying district (western Gargano, southern Italy)

The post-Miocene marine succession of the «Apricena horst» is described with the purpose to verify the chronostratigraphic constraints for the type-locality of the Pirro Nord Faunal Unit. The stratigraphic succession has been subdivided in four units bounded by ubiquitous unconformities with evidence of subaerial exposure. The two basal units (dated late Zanclean to at most early Piacenzian) are formally grouped in the Lago di Varano Fm. that on the whole consists of sediments ranging from lagoonal to circalittoral environments. Within the lowermost unit, a megabreccia is interpreted as the product of a tsunami event. The third unit, Gelasian in age, is informally cited as Calcari a Briozoi Fm. The last unit, the Lower Pleistocene Serracapriola Fm., consists of siliciclastic deltaic sediments and represents the closure of the marine cycle. Conspicuous lateral facies and thickness changes, and the frequency of unconformities are the consequence of an intense synsedimentary tectonic activity developed in the frame of the southern Apulia foredeep closure. In the study area, such activity is documented by two E-W trending normal faults which, during Zanclean and at least the earliest Gelasian, controlled the Pliocene horst-graben system of the Apricena-Poggio Imperiale area.

NEW EARLY BATHONIAN BIGOTITINAE AND ZIGZAGICERATINAE (AMMONOIDEA, MIDDLE JURASSIC)

Several tens of Lower Bathonian Bigotites from Digne-Castellane region (SE France) and Cabo Mondego area (Portugal) have been reviewed. Three species have been distinguished in the lowermost subzone of the Zigzag Zone (Parvum Subzone) just above the boundary Bajocian to Bathonian: B. diniensis Sturani [M+m], B. sturanii sp. nov. [M+m] and B. mondegoensis sp. nov. [M+m]. In the Bas Auran area, a chronocline from evolute, strongly ribbed and constricted forms (including B. sturanii and B. diniensis ) to involute forms with blunt, moderately prominent ribbing and weak constrictions (including B. mondegoensis ) can be recognized. The shared taxa B. mondegoensis sp. nov. and possibly B. diniensis Sturani permit detailed subdivision and correlation to be established between ammonite fossil assemblages of Parvum Subzone in the Lusitanian and Alpine basins. A separate genus of Zigzagiceratinae, Protozigzagiceras g. nov., is proposed to encompass P. torrensi (Sturani) as type species. These new palaeontological data about the youngest members of Bigotitinae and the oldest members of Zigzagiceratinae are of biochronostratigraphic importance for the subdivision and correlation of the basal Bathonian Zigzag Zone. Three successive biohorizons can be identified at the Parvum Subzone in Bas Auran (French Alpine Basin) and Cabo Mondego (Lusitanian Basin): Diniensis, Mondegoensis and Protozigzagiceras biohorizons.

Messinian rodents from Moncucco Torinese, NW Italy: palaeobiodiversity and biochronology

ABSTRACT The rodents from the Upper Messinian deposits of Moncucco Torinese (MCC) (Piedmont, NW Italy) are described. Stratigraphic considerations indicate that the fossiliferous deposits exposed at MCC date back to the post-evaporitic phase of the Messinian Salinity Crisis (5.40–5.33 Ma). Thirteen rodent taxa belonging to the families Cricetidae Fischer, 1817, Muridae Illiger, 1811, Gliridae Thomas, 1897 and Sciuridae Fischer, 1817 are recognized based on 1177 teeth. The occurrence of Centralomys benericettii (De Giuli, 1989), Paraethomys meini (Michaux, 1969) and Apodemus gudruna van de Weerd, 1976 allows to compare MCC with other latest Messinian localities of northern Italy, such as Brisighella and Verduno. The rodent assemblages described herein and, more particularly, the taxa A. gudrunae, Muscardinus vireti Hugueney & Mein, 1965 and Glirulus lissiensis Hugueney & Mein, 1965, suggest that MCC can be referred to the Late Turolian (MN13). Moreover, the presence of taxa commonly found in Pliocene localities of western and central Europe (Occitanomys brailloni Michaux, 1969, Micromys bendai van de Weerd, 1979, Neocricetodon magnus (Fahlbusch, 1969) and Sciurus warthae Sulimski, 1964) indicates that some typical Ruscinian elements were already present at the end of the Miocene at least in southern-central Europe. The rodent assemblages of MCC also include Apodemus atavus Heller, 1936, Eliomys aff. intermedius Friant, 1953, Glis minor Kowalski, 1956, and Pliopetaurista pliocaenica (Depéret, 1897). Overall, the fossil assemblages documented in this paper remarkably expand our knowledge on the Late Miocene rodent communities of Italy, also providing useful data for the interpretation of biogeographic relationships between western and eastern Europe at the end of the Messinian.

JURASSIC SEDIMENTARY AND TECTONIC PROCESSES AT MONTAGNA GRANDE (TRAPANESE DOMAIN, WESTERN SICILY, ITALY)

The Rosso Ammonitico of the Montagna Grande area is very interesting because of the great diversification in facies and thickness in three very closely situated sections. The Jurassic succession in this area is that typical of the Trapanese Domain. It starts with a thick pile of platform limestones (Inici Formation: Hettangian - Sinemurian) that are overlain by typically condensed and commonly nodular pelagic limestones (Rosso Ammonitico: Middle Jurassic - lowermost Cretaceous). The good exposure of this succession in active quarries allows observation of sedimentological and palaeontological details and to improve the understanding of the Jurassic tectono-sedimentary evolution. The Rocca chi Parra quarry shows a stepped surface, with a relief of some metres, incised in the Inici Formation. It is covered by lenticular or wedge-shaped lithosomes a few metres-thick of highly condensed Rosso Ammonitico. It is interpreted as a slide scar along which a thin but extensive block of lithified platform limestones was detached and slid downslope. The Poggio Roccione quarry shows neptunian sills and collapse structures in the middle part of the Rosso Ammonitico that on the whole is thicker (about 12 m) than at Rocca chi Parra. They indicate sea-floor instability probably due to seismic shocks with brittle to plastic behaviour of sediments depending on their coherence. The Montagna Grande outcrop shows an even thicker succession which includes a wedge of cherty limestones about 10 m thick intercalated between a lower and an upper Rosso Ammonitico calcareous unit. The features described in these three sections document a highly irregular sea-floor topography which in turn was controlled by several phases of extensional tectonics during Mid and Late Jurassic pelagic sedimentation. Structurally higher sectors closer to fault scarps were affected by a very condensed sedimentation, the opening of subvertical dykes and the triggering of large slides. Structurally lower sectors allowed preservation of thicker successions that were affected by gravitationally-induced soft to hard sediment deformation when tectonics resulted in an oversteepening of the slope.

Taphonomic Analysis of the Lower Pleistocene Pirro Nord Fossil Locality (Pirro 10 Site, Puglia, Southern Italy): A Depositional Model for Vertebrate Assemblages in a Karstic Environment

ABSTRACT Taphonomic analyses have been conducted on the macromammal remains found in Sedimentary Unit 7 of the lower Pleistocene Pirro 10 site of the Pirro Nord locality in Italy. Recent field research has concentrated on investigating the fossil content of this site and the genesis of the karst network and its related deposits. In the present study, we distinguish between preburial and synsedimentary (during burial) processes in order to group the vertebrate remains into different taphonomic categories according to their various states of preservation, thus introducing the concept of taphorecord—borrowed from invertebrate taphonomy—into macrovertebrate taphonomy for the first time. Element quantification, evaluation of transport effects, and state of preservation of the skeletal elements were studied and all elements separated into four taphorecords according to their relative chronology. The use of taphorecords also improves the accuracy of the data obtained from the various methods of element quantification. The analysis of bone sorting and orientation indicates that the fossiliferous deposits originated by water flows carrying both fossils and sediments, alternating with phases of carcass accumulation and reelaboration of bones from previously deposited layers. The study presented here serves as a proof of concept for the use of taphorecords in analyses of fossiliferous deposits in caves.

Two Examples of the Geoheritage Potential of Piedmont (NW Italy): Verrua Savoia for the Present, Valle Ceppi for the Future

The aim of this article is to describe two “model” geosites of Torino province (Piedmont, NW Italy) in order to explain the state of the art of paleontological and stratigraphical geosite inventory and management in Piedmont. Collaboration between Torino University, local administrations, and industry resulted in the inauguration of the first geosite in Torino province, located in Verrua Savoia quarry, in October 2010. This site documents the geological record of the birth, life and death of a submerged mud volcano. Based on the success of this project, we propose the creation of another equipped area in Valle Ceppi, which constitutes an international point of reference for the study of Miocene molluscs. Piedmont is a region characterized by a heterogeneous patchwork of geological peculiarities that need to become public knowledge. Mismanagement of these areas may lead to their destruction, resulting in irreparable scientific and cultural damage. It should also be noted that the creation of equipped geosites plays an important role in the development of environmental awareness among the general public and local administrative entities and also increases the economic resources of the surrounding areas.

INTEGRATED STRATIGRAPHY FROM THE CONTRADA FORNAZZO SECTION, MONTE INICI, WESTERN SICILY, ITALY: PROPOSED G.S.S.P. FOR THE BASAL BOUNDARY OF THE TITHONIAN STAGE

This paper deals with a definition of the lower boundary stratotype of the Tithonian Stage in the Upper Jurassic succession of Monte Inici, Western Sicily. The upper member of the Rosso Ammonitico Fm. is 27 m thick and shows a typical nodular-calcareous lithofacies; its lower beds have been sampled for biostratigraphic and paleomagnetic purposes. Though the succession is affected by high stratigraphic condensation, the resulting hiatuses have been shown to be below biochronological resolution and thus do not hinder any biostratigraphic definition. The biostratigraphic analysis has been based on the rich ammonite assemblages in which the common genus Hybonoticeras is the index-key for characterizing the Kimmeridgian-Tithonian boundary. Four ammonite biozones have been identified; the basal Tithonian one is defined by the assemblage of Hybonoticeras gr. hybonotum and Haploceras staszycii . The recorded calcareous nannofossil bioevents allow recognition of the V. stradneri and C. mexicana Zones, whose boundary is located a little below the identified Tithonian lower boundary. The paleomagnetic record shows normal polarity in the S. darwini/V. albertinum Zone and mainly reverse polarity in the H. beckeri and H. hybonotum Zones, with three minor normal polarity intervals; the lower boundary of the Tithonian falls in the oldest of these intervals. The integrated multidisciplinary stratigraphic information gathered from the Contrada Fornazzo section defines the lower boundary of the H. hybonotum Zone at the base of Bed 110, and supplies elements of chrono-correlation sufficient to regard this section as a possible G.S.S.P. of the Tithonian Stage.

LOWER TO MIDDLE MIOCENE MOLLUSC ASSEMBLAGES FROM THE TORINO HILLS (NW ITALY): SYNTHESIS OF NEW DATA AND CHRONOSTRATIGRAPHICAL ARRANGEMENT

The goal of this study is to correlate in chronostratigraphic order the fossil assemblages of selected, historical Lower and Middle Miocene localities of the Torino Hills. More than 18,000 specimens have been classified and assigned to 798 taxa (cf. Tab. I). The compositional analyses mainly concern the 672 listed gastropods, most of which were already described in classical monographies. The critical evaluation of the morphological and architectural shell parameters let to a significant reduction of the species that could be realistically maintained in comparison to those cited in literature from the Torino Hills Miocene. Six localities have been analyzed: Valle Ceppi (VC) and Val Sanfra (VS) referred to the middle part of the Burdigalian stage (N7a Biozone), Villa Bertini at the topmost Burdigalian, Villa Allason (VA) and Villa Forzano (VF) at the early Langhian (N8 Biozone) and Monte dei Cappuccini (MC) at the late Langhian (N9 Biozone). On the whole, the fossil assemblages show a taxonomic variation of both biochronologic and palaeobiogeographic meaning. Actually, the similarity in specific biodiversity of VC, VS, VB, VA and VS reflects homogeneity among late Burdigalian to early Langhian palaeocommunities. As to MC, its deep difference on VC is correlatable with the eastern closing between the Mediterranean areas and the Tethyan Realm, at the boundary Burdigalian-Langhian, that brought to disjoint evolutions of the Mediterranean and Indo-Pacific palaeocommunities, the former being influenced by oceanic current changes and related climatic variations.