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This paper deals with the stratigraphy of well SPAN 1 (San Pietro al Natisone, Eastern Friuli). The stratigraphic sequence is composed by Paleocenic flysch deposits (from 69 m to 748 m), Maastrichtian resedimented carbonates (from 748 m to 940 m) and Late Jurassic reef deposits (from 940 m to 1397 m, total depth). The tectonic and sedimentary evolution of the Valle del Natisone, from the Oxfordian to the Early Eocene, is outlined.

The Adriatic Carbonate Platform (AdCP), which is one of the largest carbonate platforms during Mesosoic Era of the Perimediterranean region, also comprise a major part of the entire carbonate succession of the Croatian Karst (External or Outer) Dinarides, thick in some places more than 8000 m, and chronostratigraphically ranges from the Middle Permian (or even Late Carboniferous) to the Eocene (VLAHOVIĆ et al., 2005). During the Late Cretaceous the AdCP was characterized generally by shallow-water peritidal depositional conditions, interrupted by two drowned platform events (MORO et al., 2002 ; VLAHOVIĆ et al., 2005). Rudists which throve in such paleoenvironments were elevators, sediment dwelling radiolitids. They are preserved mostly as in situ toppled congregations (ROSS & SKELTON, 1993) which ranges from the smallest bouquets towards cluster and finally the biggest thicket forms within laterally present biostromes representing floatstones to rudstones. Besides this most common appearance in the form of biostromes, in the Cenomanian of Istria at the Premantura locality, radiolitid–chondrodont congregations appear as mound and lensoidal forms.

Beside biostromes which are the most common paleoenviromental appearance of rudist congregations, in Upper Cretaceous of Istria rare rudist mud-mounds were investigated. Aim of this work is to present appearance of rudist congregations with respect to the lithofaces characteristics of paleoenvironment. Rudist congregations, which could appear within both mud mounds and biostromes in relatively shallow subtidal are result of interaction between accommodation space adequate for thriving of radiolitids and carbonate sedimentation rate. Shallowing and decrease of accommodation space are indicated in mud mounds by thin sheets of densely packed F-R with fragments of radiolitids at the top of beds, together with mud mound flanks which are visible as lamination. In case when radiolitid congregations throve in shallower subtidal paleoenvironment with less accommodation space they appear through biostromes.

Il progetto RoofOfRock, finanziato nell’ambito del 2° bando di cooperazione transfrontaliera dell’Adriatico IPA 2007-2013 è iniziato nell’ottobre 2012, si concluderà a fine settembre del 2015 e coinvolge 10 partner di 4 nazioni: Slovenia, Italia, Croazia e Bosnia Herzegovina. In qualità di partner associato e stakeholder partecipano le regioni Friuli Venezia Giulia e Veneto. Il progetto RoofOfRock ha tra le sue finalità quelle di proporre un utilizzo del calcare tabulare compatibile con l’ambiente, di favorirne la protezione e la promozione nonché di elaborare delle linee guida utili per una sua valorizzazione come patrimonio naturale e culturale. I principali obiettivi del progetto sono i seguenti: studiare l’utilizzo dei calcari tabulari lungo il settore carsico dell’Adriatico nel corso della storia e individuare gli esempi di buona e di cattiva prassi; determinare le principali proprietà fisico-meccaniche dei calcari tabulari che vengono adoperati come materiale da costruzione; individuare le aree estrattive del calcare tabulare utilizzato negli edifici selezionati ed analizzare dal punto di vista geologico, geomorfologico e paleontologico gli affioramenti presenti all’interno delle zone di provenienza; individuare delle aree di provenienza del calcare tabulare dove si possano attuare tecniche di estrazione compatibili con l’ambiente; definire un quadro legislativo comune su tutto il territorio interessato dal progetto; rendere consapevoli ed istruire gli stakeholder (progettisti, architetti, costruttori edili, ecologisti, soprintendenti regionali, rappresentanti delle autorità locali), gli utilizzatori (artigiani) nonché in generale l’opinione pubblica, sulla corretta prassi di utilizzo della pietra da costruzione, sull’uso sostenibile delle risorse minerarie, e sul mantenimento dei beni naturali e del patrimonio culturale. La Regione Adriatica condivide la storia geologica, specie quella degli ultimi 200 milioni di anni. I platy limestone (calcari tabulari) giurassici, cretacici e paleocenici sono stati ampiamente utilizzati come materiale da costruzione in tutta l’area e rappresentano un importante elemento comune ai popoli adriatici. L’utilizzo di pietre calcaree come materiale da costruzione tradizionale è proseguito sino ai giorni nostri dando un’impronta particolare al paesaggio della costa adriatica. In questo volume vengono descritte le caratteristiche litologiche e le modalità estrattive dei calcari tabulari. Vengono inoltre presentati gli studi condotti su 10 edifici, religiosi e civili, tipici dell’area carsica (5 per l’Italia e 5 per la Slovenia) che presentano elementi architettonici in calcare tabulare. Pri projektu RoofOfRock, ki je bil izbran za sofinanciranje v okviru 2. poziva Jadranskega čezmejnega programa IPA 2007–2013, sodeluje deset projektnih partnerjev iz štirih držav, in sicer iz Slovenije, Italije, s Hrvaške ter iz Bosne in Hercegovine. Projekt se je začel izvajati oktobra 2012 in se bo zaključil konec septembra 2015. Pri projektu sodelujeta tudi italijanski pokrajini Furlanija - Julijska krajina kot deležnik in Benečija kot pridruženi partner. Namen projekta RoofOfRock je vzpostaviti skupni temelj za trajnostno rabo, zaščito in promocijo ploščastih apnencev ter oblikovati uporabne smernice za trajnostno upravljanje ploščastih apnencev kot skupne naravne in kulturne vrednote na celotnem projektnem prostoru. Poglavitni cilji projekta so: analizirati uporabo gradbenega kamna na kraški jadranski obali skozi zgodovino in prepoznati primere dobre in slabe prakse; opredeliti osnovne naravne značilnosti apnencev, ki se uporabljajo kot gradbeni material, ter natančno opredeliti naravne značilnosti in pojavljanje ploščastih apnencev; opredeliti izvor gradbenega kamna, uporabljenega v izbranih objektih, in raziskati pojavljanje teh kamnin v naravi; opredeliti naravna nahajališča ploščastih apnencev in analizirati pogoje za trajnostno rabo te mineralne surovine; pripraviti strokovno podlago za skupni zakonodajni okvir na celotnem projektnem območju; ozavestiti in izobraziti deležnike (prostorski načrtovalci, arhitekti, gradbeniki, naravovarstveniki, konservatorji, predstavniki lokalnih in državnih oblasti), uporabnike (obrtniki) in širšo javnost o dobri praksi uporabe gradbenega kamna, trajnostni rabi mineralnih surovin ter ohranjanju naravnih vrednot in kulturne dediščine na primeru ploščastih apnencev. Območje Jadrana deli skupno geološko preteklost, dolgo najmanj 200 milijonov let. Apnenec, nastal na plitvi karbonatni platformi, so na celotnem projektnem območju uporabljali kot glavni gradbeni material in ima eno najpomembnejših vlog pri oblikovanju skupne zgodovine. Uporaba ploščastega apnenca kot tradicionalnega gradbenega materiala se je ohranila do današnjih dni in jadranski obali daje poseben pečat. V pričujočem delu so opisani litološke značilnosti in načini pridobivanja ploščastega apnenca ter uporaba tega materiala pri gradnji desetih značilnih sakralnih in posvetnih stavb z območja matičnega Krasa (petih iz Italije in petih iz Slovenije), v katerih so zastopani arhitekturni elementi iz tovrstnega kamna. The RoofOfRock Project is being implemented under 2nd call for ordinary projects of Adriatic IPA CBC Programme 2007, joining 10 partners from 4 countries Slovenia, Italy, Croatia and Bosnia and Herzegovina. It started in October 2012 and is going to be implemented until the end of September 2015. Two Italian Regions Friuli Venezia Giulia and Veneto are participating as stakeholder and associate partner . The RoofOfRock intention is to establish joint platform for platy limestone sustainable use, preservation and promotion, to create the relevant guidelines and to upgrade both individual and joint capacities in preserving such common natural and cultural heritage. The specific objectives of the project are: To analyze the use of building stone in Adriatic karst through time and to identify examples of best and bad practice; To define general natural characteristics of limestone used as building material dimension stone and to characterize precisely the natural characteristics and extent of natural appearance for the specific platy limestone; To identify provenience of stone used in architecture and to analyze the spatial distribution of the specific rock types in nature; To identify remaining natural resources and analyze conditions for sustainable use of this mineral commodity and to prepare grounds for common legislation in the project area; To prepare grounds for common legislation in the project area; To educate the stakeholders (spatial planners conservators, and local government), craftsmen and general public in best practice use of building stone in project area and to promote the sustainable use, preservation of cultural heritage and natural heritage. The entire Adriatic Region shares at least 200 million years of common geological history. The limestone formed on this platform was used as a primary building material throughout the whole project area and takes one of the most important roles in creating common human history. The specific platy limestone as the basic construction material gives the Adriatic coastline and its hinterland the primary character. In this booklet, the lithological characteristics and the exploitation techniques for platy limestones are described. Moreover, the traditional use of this building material is presented through 10 typical civil or religious buildings from Classical Karst area, 5 from Italy and 5 from Slovenia, where architectural elements made of platy limestone are present.

The Paleogene carbonate megabreccias of the Eastern Friuli, South-Eastern Alps of Italy, are thick, up to 260 m, and laterally extensive, up to 100 km, bodies attributed to catastrophic submarine landslides, which occurred in a deep-water, turbidite-filled foredeep basin (Julian Basin or Slovenian Basin of the Slovene geologists). The Grivo Flysch succession (late Paleocene-early Eocene) contains several of these mass-transport deposits (MTD) intercalated within carbonate, siliciclastic and mixed turbidites. Megabreccias are mainly composed by shallow-marine detritus from the Friuli Carbonate Platform. The latter, placed at the southern boundary of the basin, was a passive, distal margin at the time of deposition of these units, far from the deformational front of the Southern Alps. The type and the scale of the processes interred for the largest MTDs, as well as the size of the individual component slide blocks (olistoliths), are comparable with the well-studied Eocene carbonate megabreccias of the Southern Pyrenean Foreland Basin. Notwithstanding such impressive characteristics, the MTDs of the Julian Basin have attracted the attention of a limited number of researchers with only few local scientific productions, not easily available to the international community. Therefore, these bodies are still relatively poorly understood especially in terms of sedimentary processes and emplacement mechanism. Previous studies mainly addressed the litostratigraphy of the Julian Basin succession and the sedimentological characteristics of the internal organization of the MTDs. Other aspects such as the number and the ages of these bodies, thicknesses and variation of internal divisions, the provenance of the material and the triggering mechanisms have been also considered. On the other hand, many crucial issues concerning the Julian Basin MTDs have not been discussed or remain unsolved, especially in light of a modern approach that takes into account the recent progressions in marine geology regarding large-scale mass transport deposits. In particular, detailed studies on the internal kinematics and the down-slope evolution of the mass-transport have not been performed systematically, although the excellent and continuous exposures and the high basin-wide correlation potential of each bed, due to the lack of intense tectonic deformation. This favorable context allows studies on the relationships between the transport-emplacement of the MTDs and the deformation of the substratum, which have not been investigated so far. Our communication addresses these aspects, as well as the overall distribution, architecture and physiographic setting of these deposits in the framework of the Julian Basin. A general synthesis of the emplacement mechanism of the largest of these beds (ie. Vernasso unit or MB 11) will be advanced, in comparison with other fossil examples known in the literature.

Gornjokredne rudistne litosome istaložene unutar plitkovodnih okoliša u području južne Istre (Skokovac, Kažela i Premantura) obilježene su različitim lateralnim i vertikalnim litofacijesnim značajkama rudistnih zajednica. Litofacijesi istraživanih profila obilježeni su raznim litotipovima vapnenca s muljnom do sparitnom potporom, a sadrže plitkomorsku foraminifersku zajednicu s aglutiniranim i porculanastim stjenkama. Rudisti su zastupljeni s radiolitidnim vrstama koje su obitavale u podplimskom okolišu unutar različitih tipova zajednica, u rasponu od nekoliko desetaka do nekoliko stotina jedinki. Otvorenost izdanaka omogućuje dvo- i trodimenzionalni pristup rekonstrukciji građe rudistnih litosoma i facijesa. Rudistne zajednice sastoje se od gusto pakiranih jedinki u položaju rasta koje lateralno prelaze u floutstone s polegnutim i bioerozijom fragmentiranim ljušturama. Taložni okoliš rudistnih facijesa predstavlja prijelaz iz plitkog podplimskog okoliša do relativno otvorenog okoliša prema zaštićenom, gdje promjena itofacijesnih značajki rudistnih zajednica ovisi o međusobnom odnosu bioprodukcije i sedimentacije.

The lithological and faunal succession cropping out close to the famous palaeontological locality of Bacevica (Eastern Serbia) is described along a very discontinuous and ill-exposed section. Since the section is dominated by clastic sediments, no-vestige of the so-called 'Vrbovac reef' has been observed. Rhythms consisting of a limestone breccia lower unit and a fossil-rich upper part characterize the base of the section while rare silt and sand-rich limestone breccias and prevailing silty/sandy soils are the lithologies observed in the upper part of the same. The faunal succession shows an alternation of monospecific-paucispecific assemblages and much more diverse assemblages of rudists. The stratigraphic distribution of the different examples of rudist bivalves recovered at Bacevica may represent a significant tool for biostratigraphic correlations as far as the late Campanian deposits in the Central Tethys area are concerned. In particular, the Pseudopolyconites-bearing strata seem to be included within a few fossiliferous lithosomes. Therein the Serbian rudistologists instituted twenty species of Pseudopolyconites on the base of the characteristics of their ligamental ridge. Biometrical analyses have been made on the transverse sections of the right valves of the Pseudopolyconites holotypes illustrated in the scientific literature. It is suggested that the wide variability of the ligamental ridge shape alone does not warrant the institution of so many species of the genus in question but the existing ones should probably be re-considered as simple eco-morphotypes.

The new locality with dinosaur footprints has been discovered in the port of Karigador village in Istria. The site is situated in peritidal limestones of late Cenomanian age. The track-bearing horizon is bioclastic wackestone-packstone deposited in a subtidal environment. A single trackway which consist of 28 pairs of footprints and a group of 4 track pairs was registered at the site. Trackways belong to quadrupedal dinosaurs and are assigned to sauropods. Oval-circular shaped footprints represent the pedal prints and horseshoe-semicircular shaped ones represent the manus prints. The trackway is of narrow-gauge type with outwardly rotated manus and pedal prints. The average length of the pedal prints is 33 cm what indicates the length of the individual of app. 10 m. The preferred gait of the individual was a normal walk, taking normal strides with a speed of around 3 km/h. The trackmaker was a non-titanosaurian sauropod. Together with the other late Cenomanian sauropod localities in Istria (Fenoliga and Ladin Gaj), the Karigador site represents an example of sauropod tracks in a carbonate platform environment which can be assigned to Brontopodus ichnofacies., Rivista italiana di Paleontologia e Stratigrafia, Vol 112, No 3

The renewed deposition in the Paleogene and the oldest part of the non-interrupted Paleocene succession is characterized by presence of Decastronema barattoloi (De CASTRO), cyanobacterial tubes originally described in the Apennines. The reinterpretation of limestones from several sections located in the Kras region (NW part of the AdCP: Basovizza, Dolenja vas, Sopada, Čebulovica) confirmed the presence of these microfossils in peritidal sediments of Danian age (SBZ 1). The Cuisian (Late Lower Eocene) sediments, from eastern Istria (Brnjci section), Cres Island (Koromačna Cove section) and Ravni kotari (Benkovac - Korlat section) contain, in great numbers, individuals of this species. The cyanobacterial tubes are scattered in laminated, fine grained mudstones and wackestones, immediately above the Cretaceous sediments (occasionally above bauxites or breccias). The Decastronema-bearing sediments pass upward into the Foraminiferal limestones of Cuisian age (SBZ 11, based on conical agglutinated foraminifera and alveolinids), allowing age attribution of the cyanobacteria remnants. The Paleocene specimens are minute (up to about 180 μ m), thick walled tubes that occur with the index fossil Bangiana hanseni DROBNE. The Eocene forms accompanied by ostracods, pelecypods, and miliolid and rotaliid foraminifera are segmented tubes, up to 400 μ m long and usually thin walled.

Since last year few informations were disposable about the dinosaurs which lived on the Periadriatic Carbonate platforms during the Cretaceus. The general believing was that platforms were above all restricted shoals, lagoons, peritidal to supratidal environments which could have not substained large terrestrial animals.

The Istrian flysch deposits are connected with the Pyrenean tectonic phase. They accumulated in a narrow shortliving deep-sea trough from the Lutetian in the northwest and from the Late Eocene in the southeast. This polarity is connected with feeding of the trough from the north west. The flysch deposits pass into underlying hemipelagic marls, or gravity flow deposits, which overlay a carbonate platform. Locally, they overlay discordantly the carbonate platform. The flysch deposits are about 300-350m thick and dominated by thin- and medium-bedded turbidites in the lower and middle parts, and by medium- thick- bedded turbidites in the upper part. The thick-bedded turbidites are connected with a regressive phase. The underlying hemipelagic marls are totally bioturbated and comprise low diverse trace-fossil assemblage that resembles the Zoophycos-Cruziana transitional ichnofacies. The flysch deposits are only partially bioturbated and comprise very diverse trace-fossil assemblage with numerous K-selected predepositional forms, including diverse graphoglyptids. The assemblage is compared to the Nereites ichnofacies and indicates ecologically stable, well-oxygenated, moderately oligotrophic environment between turbidite deposition, typical of the Eocena flysch deposits in the Carpatians, Alps, and probably in the other areas.

Sedimentary and stratigraphic developments with tectonic settings of Paleogene and Neogene sediments in individual Central Europe basins.

The planning of civil engineering infrastructures and the exploitation of mineral resources in lithologically and structurally heterogeneous carbonate-dominated rock assemblages should take into account associated complex karst structures as potential geohazards. A recent study on the Paleocene-Eocene sedimentary succession outstandingly exposed in the Anhovo quarry (Outer NW Dinarides, Slovenia) points out the occurrence of paleokarst structures that are the result of localised dissolution processes along phreatic channels. These fluid flow pathways follow the directional anisotropy provided by a complex network of lithological matrix/clasts contacts in a matrix-rich depositional unit of ancient, large-scale submarine landslides (mass transport deposits; MTDs), which is in turn originated by specific sedimentary and post-sedimentary processes. Among primary sedimentary processes, down-slope gravitational transport favoured the lithological disaggregation and mixing of slide blocks and clasts into a marly-silty matrix, which later played an important role in controlling subsequent diagenetic processes on such exhumed MTDs. In this framework, groundwater flow followed different lithological and structural contacts, and block/clast boundaries, allowing the formation of contact karst structures, consequently providing favourable conditions for the formation of geomechanical labile systems in heterogeneous lithological units. The complex “worm-like” network of such phreatic channels, with certain anatomical features defined by the shape and orientation of structures and slide block/clast contacts, represents a zone potentially prone to gravitational collapse. The presented results suggest that the correct interpretation of synsedimentary structures, backed up by e.g. georeferencing of the contacts and the orientation of the slide blocks axes, allows us to identify or predict potential geomechanically weak areas of the quarry slopes where landslides could well be activated, and thereby contributes to better, more efficient decision-making on issues related tosafe mining and/or civil engineering practices.

The Paleogene carbonate “megabreccia” units of the Friuli Basin are composite deposits produced by catastrophic shallow-water carbonate platform collapses re-deposited in relatively deep-water inner foredeep settings developed at the front of the advancing Dinaric thrust system. These thick, basin-wide mass transport deposits (MTDs) record the catastrophic emplacement of bipartite slide masses, comprising a lower coherent/cohesive blocky flow and an upper grain/turbulent flow. We here present the results of micro- to outcrop-scale structural analyses, constrained by stratigraphic and sedimentologic observations, performed to identify the internal deformation mechanisms and the emplacement processes of four of the largest MTDs exposed in two large three-dimensional outcrops: the Vernasso (NE Italy) and Anhovo (W Slovenia) open-pit quarries. Our results reveal a variety of primary (sedimentary) soft sediment deformation structures testifying fluid overpressure conditions within the brecciated, fine-grained matrix that sustain, intrude and surround slide blocks and clasts. Meso-scale structural analyses unraveled paleo-transport directions toward the N for the Vernasso quarry and toward the S for the Anhovo quarry. This suggests a forced propagation of the mass transport events controlled by the shape of basin, and reinforces the interpretation of different source areas related to multiple collapses from a carbonate platform rimming the southeastern tip of the basin. These units are thought to represent exhumed fossil examples of the MTDs extensively mapped in the present-day, carbonate-dominated continental margins, and thus, considered as reliable analogues for integrated studies.

The paper aims to present the geology of the western part of the Classical Karst (NW Dinarides), located at the border between Slovenia and Italy. The work is based on archive, published and new data collected by Slovenian and Italian researchers within several scientific national and Cross Border Cooperation projects. The map, produced at a scale of 1:50,000, summarizes the lithological and structural setting and is supplemented by three geological cross-sections of the study area.

Understanding the factors that contribute to anisotropic slopes instability provides important information for safe mining operations in flysch-type units. This work presents the results of sedimentological and structural analyses performed in the Anhovo Quarry (Western Slovenia), where carbonate-rich material is excavated from exhumed mass transport deposits (MTDs), generated by submarine landslides during late Paleocene. The architecture of mine design presents major challenges in terms of ideal configuration for optimized mining processes in one the largest MTDs, the Rodez Unit. A gradual increase in complexity of the slope failure mechanism is associated with different localized degrees of lithification and diagenesis depending directly on the mass transport processes. An estimation of the stability of the quarry walls is therefore based on the correct understanding of the distribution of structural features and anisotropies caused by the depositional characters of the MTD, such as paleo-transport directions, erosive potential and relationships with the basin physiography. Quarry operation planning in MTDs requires a multilayered approach for the geomechanical stability analysis, especially in terms of genesis, diagenesis, and anthropogenic activity. .

Micro-to meso-scale outcrop studies on selected field analogues allow direct calibration and testing of geophysical interpretations performed on mass transport deposits in modern continental margins, in terms of genetic processes and sliding dynamics. This comparative approach provides important information for forecasting and mitigating submarine landsliderelated geohazards. The comparison of fieldwork studies (i.e., siliciclastic, carbonate and mixed, seismic-scale Eocene-Oligocene submarine mass transport deposits of the Northern Apennines in Italy, central Pyrenees in Spain and the north-western Dinarides in Italy/Slovenia) with multibeam bathymetric, seismic and drill core data from some modern analogues (i.e., offshore of New Zealand, Japan and Svalbard in Arctic Norway) is proposed in order to upscale the outcrop observations and downscale the geophysical features. Our results show that slide mass mobility is a function of the degree of internal liquefaction/fluidization, mainly achieved at the basal sliding interval and within the slide body. This is due to undrained shearing/loading-unloading of poorly-lithified sediments, and consequent development of fluid overpressure that is able to accommodate deformations at high strain rates. Structures related to these processes are observable at all scales, and represent diagnostic criteria to recognize potentially catastrophic mass transport events.

New data on archeological remains and coastal morphologies have been used to refine published data on the LateHolocene relative sea-level change along the Northeastern Adriatic coasts. Data have been compared with predicted curves, in order to detail the tectonic evolution of the studied area.

Microbialite units are commonly found within the Mesozoic–Tertiary carbonate succession of the Karst District of Slovenia and Italy. They record environmental conditions, which are linked with both local and global events.

2007/2008 Da molti anni i fondali marini dell’Adriatico Settentrionale sono oggetto di interesse scientifico. Si annoverano studi accademici già dal 1792 ma solamente dalla seconda metà degli anni sessanta, grazie agli studi geologici, geofisici e geomorfologici, intrapresi da alcuni ricercatori è stato possibile evidenziare che i fondali marini del Golfo di Venezia unitamente al Golfo di Trieste sono prevalentemente sabbioso-limosi e monotoni dal punto di vista morfologico e delle forme di vita animali e vegetali. Questa monocorde caratteristica del fondo dell’alto Adriatico viene interrotta solamente dalla presenza di elevazioni a substrato roccioso denominate localmente Grebeni, Trezze, Tegnùe e Scagni. I risultati di questo dottorato di ricerca hanno permesso, attraverso l’integrazione di acquisizioni geofisiche, campionamenti diretti in situ, registrazioni video e fotografiche, misure in laboratorio, di ampliare il quadro delle conoscenze acquisite fino ad ora sugli affioramenti rocciosi presenti nel fondale marino dell’alto Adriatico, e di aggiungere nuove indicazioni sull’età dei depositi cementati e sui processi diagenetici che hanno portato alla loro formazione. Dall’attività di studio morfo-batimetrico e sismostratigrafico è stato possibile trarre una prima considerazione sulla distribuzione, numero e forma degli affioramenti segnalati facendo emergere che il loro numero è diseguale nel Golfo di Venezia rispetto a quello di Trieste, con i primi di gran lunga superiori ai secondi, e che questi si presentano in entrambi i golfi eccezionalmente in forma solitaria, normalmente in gruppi di affioramenti di densità variabile da 0,5 sino a 3,25 affioramenti per km2. Dalla tipologia di questi raggruppamenti è stato possibile distinguere quelli a gruppo puntuale, quelli a gruppo allineato ed infine, quelli a gruppo frastagliato. Si è cercato infine di verificare se esistesse un rapporto tra forma di affioramento e processo genetico; è emerso che almeno al momento non si sono riscontrate relazione univoche tra forma e processi diagenetici. Questi avvengono su depositi di ambiente continentale, oppure marino con caratteri molto simili, dove il tipo di deposito sembra essere responsabile solamente di un eventuale effetto accumulo o influenzante il regime di flusso del gas attraverso i sedimenti portando ad una maggiore concentrazione di emanazioni gasose e dunque all’instaurarsi di processi di precipitazione di carbonato di calcio, tipici delle aree di seepage, lungo aree preferenziali. L’indagine sull’immediato sottofondo marino ha messo in evidenza da un lato lo scarso radicamento degli affioramenti nella coltre sedimentaria e dall’altro la presenza di numerose sacche di gas nell’immediate vicinanze degli affioramenti. Lo studio delle sezioni sottili di roccia realizzato con microscopio petrografico ed elettronico in dispersione di energia, ha portato all’individuazione di cementi riconducibili ad una precipitazione avvenuta prevalentemente in ambienti francamente marini subtidali o al limite della fascia più profonda intertidale, mentre in alcuni casi, il cemento è risultato talmente scarso da non permettere alcuna interpretazione. Confrontando i cementi aragonitici a struttura aciculare e/o fibroso raggiata individuati in alcune rocce dell’ alto Adriatico con quelli osservati in lastre carbonatiche campionate all’interno di alcuni pockmarks presenti al largo delle coste norvegesi è evidente una forte similitudine morfologica. In tal senso risulta rafforzata una genesi legata alla fuoriuscita di gas metano originatosi per la combinazione di processi di ossidazione anaerobica e solforiduzione batterica della sostanza organica presente nei sedimenti sottostanti. Dalle analisi isotopiche è emersa la conferma di quanto dedotto dalla semplice forma dei cementi. E’ risultato che il rapporto isotopico del carbonio dei campioni bulk analizzati (frazione detritica + bioclastica) si colloca in un intervallo compreso tra -26,30 / -10,28 ‰ , mentre sono risultati valori nettamente più negativi per quanto riguarda i soli campioni di cemento accuratamente prelevato al microscopio (intervallo compreso tra -49,8 / -38,0 ‰). Infine sono state condotte analisi 14C su due campioni di cemento aragonitico e su tre bioclasti inglobati sulla roccia cementata. E’ risultato che la probabile età delle torbe da cui è iniziato il processo di metanogenesi è compatibile con l’età dei cementi analizzati, che risulta variabile da 15.940 a 21.700 anni B.P., come d’altra parte supposto in altri lavori, mentre la cementazione è avvenuta in lassi di tempo inferiori da 8.220 a 4.990 anni B. P. e si è realizzata in tempi probabilmente recenti e tutt’oggi in atto. A conclusione di questo dottorato è possibile evidenziare che è stata raggiunta una esaustiva conoscenza degli affioramenti rocciosi presenti nel fondale marino dell’alto Adriatico, definendo dettagliatamente la loro diffusione, e per alcuni la loro genesi ed età. E’ stata accertata la formazione metanogenica di alcuni di questi litosomi e la loro formazione in ambiente marino. Per altri affioramenti questa definizione non è stata possibile a causa della scarsità di materiale reperibile per analisi ottiche ed isotopiche. E’ stata accertata per questi litosomi l’età olocenica della loro cementazione; rimane comunque, da accertare se questo tipo di genesi sia la sola responsabile delle migliaia di rocce sottomarine individuate, o se questa sia solamente quella preponderante su altre tipologie, attualmente non confermate. Per ultimo ma non meno importante, va sottolineato che anche in relazione a questo dottorato di ricerca si assiste oggi ad una maggior attenzione della classe politica locale e nazionale al problema della gestione e della difesa di questi particolari geo-biositi che oltretutto possono essere utilizzati e valorizzati come aree di ripopolamento bentonico e nectonico e che recentemente sono stati censiti come probabili aree SIC. XX Ciclo 1970

Upper Cenomanian limestones exposed in southern and western Istria, (Croatia) are rich in radiolitid remains and also contain dinosaur footprints. At investigated localities, the rudists are elevator types and mud-supported sediment-dwellers which thrived in the soft substrate, where dinosaurs have left footprints. Dinosaur tracks are preserved in both types of subtidal limestones, while radiolitid congregations laterally appear and disappear within foraminiferal-peloidal limestones.The presence of dinosaur footprints on the upper bedding plane of rudist floatstones, implies that the Istrian part of the Upper Cenomanian carbonate platform was a shallow protected platform interior.

About sixty well sorted (average diameter 0.8 cm) volcanic clasts with tholeiitic affinities were found in the midst of an lower Maastrichtian conglomerate outcropping close to Bovec (Slovenian Basin, NW Slovenia) and interpreted as evidence of a deltaic system. The clasts appear to be variably spilitized (i.e. albitization of plagioclase and anomalous Na content), however, they do not show any evidence of sub-solidus recrystallization. The analysis, carried out on nineteen selected samples, point out similar petrographic textures and a strong arc-type chemical signature (i.e. deep Nb negative anomaly, quite low La/Sm and Th/Zr ratio and normative corundum). Chemical data allow us to distinguish, for comparable grade of evolution, variable LREE contents which cannot be related only to crystal fractionation or to a variable grade of crustal contamination, but require compositional differences in the protolithic sources. To have an indication of the provenance of these clasts, and about their related hydrographic system, their chemical features were compared to those of similarly evolved pre-Maastrichtian magmatic rocks of different ages, locations and geological settings, mainly belonging to the Dinaridic-Carpathian region. Such a comparison seems to indicate a particular affinity with the arc-type magmas which outcropped in the Vardar Ocean in Jurassic times. In particular Bovec clasts show strong chemical similarities with metabasites from the ophiolitic complexes of the Evros (Rhodopes) and Vardar Zone, while they appear quite different from both the more depleted samples from Bükk Mountains (Hungary), and all the calc-alkaline compositions considered. The grain size of the clasts and the complete absence of recrystallization suggest a provenance from a quite delimited and close protolithic area (1–3 hundred kilometers) that did not suffer from sub-solidus recrystallization during Late Cretaceous times

In central Istria (western Croatia) a middle Eocene unit, some tens of metres thick, marks the transition from shallow-water carbonate to deeper-water clastic sedimentation. This unit consists of a basal interval, rich in macrofossils, made of clayey fossiliferous wackestones and packstones (known as Marls with crabs) and of an overlying marly interval (Globigerina Marls). Integrated paleontological, sedimentological, and petrographical analyses of three key sections, supplemented with data from several other sites, reveal the history of the depositional environment and the changes that occurred up-section in the carbonate deposition and the faunal assemblages. Palaeobathymetric reconstruction, based on the benthic and planktonic foraminiferal assemblages, shows a rapid deepening-upward from the base (palaeodepth is about 200 m) to the top (about 1000 m) of the unit. The base of the unit represents a condensed section that contains abundant macrofossils consisting of autochthonous (mainly decapod crustaceans and deep-water mollusks) and allochthonous (macroforaminifers and shallow-water mollusks) benthic, as well as pelagic (nautiloids and nektonic remains) and pseudoplanktonic (teredinids and ostreids) forms. The abundance of decapod crustaceans, probably represented by only one species that lived in deep-water, can be correlated with the substantial arrival of plant organic detritus at the bottom. The further deepening of the environment caused the disappearance of most of the benthic autochthonous forms. Dropstones, wood-boring bivalves and other pseudoplanktonic forms, and vegetation remains are mainly found within and just above the basal fossiliferous horizon. The abundance of vegetation remains and teredinids reflects the input of wood into deep-marine environments and condensation associated with sediment starvation, both related to a phase of sea-level rise. Dropstones were transported by vegetation rafting and, probably, at a lesser rate, by kelp rafting. Petrologic studies of the dropstones provide information on the source areas (deltaic areas of the Collio region, NE Italy) and on the little known palaeogeography of the Southern Alps and Outer Dinarides during the Lutetian tectonic phase of regional relevance.