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Resedimented carbonates constitute the bulk of the Dinaric Foreland Basin fill in northern Dalmatia, Croatia. The wedge-top basin comprises an array of asymmetrical sub-basins filled with the Promina Beds – a ~2000 m thick calciclastic succession of deep neritic to marginal-marine and alluvial deposits of middle Eocene to Oligocene age. These calciclastic sediments derive from redeposition of uplifted and eroded carbonates formed originally on the Adriatic Carbonate Platform during the Cretaceous, and intra-basinal carbonate ramps during the Eocene. Repetitive resedimentation phases involved carbonate debris of different age and grain size included in various transport and depositional mechanisms, resulting in diverse deposits over a relatively small area. The most conspicuous among these are mass-transport deposits (MTDs) that record subaqueous gravity processes in deep-marine and shallow-marine settings. Their features suggest that their transport direction was perpendicular to the southeast-trending structural lineaments. Most of them were triggered during the Bartonian and Priabonian, especially in the Korlat and Novigrad sub-basins which differ from others and from each other in resedimentation processes and host deposits. Specifically, the Korlat sub-basin is characterized by large limestone olistoliths and associated bipartite megabeds encased in deep neritic hyperpycnites. The origin of these blocks and gravity-flow deposits is attributed to major gravitational collapses of consolidated and unconsolidated sediments of Lutetian carbonate ramps, respectively. Contrarily, MTDs in the Novigrad sub-basin occur in offshore and offshore- transition strata and include calcilutite and calcarenite slumps, bioturbated conglomeratic slump-debrites with a “dough-like” appearance, and debrites deposited from debrisflows of variable competence. We suggest that these MTDs were triggered in fairly shallow water by a combined effect of strong earthquakes and sediment destabilisation due to pore water overpressure during forced regressions caused by sub-basin tectonic development. The results show that the integration of facies and microfacies analyses plays a crucial role in unraveling the intricate relationship between tectonics, sedimentation and relative sea-level changes.

Mass transport deposits (MTDs) are common in relatively deep and tectonically active settings and represent distinct “events” in the development of a sedimentary basin. The present study from the Dinaric Foreland Basin documents a rare example of a 300 m thick shallow-marine succession characterised by about 50 MTD units interbedded with calcilutites and calcarenites of the offshore and offshore transition zone. The succession crops out in the vicinity of Novigrad in northern Dalmatia, Croatia, and represents the infill of a sub-basin that developed in the wedge-top part of the evolving foreland during the Middle Eocene to Early Oligocene (Ćosović et al., 2018). Four types of MTDs, ranging in thickness from 20 cm to 600 cm and extending for more than 600 m have been identified: (1) slumped offshore and offshore transition strata, commonly displaying convoluted bedding and signs of sediment torsion ; (2) slides comprising blocks of clast supported beachface conglomerates and/or bioturbated shoreface calcarenites encased in offshore strata ; (3) blocky-flow deposits comprising matrix-supported conglomerates with large blocks of deformed shoreface and/or offshore transition strata ; and (4) debrites comprising massive, matrix- supported conglomerates. Large calcarenite and/or conglomerate blocks in MTD types 2 and 3 were incorporated as consolidated blocks into the mass transport, suggesting significant erosion of older units. The study succession shows several transgressive-regressive cycles and progressive deepening of the sedimentary basin with an accompanying increase in MTD incidence, especially of types 2–4. Small-scale slumps of type 1 occur throughout the succession and commonly within transgressive offshore deposits. Where parasequences can be recognised, other types of MTDs tend to be associated with regressive offshore transition and offshore deposits. Relative sea- level fluctuations probably stemmed from non- synchronous uplift and subsidence of neighbouring blind thrust anticlines, possibly leading to coeval transgressions and regressions on opposite limbs of the same synclinal sub-basin (Mrinjek et al., 2012 ; Ćosović et al., 2018). The multitude of MTDs in the uppermost part of the succession was likely favoured by basin floor steepening associated with increasingly frequent uplift pulses, possible emergence and erosion of the basin bounding growth anticline. Contrarily, basin deepening and ramp extension during transgressive stages could have favoured mass-flow transformations. A generic relationship between relative basin depth and MTD type is suggested, whereby slides would be indicative of a somewhat shallower environment compared to blocky flow deposits and debrites. Such alternation of various types of MTDs in a shallow-marine succession attests the colossal power of syn- sedimentary tectonics during basin development and may give a clue on small scale transgressive regressive cycles when flooding surfaces and/or correlative conformities cannot be readily identified.

The Promina Beds in northern Dalmatia are a more than 2000 m thick calciclastic succession of Middle Eocene–Early Oligocene age, constituting the infill of the piggyback part of the Dinaric Foreland Basin (Fig. A, B ; MRINJEK et al., 2011 ; ĆOSOVIĆ et al., 2018). Progressive thrusting due to the collision between Africa and Europe compartmentalized the basin and led to the formation of an array of narrow marine sub-basins, separated from one another by ridges developed on blind-thrust growth folds. These sub-basins had steep flanks, whereby dynamic synsedimentary tectonic activity resulted in drastic facies changes over short distances, including frequent slumping. Slumps in the Promina Beds occur in marine deposits of different age and in different sub basins (Fig. B). They commonly display contorted strata (Fig. C–E) and evidence of sediment torsion, resulting from gravitational en masse movement of sediment along steep and unstable slopes. Their transport direction can be inferred from their geometry and in most cases it is perpendicular to the southeast- trending structural lineaments (Fig. B). Most of the documented slumps show transport direction towards the south-west (Fig. B, E). These observations indicate that the sub-basins were likely asymmetrical, i.e. steeper along their NE margin, which increased slope instability and its susceptibility to repeated slumping. Alternatively, tectonic perturbations associated with progressive nappe thrusting might have been more severe along the sub- basins’ NE margins. Slumps are locally associated with micro-faults formed in fairly coherent sediment, resembling the segmented zone of a typical seismite (SEILACHER, 1969), which corroborates the latter assumption and suggests that slumps were most likely triggered by earthquakes and enhanced by steep basin morphology. In places, however, slumped deposits were emplaced from other directions and could have been triggered by major regional earthquakes or locally oversteepened north- eastern anticline limbs. By assessing slump directions and age of the deposits in which they are encased, it is possible to reconstruct basin development dynamics, e.g., discern between in-sequence and out-of-sequence thrusts or identify possible blind-thrust anticlines that nowadays may be concealed by topography or sediment cover.

In the study of Eocene carbonate succession in the Dinaric Foreland Basin (northern Dalmatia, Croatia), integrated palaeontological and sedimentological data document a range of successive carbonate ramps formed intermittently during the basin tectonic evolution and progressive contraction. The late Ypresian Foraminiferal Limestones are overlain unconfortably by a succession of early Lutetian limestones, the Upper Nummulitic Limestone or Lithotamnium Limestones. The study of Larger benthic foraminifers (LBF) is important in the sequence-stratigraphic analysis of the sedimentary succession, particularly in the distinction and timing of its component systems tracts. The bathymetric assessment based on LBF has made it clear that these biogenic limestones signify an increase of water depth and hence belong to the transgressive tract. The late Ypresian Foraminiferal Limestone, rich in alveolinids, conical agglutinated foraminifers and complex miliolids, was deposited during a global sea-level highstand and this early period of low-rate foreland subsidence well-balanced by the rate of organic productivity. The slight bathymetric fluctuations indicated by facies changes in the lower part of this succession seem to reflect the eustatic cycles Yp8–10 (sensu Snedden & Liu, 2010), the end-Ypresian emergence of the carbonate ramp at the highstand peak of cycle Yp10 was clearly caused by local tectonics. The eustatic signal becomes far less recognizable in the Lutetian to Priabonian part of the stratigraphic succession, where the local changes of relative sea level are mainly opposite to the eustatic ones. Nummulitids, asterigerinids, silvestriellas and different genera of encrusting foraminifers were dominant constituents in LBS assemblages along with corallinaceans. The late Ypresian carbonate-ramp deposits were developed on the retreating forebulge flank of a shallow-marine early foredeep basin. The younger, middle to late Eocene carbonate ramps formed episodically as perched isolated features on blind-thrust anticlinal ridges in a bathymetrically diversified wedge-top basin, where phases of biogenic and clastic carbonate sedimentation alternated due to disharmonic thrusting and frequent sea-level changes.

Stručna ekskurzija po Prominskim naslagama sjeverne Dalmacije, pregled najpoznatijih nalazišta s opisom tragova fosila

Uz istočnu obalu Jadranskoga mora, smjerom SZ-JI pružaju se izdanci paleogenskih naslaga koji tvore manje-više kontinuirani pojas (različite širine). U kanjonu rijeke Čikole (sjeverna Dalmacija) provedena su istraživanja paleogenskih naslaga, uzorkovan je te sedimentološki i mikropaleontološki interpretiran 308 m debeo slijed naslaga. Najstariji istraživani sedimenti su plitkomorski vapnenci gornjokredne (kampanske) starosti, na koje se transgresivno nastavljaju naslage paleogenske starosti. Najstariji dio paleogenskih naslaga sastoji se od ciklične izmjene vapnenaca tipa mudstone do packstone u kojima nalazimo ostatke ostrakoda, rijetke bentičke foraminifere i oogonije chara.U istim sedimentima su nađeni ostaci gastropoda (Stromatopsis sp.). Ciklus završava tankolaminiranim vapnencima s proslojcima ugljena. Prepoznata su ukupno 24 ciklusa, ukupne debljine 26 metara. Sedimentološke strukture i teksture te fosilni sadržaj upućuju na taloženje u okolišima smanjenog saliniteta (boćati okoliši) niske energije. U središnjem dijelu paleogenskog slijeda, izmjenjuju se sitnozrnati foraminiferski packstone i wackstone tipovi vapnenaca gornjoiperske starosti (SBZ 12, SERRA-KIEL et al., 1998), koji sadrže brojne velike bentičke foraminifere (alveoline poput Alveolina aff levantina Hottinger, konične foraminifere poput Coskinolina liburnica (Stache), HOTTINGER, 1966 ; HOTTINGER & DROBNE, 1984) sa slojevima gdje su foraminifere rijetke. Najmlađe istraživane naslage su vapnenci wackestone do grainstone tipa s kućicama numulita i ortofragmina, a sam slijed završava vapnencima tipa grainstone u kojima su brojne kućice velikih bentičkih foraminifera (numuliti i ortofragmidi), fragmenti koralja, mahovnjaka i ostaci crvenih algi. S obzirom na fosilni sadržaj (velike bentičke foraminifere) te strukturne i teksturne osobine, vapnenci s velikim bentičkim foraminiferama su se taložili na prostoru unutarnjega dijela karbonatne rampe (DROBNE et al., 2010). Foraminiferski vapneci u kojima numuliti i ortofragmine dominiraju, ukazuju na taloženje u središnjem dijelu karbonatne rampe (ĆOSOVIĆ et al., 2004) . Istraživani slijed foraminiferskih vapnenaca taložio se u plitkom i relativno širokom bazenu koji se počeo formirati nakon gornjokredne tektonske dezintegracije Jadranske karbonatne platforme kao posljedica dinarske orogenetske kompresije (VLAHOVIĆ et al, 2005). Iako se dubina bazena ispred uzdižućeg Dinarskog planinskog pojasa postupno povećavala, stvaranje akomodacijskog prostora bilo je najvećim dijelom u ravnoteži s brzinom karbonatne sedimentacije. Taloženje ovog debelog slijeda agradacijskih vapnenaca signalizira početak stvaranje Dinarskog predgorskog bazena i najava je „burnih događanja“ koja su uslijedila u gornjem eocenu (BABIĆ et al., 2010 ; VLAHOVIĆ et al, 2012). BABIĆ, LJ., ZUPANIČ, J. & LUŽAR-OBERITER, B. (2010): Evolution of a Dinaric foreland basin fi ll: fl ysch and molasse of North Dalmatia.– In: HORVAT, M. (ed.): 4th Croatian Geological Congress, Šibenik 2010, Excursion Guide-book, Zagreb, 179–201. ĆOSOVIĆ, V., DROBNE, K., MORO, A. (2004): Paleoenvironmental model for Eocene foraminiferal limestones of the Adriatic carbonate platform (Istrian peninsula).- Facies, 50, 61-75. DROBNE, K., ĆOSOVIĆ, V., MORO, A., BUCKOVIĆ, D. (2011): The role of the Paleogene Adriatic carbonate platform in spatial distribution of alveolinids.- Turkish journal of earth sciences, 20/6, 721-751. HOTTINGER, L., DROBNE, K. (1980): Early Tertiary conical imperforate foraminifera.- Razprave, 4 razr. SAZU, 22, 90 p., Ljubljana. HOTTINGER, L. (1960): Über paleocaene und eocaene Alveolinen.- Eclogae geol. Helv, 53, 265-283. SERRA-KIEL, J., HOTTINGER, L., CAUS, E., DROBNE, K., FERRÀNDEZ, C., JAUHRI, A. K., LESS, G., PAVLOVEC, R., PIGNATTI, J., SAMSÓ, J. M., SCHAUB, H., SIREL, E., STROUGO, A., TAMBAREAU, Y., TOSQUELLA, J., ZAKREVSKAYA, E. (1998): Larger foraminiferal biostratigraphy of the Tethyan Paleocene and Eocene.- Bull. Soc. Géol. France, 169/2, 281-299. VLAHOVIĆ, I., MANDIĆ, O., MRINJEK, E., BERGANT, S., ĆOSOVIĆ, V., DE LEEUW, A., ENOS, P., HRVATOVIĆ, H., MATIČEC, D., MIKŠA, G., NEMEC, W., PAVELIĆ, D., PENCINGER, V., VELIĆ, I. & VRANJKOVIĆ, A. (2012): Marine to continental depositional systems of Outer Dinarides foreland and intra-montane basins (Eocene-Miocene, Croatia and Bosnia and Herzegovina). - In: Journal of Alpine geology, 54. 29th IAS Meeting of Sedimentology - Schladming, Austria 2012. Field trip guide, 405-470. VLAHOVIĆ, I., TIŠLJAR, J., VELIĆ, I. & MATIČEC, D. (2005): Evolution of the Adriatic Carbonate Platform: paleogeography, main events and depositional dynamics.− Palaeogeography, Palaeoclimatology, Palaeoecology, 220, 333–360.

This combined micropalaeontological and sedimentological study is based on the middle to late Eocene deposits in the Novigrad sub-basin, one of several SE-trending narrow synclinal troughs within the evolving thrust wedge-top Dinaric foreland basin of northern Dalmatia. Deposits of the subbasin SW limb indicate repetitive clastic and carbonate-ramp sedimentation, apparently driven by the emergence and submergence phases of the trough-bounding blind-thrust growth anticline.Phases of clastic sedimentation involved progradation of a wave-dominated gravelly shoreline (foreshore) facies over a sandy shoreface covering heterolithic sand-mud offshore transition and muddy offshore deposits. The offshore-transition and offshore deposits are commonly intercalated with foreshorederived, gravelly debris-flow and slump deposits indicating pulses of gravitational resedimentation, probably triggered by an excessive uplift and/or normal faulting of the anticline flank. Phases of biogenic carbonate sedimentation, attributed to the anticline submergence, were dominated by the accumulation of large benthic foraminifers (nummulitids, operculinids, orthophragminids, aborescent foraminiferids, asterigerinids, rhapydionids and alveolinids) and their fragmented tests along with bryozoans, echinoids, corals and red-algae debris. The composition of foraminifer assemblages, their detailed systematic and functional morphologic analysis, the preservation degree of their tests (varying from poor to good, including micritization and overgrowth by either foraminifers or algae) and the abundance of certain morphotypes (limestones, mostly wackestones and packstones, with a matrix composed of fine bioclastic hash) are thought to indicate a carbonate ramp depositional setting. The carbonate depositional system probably comprised an array of nummulite banks formed close to the fair-weather wave base, possibly with inner ramp lagoons and an open-marine middle/outer ramp zone. The foraminifers indicate a Priabonian age of the carbonate deposits in the Novigrad sub-basin, which highlights the high frequency of carbonate/clastic environmental changes. The demise of large benthic foraminifers in each carbonate unit seems to be a result of the environment shift from low-nutrient oligotrophic and euphotic conditions – favourable for shallow-water benthic foraminifera – to increasingly eutrophic conditions due to the increase of erosion and input of terrigenous nutrient associated with a relative sea-level fall. The carbonate units on the synclinal sub-basin flank are thus interpreted to be transient carbonate ramps developed during short-term relative sea-level rises and terminated by relative sea-level falls. The short-term changes between clastic and carbonate sedimentation on the sub-basin flank may be due to a combination of the 4th-order (Milankovitch) eustatic cycles and the tectonic pulses of structural evolution of the wedge-top foreland basin.

The Eocene–Oligocene Dinaric peripheral foreland basin in the northern Dalmatia developed by a SW-directed orogenic thrusting and comprised two distinct palaeogeographic zones: a shallowmarine proximal foreland where a calciclastic succession of neritic to terrestrial sediments known as the Promina Beds was deposited, and a deep-water distal foreland accumulating turbiditic deposits known as the Dinaric Flysch. The proximal foreland evolved gradually into a thrust wedge-top (‘piggy-back’) basin, while the tectonically quieter distal foredeep was filled up with the Dinaric Flysch and was eventually onlapped by the Promina Beds. The progressive tectonic shortening of the orogenic thrust wedge caused formation of a series of SW-vergent blind-thrust growth folds within the wedge-top basin, resulting in its compartmentalization into an array of narrow, high-relief marine sub-basins (synclinal troughs), where the main part of the Promina Beds succession was deposited. An illustrative example of these troughs is the Novigrad sub-basin, a SE-trending synclinal swale formed close to the orogen front and filled with sediments in the middle to late Eocene. The two opposing limbs of the asymmetric synclinal trough show markedly different styles of sedimentation. The steeper NE limb hosted coarse-grained shoal-water to Gilbert-type deltas, whereas the gentler SW limb hosted a wave-dominated gravelly shoreline (foreshore zone) with sandy shoreface, heterolithic sand-mud offshore transition and muddy offshore zone. The offshore-transition and offshore deposits here are commonly intercalated with foreshore-derived, gravelly debris-flow and slump deposits, which represent resedimentation pulses triggered most probably by a normal faulting of the syncline limb growing in its relief. A similarly contrasting style of sedimentation is recognizable on the opposing limbs of other synclinal troughs in the Dinaric wedge-top basin in northern Dalmatia, with the steeper NE limb shedding sediment gravity flows and the gentler SW limb hosting a littoral system prone to gravitational collapses and resedimentation. This evidence indicates a wedge-top basin turning into a system of blind-thrust growth folds as a result of tectonic contraction. The structural development in such a deformation system is intricate, as it may involve both in-sequence and out-of-sequence thrusts, as well as back-thrusts and related pop-up ridges. In addition, the entire thrust wedge-top basin may be episodically uplifted piggy-back by its soling master thrust and be episodically subsiding due the crustal load of orogen thrust-sheets. The inherent shortterm variability in the syndepositional tectonic development of a wedge-top basin bears several important stratigraphic ramifications as to the facies record and relative sea-level changes: (1) drastic facies changes may occur over short distances away from the orogenic front ; (2) a forced or normal regression on one limb of a synclinal trough may be coeval with a transgression on the other limb ; (3) some of the marine transgressions and regressions may occur synchronously on both limbs of the synclinal trough, irrespective of the difference in local bathymetry and sedimentary environment ; and (4) progressive unconformities may be a common feature of the basin-fill succession. This Dinaric case study may be relevant to a palaeogeographic development of the wedge-top parts of the ‘inner’ Carpathians and other orogenic belts.

Larger benthic foraminifera (LBF) from two spectacularly exposed carbonate mounds that crop out in the SE part of the Promina piggy-back basin (Outer Dinarides, Croatia) were used to define the origin and the mechanisms that produced them. The Promina Beds are ca 2000 m thick and are a regressive molasse succession of neritic to terrestrial calciclastic deposits of mid Eocene to Oligocene age accumulated in the Dinaric foreland zone. Limestones with LBF and corals occur in the upper part of the clay/marls neritic succession. In order to estimate the relative bathymetry of deposition and to build a depositional model, textural analysis, nummulitid (Nummulites s.str and Asterigerina/Amphistegina sp.) and orthophragminid test size and shape, and the types of light-dependent skeletal components were studied. Five types of facies were recognized: Facies #1, packstones in which LBF (nummulitids) make up 20% of the rock volume while small bioclasts (fragments and whole tests) comprise 10 % are dispersed in micrite matrix ; Facies #2, a red-algae-rich coral rudstone with a pack-wackestone matrix ; Facies #3, well sorted, fine-grained or poorly sorted coarse-grained skeletal packstones with numulitids, bryozoans, coralline algae, and very rare, smaller benthic foraminifera ; Facies #4, coral boundstone with abundant red algae in a mud-dominated matrix ; and Facies #5, nummulitid packstones, with Nummulites sp., Operculina sp. Discocyclina radians and Asterocyclina stellata, coralline algae, very rare smaller benthic foraminifera. Facies associations, textures, and photodependent components (T/D ratio, test morphology) indicate these cycles with corals and coralline algae to have grown in the mesophotic (facies # 2, #3 and #4) and euphotic (facies #1 and #5) zones and in low energy conditions below fair-weather wave base, where they were only occasionally influenced by exceptional storms. Facies #1 is assigned to a maximum water depth of 10 m and the deposits are winnowed, probably from the action of bottom currents. The prevalent deposits are unsorted Discocyclina–Asterocyclina micrites (facies #5), which were deposited at a maximum water depth of 50–60 m suggested by this large, hyaline foraminiferal assemblage.

The Dinarides form a mountain chain extending in NW–SE direction along the northeastern Adriatic coast, connecting the Southern Calcareous Alps to the north with the Albanides and Hellenides-Taurides to the south. The mountain chain consists of a strongly tectonized, thick rock succession spanning a stratigraphic range from Carboniferous to Quaternary. The zone close to the Adriatic coast - where the field-trip area is located - is known as the Outer or Karst Dinarides, composed mainly of carbonate rocks. The more inland zone, between the Karst Dinarides and the Pannonian Basin, is known as the Inner Dinarides, composed mainly of deeper-marine sedimentary rocks and ophiolites. Although the carbonate deposition commenced in Carboniferous and significantly increased in the Late Permian and Triassic, the major part of the carbonate deposits, which belong to the Adriatic Carbonate Platform (AdCP), formed during Jurassic and Cretaceous. The AdCP formed on the Adria Microplate, recording disintegration of a vast para-Tethian carbonate platform into several smaller ones during the late Early Jurassic (Toarcian). The AdCP was a relatively stable shallow-marine area until the Late Cretaceous, when it started to be gradually deformed, tectonically disintegrated and mostly emerged by SW–NE oriented compression. More or less continuous shallow marine sedimentation across the K/T boundary is recorded only at the northwestern and southeastern margins of the AdCP. Deposition during Eocene, Oligocene and Miocene was significantly influenced by tectonic deformation of the former Adriatic Carbonate Platform. Therefore, although Outer Dinarides are famous for their thick succession of shallow-marine carbonate rocks, which were already main topic of numerous field trips, including several excursions at two IAS meetings (Split 1983, Opatija 2003), we believe that post-platform development is also very interesting. This field trip encompasses three different Cenozoic successions deposited above the Mesozoic platform carbonates: (1) Massive Cenozoic carbonate breccia of the Karst Dinarides: the Velebit breccia, (2) The Eocene-Oligocene Promina Beds of the Dinaric foreland basin in northern Dalmatia, and (3) Miocene intra-montane lacustrine basins of Outer Dinarides (Croatia and Bosnia and Herzegovina).

In order to add more information about complex origin of Promina Beds (traditionally interpreted as Paleogene molasse of Dinarides), two sections (Lišani Ostrovački and Ostrovica, Central Dalmatia, Croatia) have been studied in detail. Sampled carbonate sequences contain predominantly coralline red algae, larger benthic foraminifera and corals. Based on sedimentary textures, nummulitid (Nummulites s.str and Asterigerina sp.) test shapes and the associated skeletal components, altogether three types of the Middle Eocene (Lutetian to Bartonian) facies were recognized. The Ostrovica section is composed of alternating couples of marly limestones and marls, several decimeters thick with great lateral continuity. Two facies which vertically alternate are recognized as Nummulites - Asterigerina facies, where patchily dispersed large, robust and party reworked larger benthic foraminifera constitute 20% and small bioclasts (fomaniniferal fragments and whole tests less than 3 mm in diameters) 10% of rock volume and, Coral - Red algal facies with coral fragments of solitary and colonial taxa up to 1 cm in size constitute 5 - 40%, red algae 15 - 60% and lager benthic foraminifera up to 5% of rock volume. The textural and compositional differences among the facies suggest rhythmic exchanges of conditions that characterize shallower part of the mesophotic zone with abundant nummulithoclasts with deeper mesophotic, lime mud-dominated settings where nummulitids with the flat tests, coralline red algae and scleractinian corals are common. The scleractinian corals (comprising up to 20% of rock volume) encrusted by foraminifera (Acervulina, Haddonia and nubeculariids)or coralline red algae and foraminiferal assemblage made of orthophragminid and nummulitid tests scattered in matrix, are distributed uniformly throughout the studied Lišani Ostrovački section. In the central part of section, wavy to smooth thin (< 1 mm) crusts (laminas) alternating with encrusted corals occur. The characteristics of associated fauna and spatial relationship between corals and laminations indicate that this facies originated in a mid–ramp (shelf) setting.

The Dinaric foreland basin of Croatia developed through the tectonic deformation and marine drowning of an emerged and denudated Cretaceous carbonate platform due to the SW-directed orogenic compression. The proximal zone of the basin was filled with a calciclastic succession of Eocene−Oligocene neritic to terrestrial deposits, ~2000m thick, traditionally referred to as the Promina Beds. The distal zone was filled with a coeval turbiditic succession of the Dinaric Flysch, which is locally overlain by the Promina Beds. The Promina Beds recorded syn-tectonic sedimentation in an evolving orogenic wedge-top (‘piggy-back’) basin. This sedimentary succession forms a SE-trending outcrop belt ~80 km long and ~20 km wide in the northern Dalmatia, where it has been studied by regional mapping and detailed logging over the last three decades. The development of the wedge-top basin is recognized to have involved formation of a series of blind-thrust growth folds, before the soling thrust system eventually extended far enough to establish the wedge-top basin’s outer limit The effects of the syn-depositional folding included: (1) formation of incipient topographic ridges that were high enough to avoid an early drowning and hosted accumulation of weathering products that gave rise to bauxites ; (2) development of ‘classical’ progressive unconformities ; (3) deposition of differing facies successions on the opposite limbs of an anticline, with both limbs synchronously recording forced regressions due to the anticline growth and transgressions due to the foreland subsidence driven by crustal loading ; and (4) deposition of contrasting facies successions on the opposite limbs of a growing syncline, with the forced regression on one limb possibly corresponding to a transgression on the other limb, or vice versa, in the case of non-synchronous thrusting. The development of blind-thrust folds in the proximal foreland basin thus resulted in rapid lateral changes in sedimentary facies successions and their thicknesses as well as a spatially differential record of relative sea-level changes. Similar syn-tectonic phenomena can be expected to have occurred in other foreland basins and should be taken into account in the stratigraphic analysis of basin-fill sedimentary successions.

The Karst Dinarides are part of the Alpine chain that parallels the NE Adriatic coast, formed during Oligocene and Miocene deformation of a thick succession of predominantly carbonate rocks, Carboniferous to Eocene in age. A remarkable lithological unit of the Karst Dinarides is a massive Tertiary carbonate breccia. It covers 1011 km2 ; the three largest outcrops are 695, 115 and 22 km2, respectively (82% of a total area). The rest comprises more than 400 smaller outcrops. Thickness data on the breccia are few, but in places it is more than 500 m thick. The breccia is massive, clast-supported, non-bedded, and lacks visible sedimentary structures. Clasts are mostly angular and poorly sorted, ranging in size from less than 1 mm to several centimetres with sporadic cobbles and boulders. Almost all clasts were tectonized before final deposition, as shown by truncated, calcitefilled fractures. Rare clasts of similar older breccia indicate a polyphase origin. Clasts were mostly derived from the surrounding rocks. The grey, yellowish, or reddish carbonate matrix is composed of small lithoclasts and recrystallized calcite. It contains no fossils or structures indicative of subaqueous deposition. A significant criterion for differentiating this breccia from others within the Dinarides are generally steeply inclined, gradational contacts with adjacent rocks. Transitional zones up to several meters wide extend from undisturbed to gradually more tectonized limestones through completely cataclastic limestones and monomict breccia composed of clasts from adjacent limestones to ± polymictic breccias. Significantly, breccia occurrences are mostly along faults and overturned folds with NE vergences, which are very atypical for the Dinarides. The Tertiary carbonate breccia was traditionally interpreted as talus breccia shed from the front of inferred reverse faults or overthrusts. This interpretation ignores several important facts: (i) subvertical and gradational contacts with surrounding rocks, instead of the expected inclined, irregular, sharp contacts, (ii) breccias crop out at hypsometrically highest points, and (iii) stratigraphic succession does not indicate reverse faulting. The breccia was probably initiated by intense in-situ fracturing during compression/transpression, disintegrating the carbonate rocks into cm-sized clasts within km-wide zones. Subsequent extension within overturned structures opened a complex system of deep fractures within the central portion of the breccia. Other breccias formed locally on the surface and portions were reworked into the underlying breccia by surficial processes. The resulting breccias were subsequently tectonized, further altered diagenetically, and intensely karstified and denuded during the long post- emplacement exposure, therefore resulting in a very complex appearance.

The Upper Eocene Benkovac Stone mb. is a shallow- marine, approximately 120 m thick succession of calciclastic deposits, mostly cropping out in a vicinity of Benkovac in the northern Dalmatia. It represents a middle part of Middle Eocene to Lower Oligocene Promina Basin deposits, more than 2000 m thick succession from deep-marine to alluvial facies (MRINJEK et al., 2005). The Benkovac Stone mb. is commonly used architectural and building stone, and is well-known for its excellently preserved trace fossils, which were never, up to now, studied in detail. Two major lithological types within the Benkovac Stone mb. are calciclastic sandstones and calciclastic mudstones. Sandstones were deposited by storms and mudstones were mostly a product of background sedimentation within offshore-transition zone. Sandstones and mudstones are characterized by different trace fossils ichnoassemblages, and individual ichnoassemblages are laterally very variable.

Cjeloviti sažetak priložen je kao privitak ovoga upisa.

Cjeloviti sažetak priložen je upisu.

Clastic deposits in the Konavle area are about 400 m thick, consisting of alternation of sandstone and mudstone beds with rare lensoid conglomerates beds in the upper part. The lower part of succession was deposited in the lower shoreface/off-shore transition environments with abundant amalgamated hummocky cross-stratified beds, the middle part contains thin turbidite beds deposited on a deeper part of a ramp, whereas the upper part with thin conglomerates bodies probably represents a distal prodeltaic facies. Therefore, only the thin middle part of the studied clastic succession of the Konavle region may be referred to as flysch, while lower and upper part were definitely deposited in shallower environments.A combination of sedimentological data and evidences on significant reworking of older deposits indicates that studied clastic deposits have probably been deposited in confined, narrow and relatively shallow piggyback sub-basin which has been in large part filled by resedimented deposits (the mixed sandstones and fine-grained deposits containing reworked older nannoplankton assemblages) from the older basins located in the NE hinterland of Konavle.

The Promina piggyback subbasins display a great variety of facies and depositional trends normal and parallel to their axis, since they were strongly affected by frequent thrust sheets movements (Mrinjek et al., 2005, 2008) The earthquakes, as a direct consequence of thrust dynamics, represented triggers for various soft- sediment deformation features in the most depositional units of the Promina Beds, including (1) slumps, (2) sand dykes, (3) sand volcanoes, (4) load structures, (5) liquefaction pillars, and (6) small-scale normal faults.

The Benkovac Stone Unit is about 100 m thick and consists of carbonate sandstones (up to 35 cm thick, but mainly thinner) interbedded with finer-grained calcareous deposits. Its Late Eocene age was established on the basis of large benthic foraminifera (nummulitids, discocyclinids) and small pelagic globigerinids. Benkovac Stone Unit consists of the offshore transition deposits of a storm-dominated, microtidal shelf variously affected by oscillatory waves and sediment-laden geostrophic currents.

The Canyon Krka and northwestern part of basin revealed several transgressive and regressive systems tracts (FSST, LST, HST) during underfilled and fulfilled phases is and one low- and one high- accommodation systems tracts during overfilled phase. The regressive systems tracts are composed of various gravely delta to braided-plain facies and sandy to gravely beach and shoreface facies whereas fine-sandy inner shelf and muddy outer shelf facies are dominant characteristics of transgressive systems tracts. The low- and one high- accommodation systems tracts are exclusively composed of gravelly to sandy channel braided and flood plain facies. The systems tracts show significant facies changes in their strike direction as well.

The present workshop combines instructive lectures with practical field exercises, which will allow the participants to try this methodological approach in a guided study of one of the well-known Croatian sedimentary successions – the Promina Beds.

Clastic sediments in the vicinity of Virovitica (Northern Croatia) consists of gravels, sands, silt clays and marls. Gravels with discontinuous sheet-like geometry are typical for an alluvial fan system. The most abundant sediment, quartz rich sand, originates from a sandy braided river system. Silt, clays, and marls were deposited in the flood plain. They contain fossil macroflora indicative of moderate climate conditions, including maidenhair leaves (Ginkgo), the presence of which suggests that these sediments were deposited before Pleistocene glaciation.

The results of a detailed isotopic, organic and inorganic geochemical study of a Permian-Triassic section at Rizvanusa locality, Mt. Velebit, was presented. The variations in isotopic ratios record the change of biomass contributions during the Permian to Triassic transition.

Benkovac Stone is a 30 m thick succession within the Promina group. Detailed outcrop analyses have shown that: 1. Almost all sandstone beds display the evidence of wave oscillations. 2. Sedimentation was strongly influenced by storm processes. 3. The major part of the Benkovac stone deposits were produced between the fairweather and stormweather wave base. 4. Shelf environment was steadily, but not amply fed by sands and finer material. It was concluded that Benkovac Stone represents shelfal deposition within a broad and long-term braided-delta depositional setting during its retrogradational phase.

In the Donje Orešje quarry, in SE Medvednica Mt., Miocene sediments transgressively overly Cretaceous limestones. Basal conglomerates, Lithotamnium limestones and partly marls are Badenian in age. Zone Bulimina-Bolivina was determined on the basis of foraminiferal community. Sarmatian marls were deposited continuously. Lower Sarmatian Zones Anomalinoides badenensis and Elphidium reginum, as well as the Middle Sarmatian zone Elphidium hauerianum were recognized. Climate shifts from almost subtropic to moderate can be observed through palinomorph content.

In the Upper Cretaceous limestones of the ist Island there is vertical rhytmic repetition of three limestones types: (1) rudist flatstone with pelagic organisms, (2) wackestone-packstone with with small rudist fragments and pelagic fossils and (3) mudstone -wackestone with with planktonic foraminifers. Structural characteristics indicate depositional environment with resedimented limestones.

Srednje do gornjoecenska formacija Korlat koja se pruža se duž jugozapadnog ruba Prominskog bazena predstavlja najstariji dio Prominskih naslaga. Najveći dio od oko 600 m debele formacije su heterolitski slojevi izgrađeni od vrlo dobro uslojenih kalkarenita (3-40 cm debljine) i 5-300 cm debelih kalklutita i kalksiltita. Osobita značajka kroz cijelu formaciju su pojave velikih vapnenačkih olistolita i debelih slojeva izgrađenih vapnenačkih breča i/ili debelih graduiranih kalkarenita unutar heterolitskih slojeva koji su isključivo izgrađeni od različitih donjo do srednjoeocenskih foraminiferskih vapnenaca The late Middle to Upper Eocene Korlat Formation cropping out along the SW margin of the Promina basin represents the oldest part of the Promina Beds succession. Most of approximately 600 m thick Korlat Unit consists heterolithic beds composed of very well-bedded (3–40 cm thick beds) carbonate sandstones interbedded with 5–300 cm thick beds of fine-grained calcareous deposits. Outstanding characteristic throughout Korlat unit are huge carbonate olistoliths and thick beds composed of carbonate breccias and/or thick graded carbonate sandstones completely encased in the host deposits. Olistoliths and breccias are composed exclusively of various Lower–Middle Eocene foraminiferal limestones.

Na prostoru sjeverne Dalmacije pet je geoloških stupova ranopaleogenskih karbonatnih naslaga (Čikola I i II, Novigrad, Ostrovica i Grabova Glava) bilo predmetom detaljnih sedimentoloških i mikropaleontoloških istraživanja, te su biostratigrafskim pristupom u kombinaciji s mikrofacijesnom analizom rekonstruirani karbonatni taložni okoliši tijekom taloženja. Taloženje se odvijalo u okolišima unutarnjih, srednjih i vanjskih dijelova rampi, a organizmi koji su obilježili te okoliše bile su velike bentičke foraminifere. Tijekom paleogena kolizijski procesi između Jadranske mikroploče i Euroazijske kontinentalne ploče uzrokovali su formiranje predgorskog bazena ispred uzdižućeg dinaridskog orogena, te je ranopaleogenska transgresija započela u različitim bazenima, odnosno u različitim dijelovima Vanjskih Dinarida, u različito vrijeme taloženjem naslaga bočatih laguna, koje su u literaturi poznate pod imenom Kozinske naslage. Istraživane naslage nalaze su u dijelu bazena poznatom kao sjevernodalmatinski bazen. Tijekom postojanja sjevernodalmatinskog dijela predgorskog bazena optimalni uvjeti za taloženje karbonatnih naslaga postignuti su u dva navrata, u ranom eocenu, kada su taloženi Foraminiferski vapnenci na širokom području forebulge sustava, te u srednjem eocenu kada su na padinama wedge-top bazena taloženi Gornji Numulitni vapnenci. Tijekom različitih vremenskih intervala, od ipra do bartona, na prostorima predgorskog bazena, pružanja SZ–JI, u okolišima nastalim na rampama, uz kontrolu sinsedimentacijske tektonike, taložen je nekoliko stotina metara debeo slijed naslaga u okolišima koje opisujemo kao Dinaridski sustav karbonatnih rampa. In the Northern Dalmatia area five outcrops of the lower Palaeogene carbonate deposits (Čikola I i II, Novigrad, Ostrovica i Grabova Glava) have been the subject of detailed sedimentological, micropaleontological and microfacies research. Furthermore, the biostratigraphic approach in combination with conventional facies analysis was used to reconstruct a range of carbonate depositional systems. Carbonate sedimentation took place in the inner, middle to outer ramp environments, where the dominant organisms were Large Benthic Foraminifera. The collision processes between the Adriatic continental microplate and Euroasia continental plate caused the formation of the Dinaridic foreland basin, developed during the Palaeogene in front of the uplifting mountain belt. Early Palaeogene transgression occurred in different times in different basins, as parts of the Outer Dinarides, firstly by the brackish lagoonal deposits known in literature as Kozina beds. Studied deposits are part of the Northern Dalmatian foreland basin and during its existence the conditions for the carbonate sedimentation were attained on two occasions. During the Early Eocene Foraminifera limestones were deposited on the vast forebulge area, and in the Middle Eocene Upper Nummulitic limestones deposited on the limbs of the wedge-top basins. During the different time intervals, spanning from the Ypresian to the Bartonian, in the NW–SE oriented foreland basin, carbonate ramps developed, controlled by synsedimentary tectonics, creating a couple hundreds of meters of deposits within environments described as Dinaridic Carbonate Ramps System.

Sjeverozapadno područje Dalmacije najvećim je dijelom prekriveno Prominskim naslagama koje su taložene u Dinarskom predgorskom (foreland) bazenu. Interpretiramo ih kao naslage "wedge-top" ili "piggyback" bazena čija je karakteristika jaka erozija vršnih uzdignutih dijelova reljefa. Erodirani materijal transportirao se riječnim putem i taložio se u nižim predjelima u kopnenom, prijelaznom i morskom okolišu. Tako su nastale i Prominske naslage u zaleđu dinarske orogene fronte. Nastale su izdizanjem Dinarida u eocenu i oligocenu u okviru alpske orogeneze. Promatranjem i korelacijom mnogobrojnih facijesa prominskih naslaga može se interpretirati njihov okoliš taloženja, ali i paleogeografski izgled područja. Northwestern area of Dalmatia is mostly covered by Promina beds that were generated in Dinaric foreland basin. We interprete them as "wedge-top" or "piggyback" layers of a basin that are characterized by a high erosion rates in the upper parts of a relief. Eroded material was transported by rivers and was sedimented in the lower parts of a relief in terrestrial and aquatic environments. That was also the way how did Promina beds developed in the background of a Dinaric orogen front. They were built in Eocene and Oligocene in an Alpine orogeny realm. With viewing and correlation of many sedimentary facies of Promina beds, we can interprete their sedimentary environment so as paleogeographical situation of an area.