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On the NW part of the Paleogene Adriatic Carbonate Platform (PgAd CP), beds from Maastrichtian to late Bartonian were deposited. The sedimentary succession consists of limestone and flysch. Previous investigations confirm the ages from SBZ 1 to SBZ 15 and planktonic zones from P1b-c to E 13. Regarding the Cretaceous paleogeographic basement drowning, three distinct sedimentary belts could be distinguished, delimited by faults or barriers of various origins. The purpose of the present contribution is the temporal definition based on foraminiferal assemblages. In each belt, the youngest assemblage of the shallow-water platform and the oldest assemblage of the deeper-water clastic deposits were determined. On the territory of PgAd CP this is the new attempt at defining the geologic boundaries by the successive appearance of benthic and planktonic foraminiferal groups. The entire Paleogene sedimentary complex lies in the footwall of the Frontal Zone of External Dinaric Thrust belt (Trnovo thrust series), which was related to L. Placer's "Hypothetic fault structure in the Adriatic-Dinaric Mesozoic Carbonate Platform in the continuation of the Budva Trough". After the last rotation of the entire Adria block, at the end of the Miocene and in the latest Pliocene, tectogenetic units formed, arranged from NE towards SW. 1) The Budva Trough with hemipelagic sediments at the Paleocene/Eocene boundary (P 5 - Subbotina velascoensis, Morozovella acuta, M. occlusa) and turbiditic deposits in the basin at the contact with the Dinarides from Goriška brda, Vipava/Pivka basin to Ilirska Bistrica, with numerous nummulites and Alveolina violae ; BiosZ 1. 2) Southwards follows the Kras – Brkini and Vinodol syncline with flora and fauna in lagoonal, shallow marine sediments from the K/T boundary to the Ilerdian/Cuisian passage (SBZ 8, 9). Typical are Alveolina triestina, A. brassica, A. montanarii, (SBZ 10) A. canavarii, A. schwageri. Among planktonic foraminifera appear (P 6/7, E 4/5) Acarinina pseudotopilensis, Morozovella subbotinae ; BiosZ 2. 3) Southward a narrow belt of limestones occurs in Ćićarija Imbricated zone with the same Paleocene and Ilerdian foraminifera, from Rosandra river to Voz peninsula (Island of Krk). Sedimentation continues without interruption from lower to upper Cuisian, extending in middle Cuisan southwards towards Istria. Larger foraminifera (SBZ 12) include the lineage of A. histrica with A. rakoveci, A. cuspidata. Marly and flysch beds of the lower Lutetian are characterized by (P 9/10, E 7/8) A. praetopilensis, A. bullbrooki, and M. aragonensis ; BiosZ 3/1, 2. 4) A parallel zone in the south, the imbricated Adria, is synchronously limited by Istrian dryland, the Adria basin open to east, and the Venetian basin to west. During the middle Cuisian a first transgression covers the land with lagoons, coal seams and bauxite pits. Deposits (SBZ 13, 14) of Alveolina nummulitic limestones follow the lineage of A. levantina, A. elliptica nuttalli, A. frumentiformis, Glomalveolina delicatissima, which pass into the youngest beds on the platform margin to nummulitic, assilina and orthofragmina limestones. They are overlain by Transitional beds and later by flysch, containing (E /10) Turborotalia possagnoensis and Hantkenina dumblei ; BiosZ 4/1, 2, known as the Dalmatian zone. 5) The boreholes of Istra more 5, 4 and 3 are located along the eastern rim of the Venetian basin. The hemipelagic sediments of Middle Eocene contain Morozovelloides crassatus, Acarinina mcgowrani, and in the Upper Eocene Turborotalia cocoaensis ; BiosZ 5. Fauna determined at the transition from the platform to flysch within the NW Paleogene tectogenetic units indicates a separated realm: a shallow carbonate platform with intraplatform barriers in the form of the archipelago extended across Friuli to the Trento platform, on the Lessini shelf, over the Venetian basin.

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 Paleogene (Early Ypresian, SBZ 11 to Bartonian, SBZ 17) carbonates originated on the Adriatic carbonate platform are dominated by various larger foraminiferal facies with subordinate coralline red algae facies. Foraminiferal tests (studied from standard thin-sections) show evidences of mechanical, biological or chemical breakdown with intensity that varies between foraminiferal groups and depositional settings along the shelf gradient (from proximal restricted/lagoonal to outer ramp settings). Effects observed include breakage, cutting of test edges (poles), removal of surface layering, chamber-space infillings, borings, encrustation, corrosion, pitting and their occurrences vary from sporadic to very common across the groups. Breakages ranging from damage to the terminal chamber/whorl to disintegration into sandand fine-size fragments are recorded within larger benthic foraminiferal tests in alveolinid-, nummulitid- and orthophragminid-dominated facies. Partially broken tests are most common in alveolinids. The co-occurrence of wide size range of clasts and unequal preservation of alveolinid tests attest to high- to moderate-energy settings, with possible post-mortem reworking (bombardment with sand-sized grains including more persistent nummulitid tests) within a short distance transport. Bioerosion traces in alveolinids are present in forms that were post-mortem transported over a greater distance and settled down in lower energy environments (mid to outer ramp). The mid-outer ramp environments characterize a predominance of rotaliid foraminifera over miliolids. Nummulites tests show a number of mechanical damages (cutting of tests edges, exfoliation of the youngest whorls, broken tests) as result of post-mortem seaward transportation and/or predation. Coralline red algae are significant biotic constituent in Nummulitic packstones to wackestones, and multilayer algal encrustation stands out as the most common feature. The post-depositional alternations consist of filling the pore spaces by micrite mud or by sparite, of redistribution of the tests by transport and/or by bioturbation. The upper-most part of the Eocene shallow-water carbonate succession is represented by Orthophragminae-bearing limestones (ranging in age from the Lutetian to Bartonian). They are mainly composed of orthophragminid and nummulitid tests spread in mud matrix, the former with abundant traces of bioerosion. A statistical analysis of affected specimens reveals that 10% of them are with boring marks. These non–randomly distributed traces point out to the predators or parasites responsible for leaving them, because drilling attacks are size selective and a position of traces within the test suggesting that they were made to gain access to the inside of the host. The occurrence of traces was controlled by environmental parameters such as low sedimentation rate, mesotrophication, lower photic zones and low energy, parameters that characterize outer ramp settings. As subordinate features, glauconitic infillings are recorded in some chambers spaces, as well as mechanical damages of tests (accompanied with the extensive micritic envelope), altogether suggesting the possible post-mortem transport of from shallower part of ramp towards the upper slope.

Due to specific, restricted shallow-water environments that inhabited and relatively low abundances, the Paleogene conical foraminifera with agglutinated shells among larger benthic foraminifera are relatively unknown. They can be considered as a powerful tool in recognition of transgressions or shallowing upward sequences within regression. The assemblage passed through dramatic changes in composition and reduction in diversity when co-occurred with larger, complex miliolids. Up to now, 11 genera and 18 species are described from sediments deposited in Tethyan bioprovinces, in area stretching from Atlantic to Indo Pacific region. The appearance of diversified association of conical foraminifera coincides with the Late Paleocene (Thanetian, SBZ 3 and 4). In northern Tethyan bioprovince (W Pyreneans and Paleogene Adriatic Carbonate Platform) 7 species are found, while in Corfu 4, 1 in E Turkey and 8 in Iran. On the southern margin, these foraminifera are found in Oman and Somalia. Contrary to the Ilerdian (Ypresian, SBZ 5 -9), when conical foraminifera were rare, in the Cuisian (Late Ypresian, SBZ 10, 11-12), for the second time, they became abundant and their association was highly diversified. Species were found in the Middle - Late Cuisian and Early Lutetian sediments deposited on Apulia platform (Trentinara Fm), Adriatic Carbonate Platform (Coskinolina liburnica Stache was known from 1875), in Afghanistan (4 species) and Pakistan (3 species), while their findings in Balucistan is considered very important for paleobiogeographic interpretation. Interestingly, being absent from the southern margin of Tethys till the Late Lutetian, they populated shallow-water settings of Tunisia, Egypt, Somalia and Iran (Jahrum Fm, with 7 taxa still not well defined) from the Late Lutetian to the Bartonian. The distinguished internal architecture of shell was recorded in the Paleocene specimens as variable (embryonic trochospiral coiling, marginal trough with radial exoskeletal partitions or undivided marginal chamber lumen) and stable elements (overall simple conical morphology, adult uniserial chamber arrangement, pillars in itraseptal space, septum as apertural face and agglutinated walls without internal structures). The decreasing in test size and number of structural elements are evolutionary trends of these foraminifera. According to published data (not recently updated), in Caribbean region conical foraminifera are known from upper part of the Early Eocene, and continued to live up to the Late Eocene. 6 genera (2 known from Tethys) and 9 species were found.

The Paleogene Adriatic carbonate platform (PgAdCP), existed within the Central Tethys (around 32 N palaeolatitude) from the Paleocene (Danian) to the late Middle Eocene (Bartonian). Its depositional history differs from the stages-pattern recognized in the platformal development in the Tethys region in the Pyrenees and Egypt (Scheibner & Speijer, 2007). In the Adriatic, the shallow-marine carbonate regime is composed of various facies types which are defined upon the larger benthic foraminiferal associations and sedimentary structures. These facies are grouped into and record temporal and spatial demise of certain ecological conditions. Sedimentation within each zone started with restricted, marginal marine, paralic and pallustrine carbonates, that we consider as the initially phase to gaining full marine conditions. Once the marine regime was obtained, the shallow-marine settings supported the development of diverse and abundant foraminiferal assemblages. The biota suggests that platform jumped into the third Tethyan stage even though sedimentation started in SBZ1 (Serra-Kiel et al., 1998) and lasted until SBZ 9 (BiosZ 2), in SBZ 2 until three main biosedimentary units, BiosZ 2 to BiosZ 4 (Drobne 2003, Drobne et al., 2008). These zones followed one upon another in a step-wise geographic pattern SBZ 12 (BiosZ 3), and in SBZ 11 to SBZ 14 (BiosZ 4). Interestingly, the second Tethyan stage, coralgal facies, is recorded within the NW margin in the BiosZ 2 area only. The characteristics that differ the Pg AdCP from others are: (1) a reduced species richness in the Paleocene succession (3 assilinid species in Paleocene) ; (2) less diversified Eocene foraminiferal assemblages (eg. 8 species of Nummulites in the early Eocene and 12 species from the middle Eocene, Pavlovec 2003 vs. 76 for early and 62 for middle Eocene, Less 1998), (3) absence of some taxa (Spiroclypeus sp., Heterostegina sp., Pellatispira sp.) ; (4) absence of encrusting foraminifera ; (5) the regularity in occurrences of certain larger foraminiferal groups: complex miliolids and agglutinated conical forminiferas characterize the beginning of platform regime, which gave way to alveolinids, orbitolitids and nummulitids assemblages, and which eventually were replaced by operculinids and orthophragminids ; (6) concurrence of BiosZ 3 with Alveolina histrica lineage and Alveolina levantina lineage with BiosZ 4.

Sediments deposited on the Paleogene Adriatic carbonate platform (PgAdCP), unique and distinguished paleogeographic unit, are today exposed along the eastern Adriatic coast in length of 600km and in width of 100-130 km. 90 identified alveolinid species ranging in age from the Ilerdian to the middle Lutetian, depict dynamic of their evolution with emphasis on the following: 1) great species diversity and great abundance in the middle Ilerdian (SBZ 8) followed by sharp declination in occurrences at the Ilerdian/Cuisian transition ; 2) diversity boom in the late Cuisian (SBZ 11, SBZ 12) and an abrupt decrease in species numbers after the early Lutetian. This pattern shows relationship between abundance/ diversity and global sea-level changes in TA events. The &raquo ; two peaks&laquo ; model in alveolinid occurrence is present, also, in &raquo ; Mediterranean assemblage&laquo ; in Pyrenean and within the middle Cuisian association at different Mediterranean areas. Based on studies of numerous section on the PgAdCP, biosedimentary zones (BioZ 2, 3, 4) were determined, each zone characterized by its specific alveolinid associations. These zones distributed as belts, are stretching from the N Italy (Friuli) to the southeast to Montenegro. Alveolinid association served as base for paleogeographic maps of the PgAdCP from the Cretaceous/Paleogene boundary to Priabonian.

Paleocene and Eocene sediments, ranging from the basinal to shallow-water platform facies, occur scattered around the vast region between the Adriatic Sea and the Pannonian basin. In order to correlate carbonates and clastic sediments and interpret them paleogeographically, identification of tectonic units is needed. Diversity and abundance of microfossils (representatives of the most far north Tethyan biota), larger benthic foraminifera, dasycladaceans, and bivalves in particular are considered as a tool for reconstructing shallow-water paleoenvironmental regions. Paleoenvironmental and paleobathymetric data from the investigated formations, coupled with palinspastic reconstruction, provide new insights into pre-Miocene paleogeography of the area. The tectonic units, from north to south, made of Paleogene deposits are the following: Transdanubia and Bükk region are considered to be part of the Pannonian unit, Krappfeld area is of the Eastern Alps (ALCAPA, for the both units), localities along the Periadriatic Fault System partly belong to the Eastern Alps (those on the northern side) , partly (those placed south to the line) to the Southern Alps – Dinarides, the outcrops in the southern Pannonian basin are a part of Internal Dinarides, whereas the region made of sediments deposited on the Adriatic carbonate platform belongs to External Dinarides.

The study of larger miliolids from the Late Cretaceous (5 genera, 8 species) and Paleogene (6 genera, 39 species) illustrates geographic, temporal and species distribution in four (Caribbean, European Tethys, North African Tethys and Indopacific) bioprovinces from the middle to late Eocene (Drobne 2002, Drobne & Hottinger 2004). The Late Cretaceous rich faunal association from the south Pyrenean shows endemic character.The Late Cretaceous rich faunal association from the south Pyrenean shows endemic character. Following the K/T event, as a consequences of the Thanetian transgression over the northern and southern margins of Neo-Tethys and renovation of the shallow marine environments (from Pyrenean to the east to Turkey, Iran, Egypt to Oman, in the SBZ3-SBZ 6) a new space for larger miliolids opened. Larger miliolids which were able to occupy new free habitats began with their restoration in the terms of species richness and abundances (Periloculina slovenica, Idalina sinjarica, I. causae, Helenalveolina rahaghii n.sp., Pseudolacazina donatae, Lacazina blumenthali, L. gracilis). The second diversification event during the Cuisian (SBZ11) is recorded in the central (European) Tethys with appearance of new species (P. dalmatina, Fabularia n. sp.). Middle Eocene radiation (SBZ 13) had a worldwide character in dispersion of fabularids (F. zitelli population in Egypt, F. ovata in Paris basin, F. colei and F. guenteri in Caribbean). The latter ones are considered as pioneers species that crossed the Atlantic to the west, and would adapt and radiate into several species. The paleoecological conditions in the late Middle Eocene (SBZ 17) resulting in morphological and abundance disparities between NE France fabularids (the largest tests of F. compressa) and those from the Pyrenean and Caribbean (sporadic occurrences of small specimens, F. roselli and F. gr. gunteri-vaughani). The uniformly dispersion over the waste area, from Caribbean to New Guinea characterized Upper Eocene age (SBZ 19, SBZ 20). It appears that the major differences between larger miliolid fauna form northern ad southern Neo-Tethys margin is distribution of Lacazinella to the southern bioprovinces. The oldest specimens are known from the Ilerdian (partly SBZ 4 – SBZ 8) from Oman, Somalia and Yemen. The representatives of the genus re-appeared further to the east (Papua, New Guinea) in the Late Eocene. The circulation pattern within Austral- pacific zone (in accordance with tectonic movements – collision in “ island arc system” ) predestinated specialized Lacazinella wichmanni to become present all over the region (along with Llle. haigi n. sp), while Lacazina reicheli is restricted to Maluku islands (westwards to New Guinea). The presented data questioned the evolutionary relationship between Lacazina and Lacazinella and allow a consideration of existence of possible refugee habitat.

Based on palemagnetic results from 177 samples of Cretaceous and Paleogene age from Makarska, Hvar and Brač islands and Pelješac peninsula we conclude that the platform sediments in our study area suffered CCW rotation with respect to the present north.

The shallow carbonate platforms of the central Tethys, exemplified by the Adriatic platform, are particularly expressed to sealevel rise and fall corresponding to the sedimentary sequences of the Paleogene. These cycles, by their repetition, constitute a kind of natural experiment allowing us to test the behaviour of communities in on ecological gradient covering the uephotic zone. In this gradient, the communities of larger K-strategist foraminifera are substituted according to fixed rules: agglutinated conical forms appear first, are gradually replaced by porcelaneous forms, subsequently by nummulitids and assilinids and finally by discocyclinids and "operculinids".Thus, the euphotic zone can be subdivided into 4 depth subzones.