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V okolici Srednje vasi pri Bohinju smo preučevali sestavo breč in kalkarenitov v zaporedju biancone apnencev. Starost zaporedja smo določili z radiolariji. V mezozoiku je bilo ozemlje del Blejskega jarka, ki se je nahajal na distalnem delu kontinentalnega roba Jadranske plošče in je bil od Dinarske karbonatne platforme bolj oddaljen kot Tolminski jarek. Kamnine Blejskega jarka torej pripadajo najbolj notranji dinarski coni, ohranjeni na območju Slovenije. Jursko zaporedje sestavljajo spodnjejurski apnenci z ehinodermi (hierlaški facies) ter srednje in zgornjejurski plastoviti radiolarijski roženci in glinavci. V spodnji kredi si sledijo biancone apnenci, menjavanje laporjev in glinavcev ter na vrhu siliciklastiti z ofiolitnim drobirjem in z olistoliti apnenca. Biancone apnenci so približno 40 m debela serija plastovitih pelagičnih apnencev z vmesnimi plastmi karbonatnih turbiditov. Preučevani profil je odkrit ob cesti, ki pelje od Studorja na Uskovnico. Spodnji del profila sestavljajo radiolarijski apnenci (strukturno "packstone") z gomolji in plastmi roženca, mestoma se v zaporedju pojavljajo tanke plasti laporja. Radiolarijska združba je značilna za spodnji del spodnje krede (berriasij do spodnji valanginij). Starost je bila določena po naslednjih vrstah: Archaeodictyomitra apiarium (Rüst), Cinguloturris cylindra Kemkin & Rudenko, Dicerosaturnalis dicranacanthos (Squinabol), Hiscocapsa pseudouterculus (Aita), Mirifusus minor Baumgartner, Pantanellium squinaboli (Tan), Pseudodictyomitra carpatica (Lozyniak), Ristola cretacea (Baumgartner) in Tethysetta boesii (Parona). V zgornjem delu profila prevladujejo karbonatne breče. Klasti so oglati litoklasti plitvovodnih apnencev tipa "grainstone", posamezni ooidi, odlomki apnenčevih alg, miliolidne foraminifere in drugi skeletni fragmenti različnih velikosti. Pogosti so tudi manjši klasti roženca in klasti pelagičnega apnenca s kalpionelami. Določili smo vrsto Calpionella alpina Lorenz, ki ima razpon od zgornjega tithonija do spodnjega valanginija. Osnova breč je mikrit, bogat z radiolariji. Starost platformnih karbonatov je bila določena z apnenčevo algo Clypeina jurassica Favre, ki je značilna za obdobje od zgornjega kimmeridgija do spodnjega berriasija. V vrhnjem delu profila se karbonatne breče menjavajo s kalkareniti. Izrazite so tudi gube, nastale s podmorskim plazenjem ("slump"). Ekstraklasti in karbonatni drobir nedvomno kažejo na platformni izvor presedimentiranih apnencev. Biancone apnenci so regionalno razširjen pelagični facies v spodnji kredi, vendar so drugje, npr. v Tolminskem jarku, sestavljeni izključno iz mikritnih apnencev in ne vsebujejo plasti breč ali kalkarenitov. Zato sklepamo, da Dinarska karbonatna platforma ni mogla biti izvorno področje plitvovodnih klastov v Blejskem jarku. Domnevamo, da je platformni material prihajal z nasprotne strani, to je s karbonatne platforme, ki je obstojala na bolj interni lokaciji, vendar se zaradi poznejše erozije in narivanja ni ohranila. Ta domnevna platforma se je lahko razvila na dvignjenem zaporedju pokrovov, ki so se formirali v zgodnji fazi narivanja notranjih dinarskih con na rob kontinenta. Približno enako stare izolirane karbonatne platforme s podobno genezo so bile opisane na več lokalitetah v Alpah, Dinaridih in Karpatih. Do sedaj sta najbolje dokumentirani karbonatna platforma Plassen (starost: oxfordij-kimmeridgij do berriasij) v Severnih apneniških Alpah in karbonatna platforma Kurbnesh (starost: kimmeridgij? do tithonij) v ofiolitni coni Mirdita v Albaniji. Znani, a manj raziskani so primeri zgornjejurskih grebenskih apnencev, ki diskordantno ležijo na ofiolitih v Vardarski coni v Srbiji in v gorovju Apuseni v Romuniji.

The field-trip deals with the eastern Southern Alps where the Southalpine and the Dinaric structures now overlap. In the Mesozoic times, this area belonged to the northeastern Adriatic continental margin facing the Meliata-Maliac-Vardar Ocean but was, on the other side, also close to the Alpine Tethys. Several paleogeographic units are differentiated in the area. The Bled Basin occupied the most distal position on the continental margin. This basin was characterized by deep-water sedimentation from the Norian onwards and by a relatively early onset of flysch-type sedimentation in the Valanginian-Hauterivian. The Julian High was a pelagic plateau that formed when the Triassic to Early Jurassic carbonate platform (the Julian Carbonate Platform) was dissected into blocks, subsided and drowned. The Bovec Basin evolved during the Pliensbachian to the Bajocian on a more deeply subsided block of the same platform. The Tolmin Basin existed between the Julian High and the stable Dinaric Carbonate Platform from the Triassic to the end of the Cretaceous. Based on the stratigraphic record, the Norian to Albian evolution of these sedimentary basins is divided in the following stages: 1) In the Norian and Rhaetian, the lagoonal Dachstein limestone and marginal coral reefs were deposited on the Julian Carbonate Platform. Limestones and dolomites with chert accumulated in the Bled and Tolmin basins. These deeper-water deposits include fault-derived coarse-grained breccias. Until the Pliensbachian, both basins were characterized by resedimented carbonates shed from the coeval Julian Carbonate Platform. 2) The main subsidence phase occurred in the Pliensbachian and is documented by a shift to distal-shelf environment and the first generation of neptunian dikes on the subsided platform, coarse-grained breccia in the Bled Basin, and a change in composition of resedimented limestones (crinoidal limestones start to prevail) in the Tolmin Basin. The Toarcian was a tectonically quiet period. Clay-rich deposits including Early Toarcian black shales are preserved in the Bovec and Tolmin basins. 3) The subsequent subsidence phase in the Bajocian caused further deepening of the entire area. Until the late Early Tithonian condensed Rosso Ammonitico type limestones accumulated on the Julian High, whereas the surrounding basins were characterized by radiolarian cherts and shales. Carbonate gravity-flow deposits, this time sourced from the Dinaric Carbonate Platform, were common in the Tolmin and Bovec basins, but absent in the Bled Basin. 4) In the Late Tithonian, the Biancone limestone started to accumulate in all paleogeographic units of the area. The Berriasian limestone breccias in the Bled Basin provide evidence of an isolated carbonate platform that, after the ophiolite emplacement and uplift, formed in more internal Dinaric units and was later eroded. The overlying Valanginian-Hauterivian turbidites with clastic admixtures document the evolution of the Bled Basin into a typical foreland basin. 5) Around the Aptian-Albian boundary, the Early Cretaceous orogeny was intensified and caused a renewed subsidence (associated with an erosional event) in more external paleogeographic units. Coarse-grained polymictic breccias accumulated in the Tolmin Basin. The second generation of deep breccia-filled neptunian dikes on the Julian High was most probably also related to this tectonic event.

The Guevgueli Complex, located in the border region of Republic of Macedonia and Greece, is one of the largest ophiolite complexes in the Dinarides. More specifically, it is attributed to the Eastern Vardar Ophiolitic Unit, which was obducted eastward onto the continental margin of Eurasia (Schmid et al., 2008). The Guevgueli ophiolite sequence is composed of pillow basalt and gabbro, but no peridotites are present. Granitoid intrusions (Fanos Granite) cut through ophiolite sequence and the crystalline basement. In places, the ophiolite sequence is covered by Upper Jurassic limestones. The Guevgueli Ophiolite Complex has been regarded as derived from a Middle – Late Jurassic backarc basin, which opened along the Eurasia continental margin (Saccani et al., 2008). Age constraints for the evolution of this ophiolite complex are still rare. The intrusion of the Fanos Granite has been dated with U–Pb zircon dating to 158 ± 1 Ma (Anders et al., 2005), i.e. approximately to the middle Oxfordian. Radiolarian sediments in association with ophiolites have so far been dated only at one locality in Greece and were also assigned to the Oxfordian (Danelian et al., 1996). However, the contact between these sediments and the basalts is probably tectonic, not stratigraphic. Our research was carried out in the area of Demir Kapija, Republic of Macedonia, where basalts and overlying carbonates are well exposed. During mapping, four localities with radiolarian cherts in direct stratigraphic contact with pillow lavas were found. All samples contained relatively well preserved radiolarian assemblages that include the following species: Cinguloturris carpatica Dumitrica, Eucyrtidiellum ptyctum (Riedel & Sanfilippo), Striatojaponocapsa naradaniensis (Matsuoka), Transhsuum brevicostatum (Ožvoldova), and Transhsuum maxwelli (Pesagno). This assemblage is characteristic of the late Bathonian – early Callovian (UA Zone 7). The sequence overlying basalts starts with coarse-grained conglomerates which contain clasts of limestones and various igneous, predominantly granitoid rocks in a reddish silty matrix. Remains of pelagic crinoid Saccocoma, classically attributed to the Kimmeridgian and Lower Tithonian, were found in limestone clasts. The conglomerates are overlain by a 250 to 300 m thick carbonate succession. The lower part, which is about 100 m thick, consists of marly limestones, calcarenites and breccias. Open marine fauna (e.g. aptychi) and algae of lagoonal facies (e.g. Clypeina jurassica Favre) were found in the calcarenites. The upper part of the succession consists of thick bedded and massive bioclastic limestone, and dolomitic limestone that represent typical platform facies. The following conclusions can be drawn from our preliminary results: 1) The seafloor spreading in the Guevgueli backarc basin was active in the late Bathonian – early Callovian. The backarck basin was short-living, as suggested by the Oxfordian age of the granitoid intrusions that cut the ophiolite sequence. The Guevgueli Complex is younger than ophiolite complexes that were emplaced westward onto the Adriatic margin. The sedimentary cover of the Vourinos ophiolites, for example, is assigned to the latest Bajocian – early Bathonian (UA Zone 5, Chiari et al., 2003). 2) The carbonate platform on top of the ophiolitic nappe stack formed gradually, since it is evident that the lower part of the carbonate succession was deposited in relatively deep water. Several examples of carbonate platforms associated with ophiolites exist in the Alpine – Dinaride – Carpathian orogenic system and it is generally thought that they formed as isolated platforms when ophiolites were uplifted to shallow water depths. In our case it is more likely that the platform evolved when a pre-existing platform (e.g. the Getic Carbonate Platform, now preserved in eastern Serbia, Romania and Bulgaria) prograded over the European continental margin.

The Julian Alps in NW Slovenia preserve remnants of several paleogeographic units of the northeastern Adriatic continental margin. Among these units, the Bled Basin had the most distal position on the continental margin. This paleogeographic location is assumed because the flysch-type sedimentation in the Bled Basin started in the Early Cretaceous but significantly later, in the Campanian to Maastrichtian, in more proximal basins of the Julian Alps. Here we present preliminary results on sedimentology and biostratigraphy of the Bled Basin. The Lower Jurassic succession, overlying Norian-Rhaetian limestones with chert, is characterized by bedded, often cherty limestones with echinoderms that laterally and vertically pass into massive oolitic limestone. The uppermost part consists of several beds of coarse-grained carbonate breccia that contain large limestone and chert clasts, and also irregularly shaped folded layers of chert. Based on the foraminifer Involutina liassica (Jones) found in breccia clasts and regional stratigraphic correlations, the Pliensbachian is the most probable age of this breccia. The overlying lithostratigraphic unit comprises radiolarian cherts and shales. The lower part consists of several meters thick slumped chert beds with almost no shale. The content of shale significantly increases higher up in the succession. Chert beds are generally laminated. In places, normal grading and channel structures clearly indicate that the chert beds were deposited as low-density turbidites. Radiolarian assemblages from cherts give age constraints from the middle Bathonian-early Callovian to the late Kimmeridgian-early Tithonian, suggesting a significant stratigraphic gap between this unit and the underlying breccia. In the upper part, cherts and shales alternate with marly limestone and are overlain by laminated limestone, which passes into typical Biancone limestone. Radiolarians from the uppermost beds of the Biancone limestone indicate a latest Tithonian to earliest Berriasian age. The Biancone limestone is overlain by gravity-flow deposits composed mostly of shallow-water limestone clasts and isolated bioclasts (e.g. Clypeina jurassica Favre) derived from a penecontemporaneous carbonate platform. The overlying succession starts with siliceous limestone with a significant proportion of marl and then passes into mixed siliciclastic-carbonate turbidites. These turbidites represent the oldest synorogenic deposits in the area. The first mixed turbidites are dated with radiolarians as Berriasian to early Valanginian. Higher up in the succession Valanginian-Hauterivian calcareous nannofossils were found. During the extensional phases in the Late Triassic and Early Jurassic the Bled Basin was a relatively deep basin as evidenced by bedded limestones containing chert nodules and layers. This tectonic activity culminated in the Pliensbachian subsidence pulse, which was responsible for the deposition of the coarse-grained breccia. During the next major subsidence phase in the Bajocian, the Bled Basin evolved into a true deep-water basin with radiolarian cherts as back-ground sediments. Since the Bled Basin was facing the Meliata-Maliac-Vardar Ocean, which was already in a convergent regime in the Middle Jurassic, tectonic down-warping is the likely explanation for this subsidence phase. The Berriasian limestone breccia in the Bled Basin provides evidence of an isolated carbonate platform that, after the ophiolite emplacement and uplift, formed in more internal Dinaric units and was later eroded. The overlying turbidites with clastic admixtures document the evolution of the Bled Basin into a typical foreland basin.

Carbonate gravity-flow deposits at Srednja vas near Bohinj have been studied for radiolarian dating and composition of resedimented limestones. Paleogeographically, the area was part of the Bled Trough, which had a relativelly distal position on the Adriatic continental margin and was rather far from the stable Dinaric Carbonate Platform. The Jurassic to Lower Cretaceous succession of the Bled Trough consists of: Lower Jurassic limestone with echinoderms (Hierlatz facies), Middle and Upper Jurassic bedded radiolarian cherts and shales, Biancone limestone, alternation of marls and shales, and finally siliciclastics with limestone olistoliths and ophiolite debris. This research is focused on the Biancone limestone, an approximately 40 m thick series of well bedded pelagic limestone, which includes intercalations of resedimented carbonates. The lower part of the studied section consists of radiolarian packstone with chert nodules and layers, and in places contains thin interlayers of marl. Radiolarian assemblages from these beds indicate an Early Cretaceous age (Berriasian – early Valanginian). The age assignment is based on the following species: Archaeodictyomitra apiarium (Rüst), Cinguloturris cylindra Kemkin & Rudenko, Dicerosaturnalis dicranacanthos (Squinabol), Hiscocapsa pseudouterculus (Aita), Mirifusus minor Baumgartner, Pantanellium squinaboli (Tan), Pseudodictyomitra carpatica (Lozyniak), Ristola cretacea (Baumgartner), and Tethysetta boesii (Parona). The upper part consists mainly of carbonate breccias. Microfacies analyses showed angular to subangular shallow-water grainstone lithoclasts, ooid grains, fragments of calcareous algae, miliolid foraminifera and various other skeletal fragments of different size. Clasts of pelagic limestone are also present and contain Calpionella alpina Lorenz whose range is late Tithonian to earliest Valanginian. The matrix of breccias is radiolarian-rich lime mudstone. The age of the platform carbonates is determined on the basis of calcareous alga Clypeina jurassica Favre which is characteristic of late Kimmeridgian to earliest Berriasian. In the uppermost part, carbonate breccias alternate with calcarenites. Slump folds are common. Extraclasts and calcareous debris undoubtedly prove a platform origin of resedimented limestone. The Biancone limestone of the Tolmin Trough, which occupied an intermediate position between the Dinaric Carbonate Platform and the Bled Trough, consists of micrite without resedimented limestones. Therefore we conclude that the Dinaric Carbonate Platform could not be the source of shallow-water carbonates in the Bled Trough. We believe that these breccias represent evidence of a carbonate platform which must have been located more internally but is now not preserved. This inferred platform may have developed on top of a nappe stack, which formed during the early emplacement of the internal Dinaric units onto the continental margin. Genetically similar isolated carbonate platforms of more or less the same age are known from several localities in the Alpine – Dinaride – Carpathian mountain belt. The Oxfordian/Kimmeridgian to Berriasian Plassen Carbonate Platform of the Northern Calcareous Alps in Austria and the Kimmeridgian? – Tithonian Kurbnesh Carbonate Platform from the Mirdita Ophiolite Zone in Albania have so far been the best documented. Other examples include Upper Jurassic reef limestones unconformably overlying the Vardar ophiolites in Serbia and the South Apuseni ophiolites in Romania.

Carbonate gravity-flow deposits at Srednja vas near Bohinj have been studied for radiolarian dating and composition of resedimented limestones. Paleogeographically, the area was part of the Bled Trough, which was located NE of the Tolmin Trough and thus relatively distal with respect to the Dinaric Carbonate Platform. The Jurassic to Lower Cretaceous succession of the Bled Trough consists of: Lower Jurassic limestone with echinoderms (Hierlatz facies), Middle and Upper Jurassic bedded radiolarian cherts and shales, Biancone limestone, alternation of marls and shales, and finally siliciclastics with limestone olistoliths and ophiolite debris. This research is focused on the Biancone limestone, an approximately 40 m thick series of well bedded pelagic limestone, which includes intercalations of resedimented carbonates. The lower part of the studied section consists of radiolarian packstone with chert nodules and layers, and in places contains thin interlayers of marl. Radiolarian assemblages from these beds indicate an Early Cretaceous age (Berriasian – early Valanginian). The upper part consists mainly of carbonate breccias. Microfacies analyses showed angular to subangular shallow-water grainstone lithoclasts, ooid grains, fragments of calcareous algae, miliolid foraminifera and various other skeletal fragments of different size. Clasts of pelagic limestone are also present and contain Calpionella alpina LORENZ whose range is late Tithonian to earliest Valanginian. The matrix of breccias is radiolarian-rich lime mudstone. The age of the platform carbonates is determined on the basis of calcareous alga Clypeina jurassica FAVRE which is characteristic of late Kimmeridgian to earliest Berriasian. In the uppermost part, carbonate breccias alternate with calcarenites. Slump folds are common. Extraclasts and calcareous debris undoubtedly prove a platform origin of resedimented limestone. The Biancone limestone of the Tolmin Trough, which occupied an intermediate position between the Dinaric Carbonate Platform and the Bled Trough, consists of micrite without resedimented limestones. Therefore we conclude that the Dinaric Carbonate Platform could not be the source of shallow-water carbonates in the Bled Trough. We believe that these breccias represent evidence of a carbonate platform which must have been located more internally but is now not preserved. This inferred platform may have developed on top of a nappe stack, which formed during the early emplacement of the internal Dinaric units onto the continental margin. Genetically similar isolated carbonate platforms of more or less the same age are known from several localities in the Alpine – Dinaride – Carpathian mountain belt. GAWLICK & SCHLAGINTWEIT (2006) described the Plassen Carbonate Platform which developed above Callovian to Tithonian basinal deposits of the Northern Calcareous Alps. SCHLAGINTWEIT et al. (2008) analysed clasts in mass-flow deposits to reconstruct a completely eroded Kimmeridgian? – Tithonian Kurbnesh Carbonate Platform from the Mirdita Ophiolite Zone in Albania. Other examples include Upper Jurassic reef limestones unconformably overlying the Vardar ophiolites in Serbia and the South Apuseni ophiolites in Romania (SCHMID et al., 2008).

Na vzhodni obali Istre v bližini vasi Koromačno je morska erozija razkrila več kilometrov dolg profil, kjer se na meji med svetlo sivimi santonijskmi apnenci in spodnje eocenskimi apnenci Liburnijske formacije pojavljajo do več metrov debela telesa breč in boksitno-karbonatnih peščenjakov.

Smernice Evropske skupnosti (DIRECTIVE 2000/60/EC) opredeljujejo telesa podzemne vode (body of groundwater) kot ločljivo prostornino vode v vodonosniku ali sistemu vodonosnikov. Vsaka članica ES mora opredeliti vsa telesa podzemne vode, ki se že uporabljajo ali pa so v prihodnosti namenjena za izkoriščanje pitne vode. Posebno podrobno je potrebno opredeliti obmejna telesa podzemne vode, to je tista, kjer se podzemna voda v vodonosnikih pretaka z ene strani meje na drugo. V letu 2000/2001 so bile opravljene skupne hrvaško slovenske raziskave na območju med Tržaškim in Kvarnerskim zalivom na podlagi, katerih smo skupno definirali vodnosne sisteme, ki se raztezajo na tem območju z ene strani državne meje na drugo. V okviru teh skupnih koordiniranih raziskav je bila napravljena poenotena hidrogeološka karat v skladu z mednarodnimi standardi, določene so bile prekomejne razvodnice in odprta vprašanja glede le-teh, vzpostavljena sta bila skupni geoinformacijski sistem ter mreža vzorčevanj podzemnih vod na reprezentativnih izvirih za ugotavljanje njihovega izvora in kakovosti, izveden pa je bil še sledilni poskus na območju mesta Buje in izviri Bužini in Gabrijeli. Vodonosni sistemi na tem obmejnem območju so izrednega pomena za oskrbo z vodo tudi večjih mest kot sta Reka in Koper. Za ohranjanje in optimalno izkoriščanje teh vodonosnikov, kjer so lahko območja napajanja v eni državi, točke izkoriščanja pa v drugi, so nujne vzajemne raziskave strokovnjakov na obeh straneh meje.

The Post-Forum Study Tour following the 4th World Landslide Forum 2017 in Ljubljana (Slovenia) focuses on the variety of landslide forms in Slovenia and its immediate NW surroundings, and the best-known examples of devastating landslides induced by rainfall or earthquakes. They differ in complexity of the both surrounding area and of the particular geological, structural and geotechnical features. Many of the landslides of the Study Tour are characterized by huge volumes and high velocity at the time of activation or development in the debris flow. In addition, to the damage to buildings, the lives of hundreds of people are also endangered; human casualties occur. On the first day, we will observe complex Pleistocene to recent landslides related to the Mesozoic carbonates thrust over folded and tectonically fractured Tertiary siliciclastic flysch in the Vipava Valley (SW Slovenia), serving as the main passage between the Friulian lowland and central Slovenia, and thus also an important corridor connecting Northern Italy to Central Europe. A combination of unfavourable geological conditions and intense short or prolonged rainfall periods leads to the formation of different types of complex landslides, from large-scale deep-seated rotational and translational slides to shallow landslides, slumps and sediment gravity flows in the form of debris or mudflows. The second day of the study tour will be held in the Soča River Valley located in NW Slovenia close to the border with Italy, where the most catastrophic Stože landslide in Slovenia recently caused the deaths of seven people, and the nearby Strug landslide, which is a combination of rockfall, landslide and debris flow. The final day of the Post-Forum Study Tour will start in the Valcanale Valley located across the border between Slovenia and Italy, severely affected by a debris flow in August 2003. The flow caused the deaths of two people, damaged 260 buildings; large amounts of deposits blocked the A23 Highway, covering both lanes. In Carinthia (Austria), about 25 km west of Villach, the Dobrač/Dobratsch multiple scarps of prehistoric and historic rockslides will be observed. Dobratsch is a massive mountain ridge with a length of 17 km and a width of 6 km, characterized by steep rocky walls. The 3-day study tour will conclude with a presentation of the Potoška planina landslide, a slide whose lower part may eventually generate a debris flow and therefore represents a hazard for the inhabitants and for the infrastructure within or near the village of Koroška Bela.

The Paleocene-Eocene thermal maximum represents one of the most rapid and extreme warming events in the Cenozoic. Shallow-water stratigraphic sections from the Adriatic carbonate platform offer a rare opportunity to learn about the nature of Paleocene-Eocene thermal maximum and the effects on shallow-water ecosystems. We use carbon and oxygen isotope stratigraphy, in conjunction with detailed larger benthic foraminiferal biostratigraphy, to establish a high-resolution paleoclimatic record for the Paleocene-Eocene thermal maximum. A prominent negative excursion in delta C-13 curves of bulk-rock (similar to 1 parts per thousand-3 parts per thousand), matrix (similar to 4 parts per thousand), and foraminifera (similar to 6 parts per thousand) is interpreted as the carbon isotope excursion during the Paleocene-Eocene thermal maximum. The strongly C-13-depleted delta(1)d(3)C record of our shallow-marine carbonates compared to open-marine records could result from organic matter oxidation, suggesting intensified weathering, runoff, and organic matter flux. The Ilerdian larger benthie foraminiferal turnover is documented in detail based on high-resolution correlation with the carbon isotopic excursion. The turnover is described as a two-step process, with the first step (early Ilerdian) marked by a rapid diversification of small alveolinids and nummulitids with weak adult dimorphism, possibly as adaptations to fluctuating Paleocene-Eocene thermal maximum nutrient levels, and a second step (middle Ilerdian) characterized by a further specific diversification, increase of shell size, and well-developed adult dimorphism. Within an evolutionary scheme controlled by long-term biological processes, we argue that high seawater temperatures could have stimulated the early Ilerdian rapid specific diversification. Together, these data help elucidate the effects of global warming and associated feedbacks in shallow-water ecosystems, and by inference, could serve as an assessment analog for future changes.

The Vis Island belongs to the group of the Middle Dalmatian islands. It comprises an area of about 90, 2 km2. Morphologically, three belts of highlands and two depressions with karst poljes are significantly marked. The highest point on the island is Hum with 587 m a.s.l. Island’ s water supply is organized from the water-supply station “ Korita” , situated in the central part of island, in the tectonically formed depression. On the Vis Island there are two additional captured objects: well K-1 above the Komiža town and the spring “ Pizdica” . The most important hydrogeological role on the island have two hydrogeological barriers, one in the Komiža Bay, completely made of impermeable magmatic and clastic rocks, and another one, recently recognized relative barrier in the area of Dračevo, Plisko and Velo poljes. Due to the fact that the island karst aquifer is in permanent dynamic relation with seawater, classical geologic, structural and hydrogeologic investigations have been extended with application of hydrogeochemical methods taking into account the natural chemical tracer content of groundwater and its variations in different hydrologic and vegetation conditions. Precipitation regime in this area is very unfavorable with regard to the recharging of island’ s aquifer because dry periods are usually very long. During the summer tourist season, when the number of inhabitants and fresh water consumption considerably increase, amounts of island’ s groundwater suitable for water supply and irrigation rapidly decrease. Sometimes, insufficient quantity of fresh water on the Vis Island causes restrictions. Concerning the development of tourist potential and present agricultural activities, summer lack of water is a seriously restrictive factor. Some results of performed hydrogeological study, important as a basis for island’ s fresh water potential assessment, will be presented.

Proučevano ozemlje obsega Medvednico, Kalnik, Ivanščico in Žumberak v zahodnem delu Panonske kotline. Triasno pelagično zaporedje na Medvednici in Kalniku je značilno za oceanski bazen, na Ivanščici in na Žumberku pa za kontinentalni rob. Na severozahodnem delu Medvednice in na Kalniku je odkrita nepolpona ofiolitna sekvenca, ki jo sestavljajo gabro, bazalt in plastnati radiolarijski roženci, med katerimi se lakotno pojavljajo plasti tufskih glinencev. Z radiolariji in konodonti smo na različitih lokalitetah ugotovili starosti od zgornjega anizija do spodnjega norija. Zgornjeanizijski konodonti so bili najdeni v apnencih med blazinastimi lavami tipa MORB. Spodnji ladinij, zgornji ladinij in zgornji karnij smo določili v radiolarijskih rožencih, ki se pojavljajo med različitimi novoji blazinastih bazaltov, spodnji norij pa je bil določen v rožencih nad blazinastimi lavami. Triasne kamnine tega območja so del magmatsko-sedimentnega (akrecijskega) kompleksa, ki vključuje tudi srednjejurske rožence in konglomerate s klasti bazalta. Domnevamo, da je območje severozahodne Medvednice in Kalnika pripadalo Meliatsko-Hallstattskemu oceanu. Srednjetriasne vulkanske kamnine na Ivanščici so bazalte in andezitni bazalti, vezani na sedimentno podlogo (navadno dolomit). Piroklastiti so pgosti. Podrobneje smo pročili sedimentno zaporedje, ki kaže oster prehod med platformnimi in globljemorskimi kamninami. Profil se začne z masivnim dolomitom, na katerem leži nekaj deset metrov debela karbonatna breča. Vezivo v spodnjem delu breče je pelagični apnenec, v zgornjem delu pa prevladuje tufski material. Na breči ležijo plastnati radiolarijski roženci z vmesnimi plastmi tufskih glinencev. V najnižjih plasteh radiolarijskih rožencev smo določili spodnjeladinijsko starost. Pelagično trijasno zaporedje na Žumberku sestavljajo radioalrijski roženci in apnenci s palstmi tufa in tufskega meljevca ali rdeči gomoljasti apnenci z roženci. Baza pelagičnega zaporedja je zgornjoanizijske starosti. Skupna debelina pelagičkih plasti je do 50 m, pod in nad njimi so plastnati dolomiti. V zgornjem aniziju se je začel oceanski bazen odpirati, hkrati pa je ekstenzija povzročila hitro subsudenco kontinentalnega roba. Glede na sočasno pojavljanje bazaltov in andezitnih bazaltov na kontinentalnem robu, MOR bazaltov v oceanskem bazenu ter tufov in tufskih glinavcev v obeh sedimentacijskih prostorih lahko sklepamo, da se je oceansko območje Medvednice in Kalnika odprlo kot back-arc bazen. Pozneje, verjetno proti kocu ladinija ali na začetku karnija, je karbonatna platforma progradirala čez robne bazene, v oceanskih predelih pa se je globljemorska sedimentacija nadaljevala še v zgornjem triasu in v juri.

For the purpose of the Geochemical map of the Republic of Croatia in the year 1998 the soil samples at a depth down to 25 cm were collected in a quadratic grid 5x5 km. At the same time the soil profiles in the alluvial sediments of the Sava and Drava rivers were sampled. The analytical work (ICP-AES and FAAS for Hg) was performed on the granulometric fraction

Preliminary studies of surface sediments (f < 63 ľm) from Voglajna and Savinja rivers are reported and discussed. XRD data showed that river sediments predominantly consist of quartz. Muscovite was found in all samples as minor mineral. Feldspars were detected in sediments of Voglajna. Calcite was found in Voglajna near Šentjur and Štore. Calcite and dolomite were found in sediments of Savinja. From about 50 elements determined by ICP-MS method, concentration of iron predominates (2.8-5.6%). It is highest in Voglajna at Štore. From microelements the highest concentrations of Cr, Ni, Cu, Mo, Sb, W and Pb were found in the same sediment. Concentration of Al and K are similar in all samples. Ca and Mg are higher in Savinja, than in Voglajna. Zn, Cd, Ag and Au show the highest concentrations in sediments of Savinja at Tremerje, below Celje. Most of trace elements are in good correlation with iron. Iron minerals could not be well determined by XRD. Further characterization of iron in sediments was performed by 57Fe Mössbauer spectroscopy at room temperature. Spectra were fitted with two doublets showing relatively similar isomer shifts and quadrupole parameters. The ratio Fe(III)/Fe(II) decreases downstream Voglajna river. In addition to the presence of two doublets, two magnetic sextets are present in the sediment of Voglajna at Štore, suggesting the presence of Fe3O4 in minor quantity. The work is in progress to determine iron containing minerals in these rivers.