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A fundamental and interdisciplinary approach to investigate abrupt climate change enables us to obtain valuable data and interpret the dynamics of these changes. These data and their interpretation can form the basis for both comparing paleoclimate changes with modern ones and predicting the dynamics of these changes in the future. These insights can make it easier for humankind to adapt to changes that will affect all aspects of life on Earth. Because of the fast and unquestionable climate change and threats that have emerged, geologists have been trying, based on records in Quaternary sediments, to identify the process of change. The exploration is focused on loess/paleosoil sequences and the Đurđevac Sands in the Pannonian area (continental climate) and fluvioglacial sediments in the foothills of the Velebit Mt. and lake sediments from Lake Vrgorac in the Dinaric area (Mediterranean climate). Firstly, explorations of loess-paleosoil sequences revealed the existence of 14 cumulic horizons, which evolved just above well-developed paleosoils. They represent paleoclimate archives of the dynamics of 14 climate changes. The research is focused on analyzing cumulic horizons in NE Croatia, providing detailed descriptions of transitions from the warm to the glacial period in the Late Pleistocene. Next, the investigation of paleosoils and geomorphological/sedimentological features in the dunes of the Đurđevac Sands may help to determine the nature of the Pleistocene- Holocene transition in this area, as well as potential Holocene climate-related paleoenvironmental changes. Those terrestrial archives in the south of the Carpathian Basin provide insight into the magnitude, timing, and spatial variability of climate changes. In addition, fluvioglacial sediment successions in the foothill of the Velebit Mt. are crucial for describing abrupt climate change during the Late Pleistocene, as it will reveal the magnitude, timing, and spatial variability of climatic transitions and correlate them with transitions in a continental climate as based on the other archives outlined above. Finally, the depositional environments and sediment facies found in Vrgoračko polje are considered to represent a typical Quaternary lacustrine sedimentation pattern for other Dinaric karst fields in a Mediterranean climate. The dynamics of all mentioned facies transitions in all proposed sections are a consequence of past climate change. The specific geological and pedological diversity, geographical position, geomorphology and climate diversity of Croatia enable the parallel high- resolution study of the development of abrupt climate changes at locations only 300 km apart. This research will improve our understanding of the spatial extent and differences in the occurrence of paleoclimatic events in the Pannonian and Dinaric areas. That will yield insight into eolian-fluvioglacial-lacustrine teleconnections in SE Europe. In turn, this forms the basis for supraregional correlations with the European Sand Belt (NW Europe) and the Adriatic Sea.

The Carpathian-Pannonian Region (CPR) hosted some of the largest silicic volcanic eruptions in Europe during the Early and Middle Miocene contemporaneously with the major lithospheric thinning of the rift Pannonian Basin, which was recorded as an ignimbrite flare-up event from ~18.1 Ma to ~14.4 Ma. In order to gain in-depth perspectives on the eruption chronology, tephrostratigraphy, and petrogenesis at the onset of CPR silicic volcanism, we applied a multi-proxy approach on the Lower Miocene rhyolitic ignimbrites and volcaniclastic deposits ranging from the northern CPR to the Dinaride Lake System. High-precision zircon geochronology indicates there were two discrete pulses of volcanic activity at ~18.1 Ma and ~17.3 Ma. Based on combined tephrostratigraphic signatures, we propose that large 18.1 Ma Kalnik and 17.3 Ma Eger eruption events produced far- traveled, massive rhyolitic ignimbrites, which were deposited across northern and southwestern regions of the CPR. Due to easterly winds which carried volcanic ash hundreds of kilometers to the southwest, Eger eruption products also reached distal intra- montane Dinaridic lacustrine basins. Both events therefore capture important marker horizons in basin stratigraphy. Integrated zircon and bulk glass Nd-Hf isotope compositions have a positive correlation, defining a regional mantle array. A systematic isotopic change was recorded, moving from more crustal signatures in older eruptive events towards more juvenile compositions through time. This implies variations in the interaction between metasomatized lithospheric mantle-derived magmas and various crustal melts with time. It is likely that CPR eruptions also contributed significant protolith material for subsequent Dinaridic karst bauxites in the region. By combining our new volcanic data set with high- precision zircon petrochronology from these bauxites, it is possible to refine models of transport of weathered material and provide a glimpse into CPR magmatic evolution during Early Miocene lithospheric thinning. Finally, these geochronology data from the bauxites help constrain broader Miocene environmental processes by constraining the timing of bauxitization in paleo mid-latitude Europe, providing continental paleoclimate data, and provide significant insight into the Miocene Climatic Optimum.

The survey area includes the Dinarides and the peripheral areas of the Pannonian Basin and the Adriatic Sea, and it’s located at the collision of the Adriatic microplate and the Pannonian tectonic segment of Eurasia. The basic goal of the research is to determine a three-dimensional geological model of the crust and the uppermost mantle based on three-dimensional gravity and seismic models. The density model was determined based on 2D- gravity modelling according to the methodology applied by Šumanovac (2010). Gravity modelling is characterized by relatively wide ambiguity limits, but using the so-called "calibrated density set", they can be significantly constricted. The modelling was performed on the Alp07 profile and five gravity profiles placed approximately perpendicular to the Dinarides extension. The basic assumption is that the structure of the Dinarides is generally two-dimensional. This would mean that the geological properties along the Dinarides do not change, so the calibration of the density set is made on the Alp07 profile in the northern Dinarides. The two-dimensionality of the geological structure is clearly evident on regional geological and gravity maps, especially the Bouguer anomaly map. Based on two-dimensional density models of gravity profiles, a three- dimensional density model was developed, which clearly presents the relationships in the survey area. Two velocity models were constructed. The first model was constructed by converting the density model into velocities. The procedure opposite to the determination of the calibrated density set is now used. However, this transfer is now made on a 3D-density model, so a 3D-velocity model has been constructed to be able to correlate with the velocity model obtained by seismic method. The second velocity model of the Dinarides and marginal areas was determined by local earthquake tomography by means of inverse seismic modelling. By correlating all geophysical models, the first three-dimensional geological model in the area of the Dinarides and marginal areas was determined. The smallest thicknesses of the crust, only about 20 km, are located below the Pannonian Basin, and the crust is apparently single-layered. Small crust thicknesses, 25-30 km, are also found in the Adriatic Sea, the area of the undeformed Adriatic microplate. Beneath the Dinarides the crust thickens abruptly, and the greatest thicknesses lie below the centre of the Dinarides in a narrow and regular zone with a Dinaridic extension. The width of the Moho depression along the Dinarides is largely similar, but the maximum depths of the Moho changing from 45 km in the northern to 50 km in the southern Dinarides. Between the two-layer Dinaridic crust, which includes the Adriatic units, and the single-layer Pannonian crust, which includes European units, there is a wide Transitional Zone. It plays the role of a suture zone of two continents, Africa and Europe. The most prominent phenomenon is the high density body below the Sava Depression, which can be interpreted as a larger block of oceanic crust rocks.

The study area represents the contact between the Adriatic microplate as part of the African plate and the Pannonian basin as part of the Eurasian plate. This investigation is a continuation of the geophysical studies focused on the Dinarides and its adjacent areas. So far, several structural models based on 3D geophysical models of the upper mantle have been proposed, while there was no complete high-resolution geophysical model of the crust and the transition zone to the upper mantle. Our goal was to provide the first high-resolution 3D velocity model of the crust and the uppermost mantle in the broader Dinarides region. We applied the method of Local Earthquake Tomography (LET). The data sets of P-wave propagation times, calculated from earthquakes recorded by temporary and permanent seismic stations in the study area, were inverted to obtain a three-dimensional P-wave velocity model. The new geophysical model provided the best resolution of the uppermost mantle yet achieved in this study area and in a model of this scale. We assumed that the model would better reveal the structures of the crust. However, our model revealed features at the level of the lowermost crust and upper mantle that had previously been considered only on the basis of geologic relationships at the surface or structures within the crust projected to the level of the mantle. To date, there's no structural model of the crust- mantle transition based on 3D geophysical data that directly samples the lower crust and upper mantle. The resolution documented by the resolution tests is less than a hundred kilometers in the horizontal direction and a few kilometers in the vertical direction in the area with good ray coverage. The most reliable feature of the model concerns the structure of the lower crust and uppermost mantle. The model confirms previous findings of crustal thickening beneath the Dinarides and crustal thinning beneath the Pannonian Basin. The Moho shape is based on the highest vertical velocity gradient in the lower crust, and the depth of the boundary corresponds to the velocity surface of about 7 km/s. Under the Dinarides, there is a deep low velocity zone that extends to depths greater than 55 km and has a characteristic NW–SE trend. The pronounced low velocity anomaly (Vp less than 7.5 km/s) is surrounded by higher velocities typical of the uppermost mantle. The deep, low velocity anomaly occurring in the uppermost mantle and traced along the Dinarides can be explained by two models: a broad shear zone at the contact between two mantles or a subsided part of the lower Adriatic crust beneath the Pannonian lithospheric mantle. Therefore, we performed two- dimensional forward gravimetric modeling to reduce the ambiguity of interpretation. The anomaly is interpreted as fragmentation in the uppermost mantle. The high and low velocity alteration in the narrow region below the Dinarides may be the first geophysical evidence of contact between the Adriatic and Pannonian mantles. According to the velocity pattern, the contact zone can be located at the NE flank of the Dinarides.

The Dinaridic metallogenic province is a part of the Alpine–Himalayan orogenic system, developed as a result of opening and closure of the Neo-Tethys Ocean by convergence of the African and Eurasian plates. The northern boundary of the Dinarides is related to the northern African margin (Adria–Apulia). The Tisia mega-unit, a small continental block, positioned between the Dinarides and the Carpathians, is genetically related to the South Eurasian margin. The geology of the Dinarides is constrained by the Alpine Wilson cycle. The major stages of the cycle are: (a) Permian early intra-continental rifting ; (b) Triassic advanced rifting ; (c) Jurassic oceanization ; (d) Cretaceous subduction ; (e) Paleogene collision ; and (f) Neogene post-collision and extension followed by orogenic collapse. Each stage creates characteristic ore deposits related to the specific geological environments. Stage (a) bears hydrothermal siderite-barite-polysulphide deposits, epigenetic sedimentary uranium deposits, red bed-type, sabkha- type copper and barite deposits and evaporites. Stage (b) favored SEDEX and hydrothermal iron-polysulphide-barite-mercury and MVT deposits. Stage (c) developed chromites, asbestos, talc and magnesite deposits. The spatial position of stage (d) remains poorly constrained. The Southern Tisia unit might be a possible candidate for the Neo-Tethyan active continental margin with the Cretaceous subduction zone positioned beneath. Absence of voluminous subduction-related magmatism and mineral deposits, however, favors subduction within the Vardar zone (the easternmost Dinarides), adjoined to the Serbo-Macedonian ensialic terrain with its large porphyry-Cu deposits. Stage (e) was a prelude to the prolific phase (f) with its numerous hydrothermal Pb, Zn and Sb deposits that mostly occur in the western Vardar Zone. The presentation deals with metallogenic characteristics of the Dinarides, based on recently-gained knowledge on the regional geology, petrology and genesis of mineral deposits. Establishment of the plate tectonic model several decades ago greatly contributed to an integrated interpretation of ore deposit genesis. In turn, basic research in the field of ore genesis generated new data that can be used to improve the plate tectonic model.

The bauxite-bearing area Jajce is located northwest of the town of Jajce in the central part of Bosnia and Herzegovina. The region was exploited for karst bauxite during nearly a half a century activity. Geology of the area and the bauxite genesis were discussed in a number of papers. Geophysical surveys were also applied. Particularly important bauxite districts include Crvene Stijene, Bešpelj, Poljane and Liskovica. Our research was focused in the Bešpelj district, mined in open-pits and undergrounded mining, and giving opportunities for a detailed sampling and rock observations. Geochemical and mineralogical research of bauxites were made on the core samples of three boreholes. In total, 13 bauxite samples were studied by wet chemistry, ICP-MS (trace elements and REE), XRD, micro-XRF, optical microscopy, and differential thermic analysis. The bauxite deposits originated during the terrestrial phase in the stratigraphic range from the upper Albian to the Coniacian–Maastrichtian. The Jajce area is a part of the northeastern margin of the Adriatic Carbonate Platform, which existed from the end of the Early Jurassic up to the end of the Cretaceous. At the end of the Early Cretaceous and the beginning of the Late Cretaceous, the carbonate platform, as a passive continental margin, underwent an intensive compressional tectonics and emersion as a result of platform bulging. Hot humid climate and subaerial conditions were beneficial for effective bauxitization. The emersion lasted from late Albian to the Coniacian–Maastrichtian, approximately for 20 Ma. Six types of bauxites are distinguished: lenticular, canyon-like, graben type, sinkhole type, canyon-like with a sinkhole at the bottom and tectonized ones (Pavičić et al., 2018). The bauxite deposits are mainly composed of carbonate clastics and limestones of Late Cretaceous age, exceeding thickness of 1000 m. The boundary between the Upper Cretaceous and the Paleogene clastics is not accurately defined. Bauxite lithology and genesis is defined by paleo- relief type and position of the water table and erosion basis. Deeply dissected karst, filled by а bauxitic material with synchronous bauxitization prefers vadose facies. The genetical observation recognizes juvenile, mature and senile phases. The complete profile is topped by an iron crust (duricrust). Bauxite lithogenesis is defined by pelitomorphic facies (mudstones with colloform texture, formed in a water saturated zone). Ooid/pisoid facies in the middle of the ore body assumes a development from autochtonous to allochtonous setting. Paleosoils attested with pedogenic formations, rhizopods and syneresis, point to a new transgression in the Late Cretaceous as a response to collisional tectonics. Flexural bulges, due to uplift of crustal segments, are typical of the orogenic foredeeps, in areas affected by an active thrusting, nappe stacking and tectonic loading. New beneficial subaerial bauxitization areas were formed and shifted toward the inner part of the Apulian carbonate platform (Adriatic-Dinaric), in post- Cretaceous times.