For approximately 120 years since the beginning of European geology up to Ihe present day. Croatian geoscience has included intensive geological research of the Dinaridc Ophiolite zone. Research results can be grouped into several periods depending on the basic predominant approaches of European and World geology. ( 1) During the flysch period, ophiolites were spatially connected with the flysch formations. (2) During the geosynclinal period ophiolites were classified into the Diabas-Hornstein Formation'. (3) During the transitional period, characterized by the elaboration or the Basic Geological Map, a voluminous data were collected which could not be incorporated in geosynclinal ideas. (4) The last period is charactcrized by modern geodynamic interpretations resulting from global tectonics.

The palynological data suggest a Late Silurian to ?Early Carboniferous sedimentation age for the weakly metamorphosed rocks from the Mts. Psunj, Papuk and Krndija (Slavonija, North Croatia). Palynofacies and organo-petrographic data indicate that the protolithic sedimentary rocks were deposited in comparatively calm, anoxic to suboxic depositional environments. The vitrinite reflectance data for the same samples indicate the coal rank of meta-anthracite or anchimetamorphic zone grading into the coal rank of meta-anthracite/semigraphite or anchimetamorphic/epimetamorphic zone.

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Petrological investigations and monazite dating are carried out on medium-grade metamorphic rocks (micaschist, gneiss and amphibolite) from the Kutjevačka Rijeka transect in the Slavonian Mts., Tisia Unit (NE Croatia). Field, mesoscopic and microstructural observations, as well as the preserved mineral chemistry, point to a single metamorphic event during peak assemblage growth reaching amphibolite facies conditions of ca. 600–650 °C and 8–11 kbar. Th, U and Pb contents of yttrium-rich accessory monazites indicate a pre-Variscan, i.e. Ordovician-Silurian age (444 ± 19 and 428 ± 25 Ma) for the medium-grade metamorphism of garnet-bearing micaschist.

Earlier paleomagnetic studies suggested that counterclockwise rotating Adriatic microplate could have triggered the youngest rotations in the Hrvatsko Zagorje area (in the Slavonian Mts) and in the Mura-Zala Depression. Since the named areas are located quite far from the Eastern Adriatic coast, we decided to study the Krsko and Karlovac Basins, which are situated in-between. From the collected 12 paleomagnetic localities (Badenian through Pontian sediments) ten yielded good paleomagnetic directions as a result of laboratory processing and statistical evaluation. They definitely point to the counterclockwise rotation of the area in post Early Pontian times. The angle of the rotation is about 20° (D=337°, I=50°, k=48, α 95=10°). Thus, we have found a missing tectonic link from the Hrvatsko Zagorje, Slavonian Mts and the Mura– Zala Basins to the Adriatic microplate and collected further paleomagnetic evidence for end of Miocene or even younger important tectonic movements in the South Pannonian Basin.

The Dinaridic Alpine ophiolites can be divided into two groups: 1) those of the Jurassic Dinaride Ophiolite Zone (DOZ) and 2) those of the Cretaceous-Early Paleogene (?) Sava-Vardar Zone (SVZ). However, geologically and petrologically they have so far been treated as a whole, and their geotectonic setting has not been reliably established. We have investigated ophiolite terranes from both regions in order to determine their tectonic setting. Our comparison is based on trace element data and characteristic elemental ratios correlated with ophiolite settings in recent oceans. We show that the DOZ tectonite peridotites are enriched in LREE and have high Ti/V ratios (up to 23), whereas the SVZ mantle rocks are LREE-depleted and have low Ti/V ratios (1-4). The DOZ cumulate gabbros and peridotites are characterized by increased Ni content and high Ba/Sr ratio, positive Eu anomalies and lower Cr# of spinels, comparable with MORB cumulates. The SVZ cumulates do not show a positive Eu anomaly and are characterized by higher concentrations of V, Zr and Y, and higher K/Nb, Ti/Zr, Zr/Sm ratios, which correlate with those from some recent back-arc settings. Essential differences between DOZ and SVZ basaltic rocks are as follows: high-Ti vs. low-Ti ophiolites: Ti/V = 20-50 vs. <20; higher Mg#, Ni, Cr, Nb and Ta vs. higher Rb and Ba; elemental ratios of Sr/Zr, Ti/Zr, Y/Nb, Zr/Nb, Th/Nb, Th/Ta, La/Nb, La/Ta and Sm/Hf are similar to those from recent back-arc settings. These geochemical data confirm the earlier geologic model of Pamić et al. (2002). These contrasting geochemical signatures are the result of different geochemical processes taking place in two different settings: a) MORB along an accretionary plate margin underlain by oceanic upper mantle, and b) BARB along a supra-subduction zone characterized by an obducting upper mantle wedge underlain by subducted oceanic crust, which was a source of fluids.

Permo-Triassic rift-related magmatism in the Dinarides produced an intrusive gabbro-diorite-syenite-granite formation and an extrusive basalt-andesite-dacite formation with abundant pyroclastic rocks. They are spatially and genetically related to Late Permian to Norian rift-related sedimentary formations of the Adriatic-Dinaridic carbonate platform (ADCP). The volcanic and pyroclastic rocks are interlayered with fossiliferous sediments that range between the Late Permian and Middle Norian; the plutonic rocks, which are intrusive into Late Paleozoic and Scythian-Anisian sediments, have radiometric ages ranging between 262 and 212 Ma. Based on major and trace element contents, rocks of the Permo-Triassic magmatic association originated by fractional crystallization from primitive alkalic basalt to olivine tholeiite melts. Volcanic rocks were affected by strong ocean-hydrothermal metamorphism. Initial 87Sr/86Sr ratio of 0.703 and d18O of 5.6‰ of the most primitive rocks indicate an upper mantle origin. Most ...

The Internal Dinarides include ten larger allochthonous pre-Alpine complexes, similar in many respects to those in the Eastern Alps, Carpathians and Rhodopes. The Dinaride Paleozoic complexes consist mainly of Devonian to Permian formations and are commonly associated with abundant Triassic sediments. In addition, the largest Paleozoic complexes contain subordinate Cambrian-Ordovician formations. The best developed Early Paleozoic complex, which occurs in western Macedonia, is composed of fossiliferous Cambrian metasediments with ophiolites and fossiliferous Ordovician metasediments, interlayered with subordinate metavolcanics and intruded by coeval Ordovician granitoids (461-465 Ma) that were overprinted during the Variscan and Alpine tectonogeneses. It is underthrust by Variscan formations and overthrust by Neoproterozoic Pelagonide formations. Parts of the Paleozoic Drina-Ivanjica complex are composed of fossiliferous Cambrian-Ordovician metasediments containing metamafics and metatuff that were overprinted by Early Cretaceous metamorphism. In the Mid-Bosnian Schist Mts, formations of presumed Cambrian- Ordovician age characteristically consist of gneiss and amphibolite, which can be compared to the Oetztal complexes of the Eastern Alps. Dinaridic Cambrian-Ordovician formations from all three areas were metamorphosed during the late Ordovician deformation under P-T conditions of greenschist and, to a lesser extent, epidote-amphibolite facies (400-500 °C and 4-5 Kbar). Based on geochemical data, Ordovician bimodal volcanics and granitoids indicate a geotectonic setting comparable to recent back-arc basins.

K–Ar and Ar–Ar whole rock and mineral ages are presented for 25 samples of metamorphic rocks from the Mid-Bosnian Schist Mts., representing one of the largest allochthonous Palaeozoic terranes incorporated within the Internal Dinarides. Four main age groups can be distinguished: 1) Variscan (∼343 Ma), 2) post-Variscan (288–238 Ma), 3) Early Cretaceous (mainly 121–92 Ma), and 4) Eocene (59–35 Ma) ages. Apart from this, an Oligocene (31 Ma) age was obtained on Alpine vein hyalophane. The radiometric dating indicates a polyphase metamorphic evolution of the Palaeozoic formations and suggests a pre-Carboniferous age of the volcano-sedimentary protoliths, an Early Carboniferous age of Variscan metamorphism and deformation, post-Variscan volcanism, an Early Cretaceous metamorphic overprint related to out-of-sequence thrusting of the Palaeozoic complex, and an Eocene and Oligocene metamorphic overprint related to the main Alpine compressional deformation and subsequent strike-slip faulting, and uplift of the metamorphic core. Accordingly, the Mid-Bosnian Schist Mts. can be correlated in its multistage geodynamic evolution with some Palaeozoic tectonostratigraphic units from the Austroalpine domain in the Eastern Alps.

Corundum-bearing amphibolites are part of the metamorphic basement of the Krivaja–Konjuh ultramafic massif in the Dinaride Ophiolite Zone in Bosnia. Pinkish corundum occurs as porphyroblasts and together with edenitic–pargasitic hornblende and anorthite within the amphibolites. Based on major and trace element contents, the protoliths of the corundum-bearing amphibolites were tholeiitic gabbro cumulates. Geothermobarometric estimations on the corundum-bearing amphibolites yielded preliminary P–T conditions of 620–830 °C and 6–10 kbar for amphibole and plagioclase inclusions inside corundum and 4.5–8 kbar for the main metamorphic assemblage. These estimates are thought to reflect the metamorphic conditions achieved during the Late Jurassic obduction of the Krivaja–Konjuh ultramafic massif onto ophiolite mélange. This study documents the mineralogy, petrology and geochemistry of these unusual corundum-bearing ophiolite-related edenite–pargasitic amphibolites.

Three Internal Dinaridic tectonostratigraphic units are included in the PANCARDI domain; 1) the Bosnian Flysch, composed of the Liassic to Berriasian Vranduk Subgroup and the Albian to Maastrichtian Ugar Subgroup, originating on the passive Tethyan margin, 2) the Dinaride Ophiolite Zone, made up of the Radiolarite Formation, ophiolite included within the Jurassic olistostrome mélange, and a Cretaceous overstep sequence, partly with Urgon-type(?) signatures, and 3) the Sava-Vardar Zone, composed of Cretaceous-Early Paleogene flysch, locally with subduction-related basalt-rhyolites, a Paleogene, very low to medium-grade metamorphic sequence originating from the Cretaceous-Paleogene flysch, Paleogene tectonized ophiolite mélange, Eocene syncollisional granitoid occurrences and Oligocene postcollisional ones, accompanied by coeval shoshonite and andesite. All these formations occur as allochthonous blocks within two segments of the southern and western Pannonian Basin. 1) In the adjoining Tisia-Dinarides segment, the Sava-Vardar Zone lithologies occur both at the surface and in the subsurface of the Pannonian Basin, as the result of postorogenic Dinarides-Tisia interaction. Those located in the basement were uplifted during the Oligocene wrench faulting, which controlled the initial development of the Sava and Drava depressions. Those found at the surface were emplaced during the Pliocene phase of strike-slip faulting. 2) More common are Internal Dinaridic fragments sandwiched within the Alps-Dinarides-Tisia (e.g. Carpathians) triple junction area, e.g. the Zagorje-Bükk-Meliata Zone. In its southwestern Sava Subzone occur fragments of the Bosnian Flysch Zone and Sava-Vardar Zone, represented by a Paleogene tectonized ophiolite mélange, Cretaceous-Paleogene flysch and postcollisional andesite-shoshonite. The northeastern Bükk-Meliata Subzone is composed of a Jurassic ophiolite mélange correlative to the Dinaride Ophiolite Zone, which in its Slovakian part is thrust by Triassic, mainly carbonate formations. The accompanying Mónosbél Flysch can be correlated with the Vranduk Subgroup of the Bosnian Flysch. The displacement of the Internal Dinaridic formations can only partly be explained by Tertiary escape (extrusion) tectonics.

The Dinaridic ophiolite related magnesites have averages of delta(13)C and delta(18)O of +1.3 vs. +26.1 parts per thousand for the Late Jurassic contactmetamorphic-type; -12.2 vs. +26.4 parts per thousand for the Oligocene vein magnesites; -8.8 vs. +27.7 parts per thousand for stockwork deposits; -1.1 vs. +31.5 parts per thousand for Miocene detrital magnesites; and +1.7 vs. +32.8 parts per thousand for Miocene Bela Stena sedimentary deposits. Authors compared carbon and oxygen isotope composition of ophiolite related Dinaridic and world known magnesites. Comparison pointed out the identical span of values for the vein and stockwork types and some differences, but still with the similar trend at sedimentary magnesite deposits.