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The Ozren ophiolite complex (OOC) of the Dinaridic Ophiolite Belt is one of the six ophiolite complexes in Bosnia and Herzegovina. This paper deals with the mineral chemistry of amphiboles determined by electron probe micro-analysis and micro-Raman spectroscopy. The detected amphibole generations and types in mafic, ultramafic, and metamorphic rocks suggest a polystage evolution and are therefore useful petrogenetic indicators of the investigated OOC. Most gabbroic rocks and dolerites contain primary magmatic amphibole1 (magnesio-hornblende to pargasite, occasionally hastingsite) and prismatic to needle-like aggregates of late magmatic amphibole2 (magnesio-hornblende), while plagiogranite contains ferri-winchite and ferro-ferri-winchite as primary magmatic amphibole. Post-magmatic amphiboles were detected in dolerites, troctolites, and lesser in peridotites. The Na-(Ti)-rich amphibole3 (ferri-winchite and ferro-ferri-winchite to katophorite and ferri-katophorite) with amphibole4 (grunerite) rim formed along the grain boundaries of clinopyroxene, amphibole1, and plagioclase in dolerites. A part of these amphiboles grows into amphibole1, 2. Kaersutite to ferri-kaersutite, associated with phlogopite, occur in troctolites and dunites, while Mhbl was detected in harzburgite. The ultramafic rocks (lherzolites, harzburgites, and dunites) and the gabbroic layer are crosscut by clinopyroxene–plagioclase gabbroic and clinopyroxene–plagioclase–amphibole gabbro–dolerite dykes, suggesting 'dry' and 'hydrated' percolating melts generated in inferred subridge and supra-subduction settings, respectively. The amphibole3 and 4 in gabbros and dolerites and similar amphibole types in ultramafic rocks could be related to inferred arc-type basaltic and plagiogranitic percolating melts and fluids. Low-Al amphibole5 (tremolite and actinolite) and associated chlorite, albite, and clinozoisite represent the ocean-floor alterations in mafic rocks. Amphibole6 (magnesio-hornblende to pargasite) was identified in metamorphic sole amphibolites. Micro-Raman spectroscopy provided typical Raman spectra for the studied amphiboles, highlighting distinct features such as bands related to CMg content, CFe3+ presence, TO4 ring-breathing mode, TiO6 stretching mode, presence > 0.3 apfu of CTi, and TO4 stretching indicating CFe2+ in the structure. Applied amphibole geothermobarometry revealed the formation P–T conditions of amphibole (Amp)1 (avg. 863 °C at 0.23 GPa), Amp2 (avg. 747 °C at 0.17 GPa), Amp in the mantle rocks (avg. 853 °C at 0.64 GPa), Amp5 (avg. 349 °C at 0.03 GPa), and Amp6 (avg. 694 °C at 0.46 GPa). [ABSTRACT FROM AUTHOR]

The Čaklovići geological cross-section is located in the Tuzla basin, about 7 km south-eastern from the Tuzla. The southern limb of Čaklovići anticline is made by sedimentary rocks. Based on paleontological research and principle of superposition, the sedimentary rocks of this area are divided on the Lower and the Middle Miocene. The Lower Miocene is dominantly composed by laminated and thinly stratified marlstones in which we can find layers of conglomerates and sandstones. Laminated marlstones contain pieces of mollusc shells. The basis of the Lower Miocene is made from tuff layer that is about 3 meters thick. These sediments were deposited in a coastal part of a freshtwater lake. Total thickness of the Lower Miocene sediments is about 33 meters. The Middle Miocene is defined based on foraminifera, which belong to zones of the Lower Badenian. The older part of the Lower Badenian is represented by Ammonia viennensis and Nonion commune zone. This zone is exclusively represented by marlstones with massive structure. Layered marlstone is only found in one centrimetric interval, in the upper part of this zone. Typical macrofossil associations for this part of the Lower Badenian are Aporrhais and Tellina. These molluscs in Tuzla basin are represented in immediate upper layer of rock salt deposits, in which we can find identical foraminifera zone. Massive marlstones of the older part of the Lower Badenian were deposited in infralittoral zone of the Central Paratethys, and their thickness is about 50 meters. The last part of researched Čaklovići cross-section is made by massive marlstones, sandstones and conglomerates. This sequence of geological cross-section is a part of the Lower Badenian, precisely it belongs to the zone Globigerinoides trilobus and Orbulina suturalis. Typical macrofossils of younger part of the Lower Badenian are Vaginella and Corbula. Sediments of this the Badenian section were deposited in circalittoral of the Central Paratethys. Their researched thickness is about 7 meters, and their total thickness is over 100 meters for sure. Based on previously researched cross-sections of the Lower Badenian in the Tuzla basin, it was concluded that same foraminifera zones are identical to nannoplankton zone NN5 (Martini, 1971). Čaklovići cross-section points out that in this part of the Tuzla basin, there were no salt formation deposits and in this part of the basin marine deposits are found unconformiticaly over freshwater lake sediments. These marine deposits are regularly representing immediate roof sediments of the salt formation. The studied cross-section is a exception in the Tuzla basin, and it's uniqe because of the fact that the margin between foraminifera zones is visible because of the erosion, hence it's available for different geological researches. [ABSTRACT FROM AUTHOR]