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The Sarajevo-Zenica Basin of Bosnia-Herzegovina was part of the Dinaride Lake System, a large network of Miocene long-lived freshwater basins in southeastern Europe. The basin contains a thick sedimentary succession of carbonates, coals and mixed siliciclastic deposits that reflects the paleoclimatic and tectonic evolution of the region. In this study, we present novel integrated (magneto- bio)stratigraphic and sedimentological data and reconstruct the paleoenvironmental evolution of the Sarajevo-Zenica Basin during its two main evolutionary phases (thrusting and extension). The basal “Oligo-Miocene” freshwater paleoenvironments are characterized by alternating palustrine, shallow lacustrine and distal fluvial phases. The base level fluctuations are largely controlled by syn- sedimentary pulses of tectonic loading during the final phase of thrusting in the Internal Dinarides. The majority of this succession is considered early Miocene in age, which contrasts with previous Oligocene age estimates. The subsequent extensional phase initiated not later than ~18.4 Ma. This coarsening upward sequence of lacustrine carbonates, silts, sands and conglomerates is correlated between 17.2 and 15 Ma (C5Cr-C5Br) by means of integrated bio-magnetostratigraphy. During this upper extensional phase, subsidence and sediment influx was generally controlled by activity along the basin bounding normal fault, overruling smaller scale climatic influences. We conclude that the existence of the long- lived Sarajevo lake is coeval with other Dinaric and southern Pannonian lakes, and overlaps in time with the Miocene Climatic Optimum. Sedimentation in the Sarajevo-Zenica basin terminated at ~15–14 Ma which concurs with both the end of the climatic optimum as well as the cessation of extension in the Dinarides. These results will help to better quantify the paleoclimatic changes in the Dinaride Lake System as well as the regional tectono-sedimentary events, such as potential migrations of deformation across the Dinarides.

The coupled tectonic and depositional history of extensional basins is usually described in terms of stratigraphic sequences linked with the activity of normal faults. This depositional-kinematic interplay is less understood in basins bounded by major extensional detachments or normal fault systems associated with significant exhumation of footwalls. Of particular interest is the link between tectonics and sedimentation during the migration of normal faulting in time and space across the basin. One area where such coupled depositional-kinematic history can be optimally studied is the Late Oligocene - Miocene Sarajevo-Zenica Basin, located in the Dinarides Mountains of Bosnia and Herzegovina. This intra-montane basin recorded Oligocene – Pliocene sedimentation in an endemic and isolated lake environment. We use field kinematic and sedimentological mapping in outcrops correlated with existing local and regional studies to derive a high-resolution evolutionary model of the basin. The novel results demonstrate a close correlation between moments of normal faulting and high-order sedimentological cycles, while the overall extensional basin was filled by a largely uni-directional sediment supply from the neighbouring mountain chain. The migration in time and space of listric NE-dipping normal faults was associated with a gradual shift of the sedimentological environment. Transgressive-regressive cycles reflect sequential displacements on normal faults and their footwall exhumation, defining a new sedimentological model for such basins. This Early - Middle Miocene extension affected the central part of the Dinarides and was associated with the larger opening of the neighbouring Pannonian Basin. The extension was preceded and followed by two phases of contraction. The Oligocene - Early Miocene thrusting took place during the final stages of the Dinarides collision, while the post-Middle Miocene contraction is correlated with the regional indentation of the Adriatic continental unit. This latter phase inverted the extensional basin by reactivating the inherited basal listric detachment.

The Ljubija Fe carbonates-sulfide-barite ore field (44.55° N, 16.3° E) is located at the margin of Mesozoic carbonate platform, within Sana-Una river Paleozoic terrain, Inner Dinarides, 180 km NW from Sarajevo, Bosnia and Herzegovina. Fe carbonates occur as stratabound siderite and ankerite replacement in limestones and siderite-sulphide veins placed within shales. Mineralization is hosted by Middle Carboniferous sedimentary formation represented mainly by clastics (subgraywackes, graywackes, sandstones and organic-rich shales) and carbonate blocks placed within shales. Barite veins with fluorite are occurred within upper parts of ore deposit (Palinkaš, 1988). The main types of iron ore are (1) microcrystalline dark siderite and ankerite ; (2) sparry siderite veins within shales, contain sulfides and quartz ; (3) "zebra" siderite contains cavities infilled with sparry ankerite, quartz, sulfides and alteration phyllosilicates as tossudite and cookeite. Carbon and oxygen isotopic composition of mineralized and barren carbonates were determined in order to constrain the origin and nature of Fe-mineralization. The data have been obtained on the 54 carbonates from 32 hand samples. Based on textural and geochemical characteristics several generations of carbonates can be distinguished. The average d13C value of organic rich fine-grained limestone non-affected by mineralizing fluid of +1.6 +/- 0.4 ‰ V-PDB corresponds well to the world-wide Phanerozoic marine carbonates values. Affected limestones are slightly depleted on 13C. Light calcite veins which cut dark limestones affected by mineralizing fluid show δ 13C value of 0.2 +/- 0.16‰ . Microcrystalline dark ankerite with the average d13C and d18O values of -0.1 +/- 0.3 ‰ and +19.3 +/- 0.2 ‰ , respectively, has been identified to belong to the first Fe-carbonate generation. Microcrystalline dark siderite and dark siderite from zebra ore have the same average d13C. The next generation of Fe-carbonates is presented by light siderite from zebra ore with average d13C and d18O values of -2.3 +/- 0.8 ‰ and +19.7 +/- 0.6 ‰ , respectively. Ankerite sample isolated from zebra ore shows slightly depletion on 13C with average d13C value of -2.4 ‰ and d18O value of +15.9 ‰ . Sparry vein siderite is distinguished as the last generation of Fe-carbonates with average d13C and d18O values of -2.5 +/- 1.1 ‰ and +20.4 +/- 2.0 ‰ , respectively. Variations in d13C values of the host limestones and Fe carbonates point to progressive metasomatic replacement of calcite by siderite and can not be explain as a product of the synsedimentary event. The replacement of limestones by Fe-carbonates is a volume-for-volume process and result of two separate but coeval reactions - dissolution of the host mineral and precipitation of the replacing mineral (Garrels and Dreyer, 1952). Zebra ore was formed at the place where hot, acid fluid affected limestones. Volumetric rate of calcite dissolution was higher then volumetric rate of siderite precipitation. Dark fine grained (metasomatic) siderite was precipitated when fluid of lower temperature and acidity reacted with the host limestones. Volumetric rate of calcite dissolution was equal to volumetric rate of siderite precipitation i.e. primary texture was retained. Bicarbonate ions have been leached from limestones in reaction with mineralizing fluids. Fluids enriched on HCO3- deposited vein siderite within shales as the latter generation of Fe carbonates. Crystallization temperature of dark siderite was calculated from oxygen isotope fractionation between siderite and recrystallized calcite. Calcite-water and siderite-water equations by Zhang (1999) gave an apparent isotope equilibration temperature of 224°C. Fluid in isotopic equilibrium with both siderite and recrystallized calcite at the calculated temperature should have a d18O of 11.5‰ V-SMOW.