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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.

In this paper, we describe the stratigraphical and structural features of the tectonic units cropping out along the Zlatibor-Maljen geotraverse, located in western Serbia at the boundary with Bosnia-Herzegovina, and we present also a I :100,000 scale geological map. The study area corresponds to a SSW-NNE geotraverse, where the main oceanic and continental tectonic units of the Dinaric-Hellenic belt are well exposed. Along this geotraverse, the tectonic pile includes at the top the units derived from the European Plate, here represented only by the Ljig Unit, that was thrust over the oceanic units, cropping out in two distinct massifs, the Zlatibor and Maljen ones. In both massifs the oceanic units consist of a sub-ophiolite m lange overthrust by an ophiolite unit represented exclusively by mantle peridotites with the metamorphic sole at their base. In turn the oceanic units overthrust the Adria-derived units, here represented by the East Bosnian-Durmitor and Drina-Ivanjica Units, respectively located westward and eastward of the Zlatibor Massif. The geological data and the tectonic reconstruction suggest that the ophiolites of the two may have originated in the same composite oceanic basin that experienced oceanic opening, intra-oceanic subduction, development of supra-subduction oceanic basins and finally closure, in a time span ranging from Middle Triassic to Late Jurassic. The stratigraphical and structural dataset presented in this paper allows some insights about the geodynamic history of the northern area of the Dinaric-Hellenic belt, as well as a comparison with the reconstructions proposed for the southernmost area by other authors.