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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.

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.

The Dinarides are an integral part of the Alpine orogenic belt and stretch over large parts of Slovenia, Croatia, Bosnia-Herzegovina, Monte Negro and Serbia. A great number of intra-montane basins formed in the interior of this Late Eocene to EarlyOligocene orogen during the Miocene. These basins harbored a suite of long-lived lakes, collectively called the Dinaride Lake System (DLS). Lake Livno, with its 600km2 of preserved surface, was the second largest of these Dinaride Lakes. At present, its deposits are divided between the Livno and Tomislavgrad basins, which were part of a single basin when Lake Livno first formed. High resolution age constraints for the over 2km basin infill have been lacking up to now, partly due to the endemic nature of its lacustrine fauna. This severely hampered geodynamic as well as paleoenvironmental reconstructions. Here, we present a chronostratigraphy based on radioisotopic and magnetostratigraphic data. 40Ar/39Ar measurements reveal that the Tušnica volcanic ash, found in between the Gomphoteriumbearing coal seams at the base of the basin infill, is 17.00±0.17 Ma old. 40Ar/39Ar dating of the Mandek ash, correlative to the uppermost sedimentary unit, provides an age of 14.68±0.16 Ma. Correlation of the composite magnetostratigraphy for the main lacustrine depositional phase to the Astronomically Tuned Neogene Time Scale is straightforward and reveals that the majority of the deposits of Lake Livno accumulated between 17 Ma and approximately 13 Ma. The disappearance of Lake Livno is most likely attributable to a change in tectonic regime. Calcarenites and breccias, derived from the basin margins, first entered the lake around 14.8 Ma and subsequently coarsened and thickened upwards. The basinmargins were apparently gradually uplifted before subsidence stalled. Comparison with chronostratigraphic data for other constituents of the DLS leads to the conclusion that their lifetimes largely coincide. Finally, we calibrate the most important marker fossils of the various Dinaride basins to the geological time scale and we present a new biochronological scheme for the DLS.