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The main accent of the thesis is related to the structure and emplacement mechanisms of the Botev Vrah Thrust -structure of regional importance for the Late Alpine structure of the Balkanides. The principal study methods include field observation and detailed geological mapping, meso- and microstructural analysis of deformed magmatic, metamorphic and sedimentary rocks of both hanging wall and footwall, geochronological methods (fission-track method, Ar-Ar dating), etc. On the basis of structural characteristics, metamorphic alteration and geochronological data a new subdivision of the pre-Alpine basement is proposed. The Upper Cretaceous-Paleogene sediments are described in detail. Their characteristics give evidence for the existence of a small basin in front of the advancing Botev Vrah Thrust. The study is focused on the geometry, architecture and kinematic features of the Botev Vrah Thrust. Meso-and microstructural characteristics of tectonites and estimation of deformation related to thrust emplacement in both hanging wall and footwall are performed. First kinematic data from the thrust zone are reported that indicate top-to-the N shearing. The observed structural features and geochronological data give evidence that the Botev Vrah Thrust represents a brittle fault zone formed in shallow crustal levels, at temperatures 120-250C. On the basis of geochronological data and structural investigations a thermochronological reconstruction of the tectonic evolution of Central Stara Planina Mountain is proposed. A new geodymamic model including Early Alpine to Neotectonic stage is presented.
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