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NORTH-WESTERN AND CENTRAL DINARIDES The Dinarides are an orogenic belt stretching 700 km along the northeastern margin of the Apulia microplates (Dercourt et al. 1993). In the north this highly complex folded, thrusted, and imbricated belt merges with the Southern Alps and in the southeast with the Hellenides (Pamić & Balen, 2001). The main tectonostratigraphic units of the Central Dinarides display a regular zonal pattern from the Apulia plate to the Tisia block. The tectonostratigraphic units are products of the Tethyan opening and closure during successive phases of the Alpine Wilson cycle, and are as follows: 1. Adriatic-Dinaridic carbonate platform (ADCP) – External Dinarides ; 2. Carbonate-clastic formations of the passive continental margin (Bosnian flysch), 3. Dinaridic ophiolites, 4. Units of the active con-tinental margin, olistostrom mélange, Sava-Vardar zone. The Internal Dinarides comprise units 2, 3 and 4. The Di-narides, as a whole, were thrust onto the units of the South Tisia block during the Pliocene. The northwesternmost part of the Dinarides does not exhibit the same regular patterns as the Central Dinarides. The Di-narides deflects NE-SW, as the Zagorje-Mid-Transdanubian Zone (ZMTZ) between the Zagreb-Zemplin Line (ZZL) and the Periadriatic-Balatone Line (PBL), (Pamić & Tomljenović 1998), largely covered by the Sava nappe composed of Upper Palaeozoic and Triassic formations. ZMTZ, which is also named the Sava composite mega-unit, after Haas & Kovács (2001), bears elements of the External and Internal Dinarides and Southern Alps as well. It was squeezed be-tween ZZL and PBL and extruded eastward by Tertiary indentation of the Adria (Apulia) microplate during formation of the Alps. ALPINE GEODYNAMICS AND METALLOGENY OF THE NW AND CENTRAL DINARIDES The possible boundary between Variscan and post-Variscan metallogenic events could be arbitrarily accommodated at the unconformity defined by Lower Carboniferous, deformed metamorphic basement and Lower-Middle Carboniferous flysch-type deposits, followed by the Upper Carboniferous-Permian molasse-type sedimentary rocks. The two Wilson cycles, Variscan (Post-Variscan) and Alpine could be separated by the beginning of Middle-Upper Permian red bed-type clastic sedimentation. ALPINE WILSON CYCLE The generation of the main tectono-stratigraphic units of the Dinarides, with characteristic lithologies is the result of a long-lasting evolution of the Dinaridic part of the Tethys. The stages of the Wilson cycle are recognized by specific magmatic formations responsible for the formation of a wide spectrum of mineral deposits and occurrences. In the NW and Central Dinarides one can recognize the following tectono-magmatic phases: 1. Early intracontinental rifting (Mid-dle-Late Permian, thermal doming, incipient magmatism) 2. Advanced rifting (Middle Triassic, extensive submarine and subaerial volcanism and plutonism, basalts, spilites, keratophyres, gabbros, andesite-diorites, ) 3. Oceanization, generation of oceanic crust, (Jurassic-Early Cretaceous), 4. Subduction (Cretaceous-Paleogene, emplacement of ophio-lites in the accretionary wedge formations, ophiolitic mélange, basalt-rhyolites), 5. Collision (Paleogene granitoids), and 6. Post-collision (Oligocene-Neogene andesite-dacites, granodiorites). From a metallogenic point of view the most pro-ductive were phases 1, 2 and 6. |
