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The Dinaric–Hellenic mountain belt bends where two fault systems transect the orogen: (1) the dextral Shkoder-Peja Transfer Zone (SPTZ), active sometime between the Late Cretaceous and middle Eocene; (2) the Shkoder-Peja Normal Fault (SPNF), which accommodated NW–SE directed orogen-parallel extension. The SPTZ dextrally offsets the Dinaric–Hellenic nappes by ~ 75 km, a displacement attributed to reactivation of an Early Mesozoic rift transfer zone in the Adriatic margin during Paleogene subduction of the Pindos Ocean. This subduction involved an initial counter-clockwise rotation of the Hellenides with respect to the Dinarides around a pole at the NW end of the Budva–Krasta–Cukali–Pindos Basin. The SPNF overprints the SPTZ and is a composite structure comprising five fault segments: four of them (Cukali–Tropoja, Decani, Rožaje, Istog) were active under ductile-to-brittle conditions. They downthrow the West Vardar Ophiolite in the hanging wall. The Cukali–Tropoja and Decani segments exhume domes with anchizonal-to-greenschist-facies metamorphism in their footwalls. These structures formed during a first-phase of extension and clockwise rotation, whose Paleocene age is constrained by cross-cutting relationships. A second extensional phase was accommodated mainly by the fifth (Dukagjini) segment of the SPNF, a subsurface normal fault bordering syn-rift, mid-late Miocene clastic and lacustrine sediments in the Dukagjini Basin (DB) that are sealed by Plio-Pleistocene strata. This later phase involved subsidence of Neogene basins at the Dinaric–Hellenic junction coupled with accelerated clockwise oroclinal bending. The driving force for clockwise rotation is thought to be bending and rollback of the untorn part of the Adriatic slab beneath the Hellenides. [ABSTRACT FROM AUTHOR]

Syn-orogenic extension is often associated with erosional and tectonic denudation focused in the footwall of large normal faults. The Shkoder-Peja Normal Fault (SPNF) at the junction of the Dinarides and Hellenides in northern Albania and Kosovo trends NE-SW, at high angles to the mountain belt. The SW part of the footwall of this fault is a doubly-plunging, upright fold (Cukali Dome) whose axis trends parallel to the SPNF. To the east, the SPNF footwall comprises the High Karst (HK) and East Bosnian Durmitor (EBD) nappes. The Cukali Dome deforms the Paleogene Dinaric nappes, including the Krasta-Cukali Nappe with its Middle Triassic to Early Eocene sediments.Post-depositional peak temperatures of ~301 ± 6°C in the Cukali flysch (youngest sediments of the dome, 55-52 Ma – Ypresian) obtained from Raman analysis of carbonaceous material point to a burial depth of 10-20 km given a geothermal gradient of 15-30°C. Apatite fission-track (AFT) data from three samples of the Cukali flysch yield central ages between 29 ± 9 Ma and 21 ± 6 Ma. Another five from in total eight samples that were collected along two profiles close to the western (Cukali Dome) and the eastern (EBD) ends of the SPNF yield central AFT ages between 34 ± 14 Ma and 21 ± 6 Ma.Peak temperatures in the foot- and hangingwall of the SPNF exceeded the upper limit of the partial annealing zone (PAZ) for apatite (~110 °C), suggesting that the fission tracks in apatites must have been completely reset during burial and before exhumation. This precludes an inherited signal and therefore mixed AFT age populations. Our results indicate burial (involving Dinaric folding and thrusting) followed by exhumation and cooling of the Cukali flysch, and along-strike of the SPNF footwall, happened between Middle Eocene (post-Ypresian, age of the sediments) and Early Miocene (youngest central AFT ages). These AFT ages are ≥ 4-5 Ma older than Mid-Miocene syn-rift clastics in the western Kosovo basin in the hanging wall of the SPNF. West-East oriented profiles through the basin show increasing thickness of Mid-Miocene to Plio-Pleistocene sediments to at least ~1 km toward the SPNF in the west. Offset of the base of the West Vardar ophiolite nappe (WVO) in the footwall of the SPNF with respect to the top of the WVO at the western Kosovo Basin indicates a minimum vertical throw of 3 km at the eastern SPNF termination near Peja. However, similar AFT ages across the SPNF indicate contemporaneous pre-middle Miocene cooling of both blocks along the SPNF. This indicates that main displacement on this branch of the SPNF pre-dated thermal equilibration to below the PAZ of the AFT system. Taken together, the data is best explained by one or more normal faults active at two times: (1) faulting on the main SPNF which accommodated Cukali Doming and exhumation of the SPNF footwall no later than late Oligocene-Early Miocene time. (2) Mid-Miocene to Plio-Pleistocene normal faulting, possibly in the hanging wall of (1), that lead to deposition of syn-rift clastics in the Kosovo Basin. [ABSTRACT FROM AUTHOR]