Tectonostratigraphic evolution of the Cretaceous–Paleogene Dinaric foreland basin in eastern Herzegovina

The Bosnian Flysch, deposited within the Dinaric foreland basin in eastern Herzegovina, consists of thick deep-sea turbiditic successions represented by the Lower Cretaceous Vranduk Formation and the Upper Cretaceous– Paleogene Ugar Formation. The Vranduk Formation in eastern Herzegovina is predominantly siliciclastic in nature, sourced from the northeasterly positioned Adria-derived continental basement units and Neotethys ophiolites. Biostratigraphic data suggest a Barremian to Albian age for the Vranduk Formation in this area. The Ugar Formation in eastern Herzegovina consists of three members: (i) basal Upper Cretaceous limestone breccias and conglomerates; (ii) Upper Cretaceous carbonate–clastic sediments; and (iii) Paleocene carbonate–siliciclastic sediments, derived from the SW situated Adriatic Carbonate Platform, and redeposited into the foreland basin. Our biostratigraphic data indicate a Turonian to Lower Santonian age for the basal breccias and conglomerates, an Upper Santonian to Maastrichtian age for the Upper Cretaceous carbonates, and a Paleocene age for the carbonate–clastic sediments. Kinematic analysis of faults and the reconstruction of paleostress fields have identified three significant and temporally distinct tectonic phases. ... mehrReverse and strike-slip faults were active during the Cretaceous–Paleogene deformation phase, which developed under compression of a general NE–SW orientation. The second deformation is characterized by a regional event, the Oligocene–Miocene extension, during which older reverse structures were reactivated as normal faults, and new normal faults were also developed. Here, normal faults active in extension parallel to the orogen (NW–SE orientation) and those active in extension perpendicular to the orogen (NE–SW orientation) can be distinguished. The youngest, Late Miocene deformation phase is documented by a group of faults active in compression that affected the entire Dinarides. This stress field was characterized by reverse and strike-slip faults active in N–S oriented compression.