The succession of the Lower Flyschoid Formation in the western parts of the Slovenian Basin is a turbidite complex of late early Aptian to early middle Cenomanian age. The stratigraphic gap at the base of the formation is longest in the most proximal successions, where it spans a time interval from at least the middle Berriasian to the late Albian. The duration of the stratigraphic gap becomes shorter further towards the central parts of the Slovenian Basin. Limestone breccias and calcarenites were deposited by debris- and turbidity currents in form of submarine fans. The source of the carbonate resediments was the Adriatic carbonate platform. Its' sedimentary evolution during the Cretaceous was primarily influenced by eustatic sea level changes and tectonic activity. The turbidite complex of the western parts of the basin can be subdivided into three systems. Aptian turbidite system 1, the Albian pelagic system and the Albian–Cenomanian turbidite system 2. The Aptian successions of carbonate resediments were a consequence of high levels of carbonate production on the platform, followed by an eustatic sea-level fall. The successions of Albian marlstones and claystones represent a pelagic sediment characteristic of the Southern Alps. They coincide with the Aptian/Albian emersion of the carbonate platform and decreased supply of carbonates towards the basinal environments. The Albian–Cenomanian successions of resediments are clearly related to reestablished carbonate production and tectonically driven reorganisation of the carbonate platform margins. These changes led to collapses of the platform margins and triggered gravity flows towards the basin. Cretaceous successions comparable to those of the Slovenian Basin were also deposited in the Transition zone between the Internal and External Dinarides. The successions of the Gora Formation are clearly comparable with the Lower Flyschoid Formation. The horizons of Campanian volcanoclastic bentonitic clays are an indication of direct proximity to the Internal Dinarides and the oceanic units.
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