This study presents the results of the conodont biostratigraphy and microfacies analysis carried out on the pelagic limestones of the Upper Triassic Dovško Section in Slovenia, which represents the ...eastern part of the Slovenian Basin. The age of the section ranges from the Lacian 1 to the Alaunian 1. The Lacian part of the succession is predominantly characterized by the representatives of the genus
Ancyrogondolella
. Transitional morphologies towards Alaunian faunas first appear in the Lacian 3 and become common during the Lacian-Alaunian transition. This evolutionary development coincides with a shift in microfacies from a dominantly radiolarian-bearing mudstone-wackestone-packstone to a filament- dominated wackestone-packstone, and the formation of small neptunian dykes, which may reflect environmental perturbations and/or a change in basin geometry. The proliferation of the genera
Epigondolella
and
Mockina
is observed in the Alaunian part of the section, though the genus
Ancyrogondolella
is still present in this interval. Systematic description of the conodont taxa is provided, and seven new species and two new subspecies are established. The new advances will be of great value in further biostratigraphic studies, especially in areas without ammonoid faunas, and in the reconstruction of the paleogeography of the Slovenian Basin.
The study area is located in cental Slovenia, and geologically located at the junction between the Alps and the Dinarides. The Middle Triassic of this region is characterised by intense rifting ...manifested by differential subsidence and volcanism. This led to a major paleogeographic reorganisation of the region, where three paleogeographic domains formed in the Upper Triassic: The Julian Carbonate Platform in the north, the intermediate Slovenian Basin, both parts of the Southern Alps, and the Dinaric (Adriatic, Friuli) Carbonate Platform in the south, which today is a part of the External Dinarides that host the area of investigation. Prior to the installation of the Dinaric Carbonate Platfrom, i.e. in the Ladinian, the entire area of the preset-day External Dinarides broke up into numerous tectonic blocks that were exposed to either erosion or continental, shallow-marine, and deep-marine sedimentation. In this study, we analyse at small scale a complex transitional area between a local carbonate platform and the Kobilji curek basin (depositional area dominated by deeper marine sediments), located in the Rute Plateau in central Slovenia south of Ljubljana. During enhanced subsidence, the basin was filled with volcanic material (tuffs and volcanogenic clays and subordinate extrusive material), while the adjacent platform aggraded. The slope was positioned above active paleofaults. During relative sea level lowstand, the platform prograded across the basin. The study area is divided into four major tectonic paleoblocks. The NW paleoblock experienced the most enhanced subsidence, and the platform prograded twice in this area and was submerged again by the rejuvenated subsidence and/or sea-level rise. The second and third paleoblocks subsided only during discrete major subsidence events, and the carbonates of the platform and slope were soon reinstated therein. In the fourth paleoblock to the east the platform persisted during the Ladinian. In the Carnian, the entire study area became emerged, and continental clastics were deposited. These were then replaced by a uniform shallow marine/intertidal Hauptdolomit (Dolomia Principale) formation at the onset of the Norian. This study provides the first detailed reconstruction of the sedimentary evolution of small-scale Ladinian basin and platforms system in the northern External Dinarides.
The Ladinian Pseudozilian formation in the central part of the Sava Folds, Slovenia, was deposited in a deeper marine basin situated among the carbonate platforms lining the western margin of the ...Neotethys. The formation consists of shale and sandstone, hemipelagic limestone, volcanics, and volcanoclastics. At Dole pri Litiji, tuffaceous sandstone contains metre-scale olistoliths dominated by microbialites, solenoporacean algae, sponges, microproblematica and, to a minor extent, corals. Six types of fossil reef associations were recognized based on different proportions of these components. The presence of
Ladinella porata
Ott, dasycladaceans, and solenoporacean algae suggests the olistoliths originate from within the photic zone, perhaps the platform margin or the upper slope. Similar or even identical associations can be found in other Anisian to early Carnian reefs, suggesting the perseverance of reef associations that established themselves during the Middle Triassic recovery. Rather than replacing the older associations, new associations were added through time. The Anisian–early Carnian reef associations thus probably remained present even after the Late Triassic rise of scleractinian corals to dominance.
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