Middle Triassic extensional tectonics led to the formation of various sedimentary basins in the area of today`s Southern Alps. The subject of investigation was the Zatrnik limestone in Bled area. In the Blejski vintgar gorge, several partial sedimentological sections were loged. Samples for conodont analysis and microfacies analysis were taken. Thin sections of standard sizes were prepared in order to supplement field observations with microfacies analysis. Thin sections were also used for determination of microproblematica and foraminifers. Thin-bedded limestone consists of three different kinds of lithologies. First lithology consists of masive limestone (wackestone, packstone, grainstone and rudstone) with beds up to 1 meter thick. Second lithology is represented by medium to thick bedded (from 10 cm to 1m thick) micritic limestones (pakstone, wackestone, rudstone) and the third group are calcarenites (packestone, wackestone) with beds thick from 7 cm to 1 m. Five microfacies types with subgroups were determined: bioclastic-intraclastic wackestone (MF1), intraclastic packstone (MF2), well sorted bioclastic-peloidal-intraclastic grainstone/packstone (MF3), intraclastic rudstone (MF4), dolomite (MF5). Peloids and intraclasts are the most common grains. Microproblematica is the dominating group of bioclasts. Foraminifers, echinoderms, red and green algae, calcimicrobes, brachiopods, bryozoa, sponges, bivalves and gastropods. Fish teeth and holoturias can rarely be found in samples for conodont analysis. Cordevolian to Julian age was determined on the basis of the following conodont species: Paragondolella foliata Budurov, Quadralella polygnatiformis (Budurov & Stefanov), Quadralella sp., Paragondolella sp., Gladigondolella malayensis Nogami and Gladigondolella tethydis (Huckriede). This age is in agreement with findings of foraminifera: Austrocolomia marschalli Oberhauser, Cucurbita infundibuliformis Jablonský, Endotriada tyrrhenica Vachard, Martini, Rettori & Zaninetti, Hydrania dulloi Senowbari-Daryan, Koskinobullina socialis Cherchi & Schroeder, Palaeolituonella meridionalis (Luperto), Pseudonodosaria cf. obconica (Reuss), Reophax rudis Kristan-Tollmann, »Trochammina« jaunensis Brönnimann & Page, ?Miliolipora cuvillieri Brönnimann & Zaninetti and Piallina bronnimanni Martini, Rettori, Urošević & Zannetti. The Zatrnik limestone deposited on the slope of the basin, adjacent to a carbonate platform (toe of the slope), which can be confirmed by the presence of debris flow, sinsediment flow, biota, sedimentary textures and explicit microfacies groups.
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