The subject of research was the massive limestone exposed in the quarry at Lesno Brdo. Samples for microfacies analysis were taken. From a section logged across four floors of a quarry in the total lenght of 15,5 m. Macroscopically the section was divided into three facies: Fine-grained micritic limestone, represents 59% of the section. Microbialite boundstone can be found as a few decimeters to a few meters large square blocks or rounded globular bodies. It is located in the first 1.7 m of the section and represents 15.5% of the total lenght of the section. In addition to microbialite (stromatolite), sponges and coral are also found in a smaller proportion. The third facies is terebellidal limestone, which occurs in the form of irregular lenses, especially in the lower and middle part of the section. It represents 13% of the section. The fourth facies, breccia, is exposed only in the lower part of the quarry and was not included in the logged part of the quarry. The facies types due to their heterogenous nature were further divided into several microfacies. I divided the limestone macroscopicaly assigne as micritic into: peloid bioclastic grainstone, bioclastic peloid wackestone, peloid wackestone, grainstone with fragmented bioclasts, peloids and intraclasts, pelet wackestone, washed bioclastic packstone and bioclastic and oncoid floatstone. Terebellid limestone is divided into a terebellidal floatstone and a terebellidal rudstone. Boundstone is too diverse to be further divided. On the basis of the previously defined fossils, massive limestone in the Lesno Brdo quarry is believed to be Carnian in age. The exposed part in the Lesno Brdo quarry is only a minor part of the carbonate platform. This section was probably deposited on the upper part of the slope or at the edge of the carbonate platform. Depending on the presence of rudstone and grainstone textures the water had moderate energy.
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