VOLUME 43 (1-3)/December 2014

The area of the town of Etropole is famous for the well-preserved Lower Bajocian ammonites, which can be still often found in the nearly located exposures. These ammonites were the source of a number of species that enabled the recognition of the Bajocian in Bulgaria. The ammonite faunas and their host rocks were allocated to a series of stratigraphic horizons that composed the stratotype section designated as the reference standard for the definition and characterization of the Etropole Formation. The latter includes an ammonite spectrum which is composed of both Lower Bajocian species of Northwest European distribution and proper Bulgarian dispersal. It contains rare examples of the ammonite families Graphoceratidae and Sphaeroceratidae, frequent ammonites of the family Sonniniidae, and much more common members of the families Oppeliidae, Otoitidae and Stephanoceratidae that define a biostratigraphic interval from the Hyperlioceras discites to the Stephanoceras humphriesianum zones. This paper deals with the Lower Bajocian ammonite specimens hosted in the collection of the Historical Museum in Etropole (Bulgaria). The best preserved and the most valuable examples of this collection are described and figured. Although not purposefully collected, these ammonites give an excellent impression of the relative abundances of what is common and typical for stratotype section of the Etropole Formation. The study of this collection has triggered the rocks of the Etropole Formation (including the type-section) to be biostratigraphically reassessed, but this will be done elsewhere. Considering that both exposures and the fossil-bearing levels previously known from the Etropole area have now nearly disappeared, the ammonite collection of the Historical Museum in Etropole provides authentic specimens to be viewed. Besides, the collection forms an integral part of the overall heritage of the Etropole region and therefore offers both scientific and educational values.

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Sedimentological and mineralogical composition of Upper Cretaceous terrigenous and volcaniclastic sandstones are presented for the Coşuştea Nappe of the South Carpathians, Romania, in order to constrain the provenance and tectonic setting of deposition. Existing geochemical data on volcaniclastic rocks were interpreted using discrimination diagrams in order to get additional information. The Coşuştea Nappe includes terrigenous turbidites, overlain by upward coarsening sequences of volcaniclastic turbidites, both associated with a strongly dismembered mélange complex. Facies association and vertical facies distribution suggest that terrigenous successions are midfan turbidites, dominated by deposition in suprafan channels. Their sandstone mineralogy indicates that a major sediment source, located on the upper plate, provided detritus of Getic type metamorphic basement and withinplate volcanic rocks, with minor input from the accretionary wedge. Volcaniclastic sedimentation took place as dominantly sandstone deposition in supracone lobes, followed by coarse sedimentation as channelized debris flows. Vertical facies distribution suggests evolution in time from midfan to proximal fan turbidites. Mineralogical composition of volcaniclastic sandstones indicates provenance from a major volcanic source, with minor contributions from the accretionary wedge and from an upper continental plate supplying terrigenous siliciclastic detritus, and suggests that volcaniclastic turbidites accumulated in a trench or a slope forearc basin. Geochemical data indicate resedimented volcanic arc material, with intermediate to basic composition and calc-alkaline geochemistry. The volcanic source was very likely represented by the Maastrichtian volcanism related to the Banatitic Magmatic and Metallogenetic Belt from the western South Carpathians.