Petrographische und geochemische Charakterisierung der Karbonatbänke aus der Forschungsbohrung Klonk-1 (Suchomasty / Tschechische Republik)

The subject of this study is a detailed characterisation of the limestone beds from the Silurian/Devonian boundary interval at the stratotype profile Klonk (Suchomasty /Czech Republic). For the Klonk-1 borehole was drilled to about 57 m depth near the outcrop. Based on a detailed core description altogether 141 limestone beds were sampled and analyzed for petrographical and geochemical proxies. The predominantly micritic, pale grey timestones consist of the three major mineralogical components calcite ($\overline{x}$ = 82 %), quartz ($\overline{x}$ = 9 %) and muscovite/illite ($\overline{x}$ = 3 %). The remaining part of about 6 % is distributed among the subordinated minerals dolomite, albite, chlorite and pyrite. The limestone microfacies of the boreholeKlonk-1 are characterized by a fine lamination with scarce fossil content. The mainly uniform type of lamination, the rare appearence of benthic organisms, the small grainsize (< 63 $\mu$m) and also the absence of cross-bedding structures indicate a relativelydistal, hemipelagic, sedimentary environment beneath the storm wave base. The appearance of short bursts of biodetritic debris mainly in the middle and the upper part of the core interrupt the hemipelagic sedimentation. These mostly cm-thick bioclasticlayers with erosive bases consist of crinoidal fragments, shells of orthoconic nautiloids as well as fragments of bivalves- and/or brachiopod-shells. Therefore everything indicates that we are dealing with debris flows or slides, resedimented as regional limited events in a low slope area. [...