Two benthic microbial assemblages from the Měnín-1 borehole (Early Cambrian, Czech Republic)

Abstract

Diverse, well preserved benthic microbial assemblages are described from two stratigraphic levels of the Mnn-1 borehole from southern Moravia. Abundant cyanobacterial sheets, acritarchs, prasinophytes, and acid-resistant tissues, together with the ichnological and petrological evidence, indicate a shallow marine environment with occasional terrestrial influence. A sheltered depositional environment enabled the preservation of algal coenobia and intracellular structures. A palynological assessment contributed to the more accurate biostratigraphy of the Early Cambrian sediments in southern Moravia and confirmed the large extent of the basal Cambrian deposits. Some microfossils suggest the possible presence of undisturbed marine sediments of Ediacaran age. The tectonic position of the Brunovistulicum in pre-Variscan Europe is discussed.