Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Volcanogenic interlayer (tonstein) in the Main coal seam of the Nýřany group of seams (Asturian) in the Plzeň region
Abstract
Professor Jurgen Schneider provided a sample of coal 40 x 20 x 20 cm in size from the collections of the Bergakademie Freiberg for our investigation. The sample contains a thin beige interlayer 1.5-2.5 mm thick, accompanied by a few tiny lenses of similar composition 1-2 mm long and reaching a maximum thickness of 0.2 mm. The sample obviously comes from Nýřany in the Plzeň (Pilsen) region, but the precise locality is not given. Petrographic examination shows that the sample consists of alternating bands of bituminous and sapropel coal and contains an assemblage of megaspores suggesting that it comes from the Main coal seam of the Nýřany group of seams (Seam I) that was extracted only from the abandoned Krimich (I) Mine. According to Purkyně (1913), the bands of sapropel coal in this mine occurred only in the western part of the coal field. The present study is the contribution to the knowledge of volcanic activity in the Nýřany Member of the Kladno Formation (Asturian to Cantabrian; Pešek and Tásler 1989).
