The Ordovician-Silurian boundary in the Prague Basin, Bohemia

Volume: 43Start Page: 95End Page: 10

Gladiolites geinitzianus Barrande, 1850 (currently Retiolites geinitzianus; Graptolithina): proposed designation of a neotype

Volume: 53Start Page: 267End Page: 26

Carbon isotope chemostratigraphy of the Llandovery in northern peri-Gondwana: new data from the Barrandian area, Czech Republic; pp. 220–226

The first complete δ13Corg record of the uppermost Hirnantian to lower Telychian strata of the Barrandian area (northern peri-Gondwana) is presented based on 168 new samples. The new data from the study area reveal that the evolution of the Llandoverian organic carbon isotope reservoir was similar to that on other palaeoplates, but it differs from the development of the coeval carbonate carbon isotope reservoir in the absence of two δ13C excursions (i.e. the early Aeronian positive excursion in the upper part of the Demirastrites triangulatus graptolite Biozone and a negative excursion occurring close to the boundary between the Cystograptus vesiculosus and Coronograptus cyphus graptolite biozones)

Trace element variations as a proxy for reconstruction of palaeoenvironmental changes during the Late Aeronian faunal and carbon isotope perturbations: new data from the peri-Gondwanan region

Trace element variations in the Upper Aeronian (Llandovery, Lower Silurian), deep-water, black shale succession of the Barrandian area (Perunica) were studied across an interval associated with a graptolite mass extinction and global, positive carbon isotope anomaly. The main aim of the paper is to test whether distinct changes in graptolite diversity during Late Aeronian were linked with changes in deep sea water oxygenation. Using multiple geochemical proxies we documented high-frequency changes in oxygenation of sea water from sediments of the convolutus to linnaei (guerichi) biozones. Detailed comparison of graptolite diversity with those high-frequency oxygenation changes suggests that the long-term and step-wise Late Aeronian graptolite crisis was not significantly influenced by changes in oxygen level and thus it probably resulted by another causes. The collapse of global carbon cycle during the Late Aeronian probably only temporarily increased extinction rate of the long-term graptolite crisis and considerably decreased evenness of the uppermost Aeronian graptolite communities. The Aeronian graptolite mass extinction was thus primarily driven by other biotic and/or abiotic cause

Monograptus crenulatus Currently Monoclimacis crenulata Graptolithina Proposed Attribution Of The Specific Name To Elles And Wood 1911 And Proposed Designation Of A Lectotype

Volume: 49Start Page: 46End Page: 4