Carbon Isotope Stratigraphy
Middle Triassic carbon isotope stratigraphy revealed that isotopic perturbations in the Mecsek Mts., SW Hungary, record environmental variability that can be correlated with similar successions in the Germanic Basin and Dinaridic-Carpathian-Alpine region but not globally. Therefore, in SW Hungary, carbon isotope stratigraphy cannot be tied to the global carbon cycle and to the biotic recovery after the end-Permian mass extinction.
Outcrop of the Kozár Limestone in the Mecsek Mts., SW Hungary
Tracing Middle Triassic Volcanism
Enigmatic sideritic–kaolinitic and green clay layers of in the Mecsek Mts. (SW Hungary) have previously been interpreted as indicators of Tethyan volcanism in the otherwise germanotype Middle Triassic succession. Our investigations did not confirm a volcanogenic origin of these sediments. We suggest instead that the sideritic–kaolinitic layers formed in a freshwater swamp under humid, tropical climatic conditions during the Late Triassic to Early Jurassic and were tectonically placed over Middle Triassic carbonates. Whereas, the illitic green clay layers intercalated in the Middle Triassic dolostone may represent terrigenous deposits, and the illite mineralogy is the result of burial diagenesis of detrital clays.
Scanning Electron Image of illite and calcite from the green clay layers