Viszlát triász, szia jura: Egy eseménydús időszakhatár rétegtana és földtörténeteud(Goodbye Triassic, hello Jurassic: Stratigraphy and Earth history across an eventful periodudboundary)

摘要

The boundary between the Triassic and Jurassic periods and systems has long been recognized to coincideudwith some of the most remarkable events in the Mesozoic. Here I briefly review the synchronousudmass extinction in marine and terrestrial ecosystems, global greenhouse warming, and major perturbationsudin the carbon cycle recorded in carbon isotope excursions, as signals of linked changes in theudEarth system. Extensive continental flood basalt volcanism ofthe Central Atlantic Magmatic Provinceudis likely to have triggered all these events, starting a cascade of environmental and biotic crises. Recentudstudies by our research team in stratigraphic sections in Hungary and Austria have also contributedudto the development of models ofTriassic-Jurassic boundary events. The Global Stratotype Sectionudand Point for the Triassic-Jurassic boundary has recently been defined in the Kuhjoch section (Tyrol,udAustria) at the first appearance of the ammonite Psiloceras spelae. This level slightly postdates theudmain changes in this and other correlative sections.