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Abstract

In the interval of the Triassic–Jurassic boundary up to 80% of marine species became extinct. The main hypotheses on the causes of this mass extinction are reviewed. The extinction was triggered by a power� ful eruption of basalts in the Central Atlantic Magmatic Province. In addition, several impact craters have been found. Extraterrestrial factors resulted in two main sequences of events: terrestrial, leading to strong vol� canism, and extraterrestrial (impact events). They produced similar effects: emissions of harmful chemical compounds and aerosols. Consequences included the greenhouse effect, darkening of the atmosphere (which prevented photosynthesis), stagnation of the oceans, and anoxia. Biological productivity decreased; food chains collapsed. As a result, all vital processes were disturbed, and a large portion of the biota went extinct.
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... The Triassic-Jurassic transition (Tr-J, 201.36 ± 0.17 Ma, Wotzlaw et al., 2014) is marked by the end-Triassic mass extinction, one of the "Big Five" extinction events of the Phanerozoic (Benton, 1995;Raup & Sepkoski, 1982;Sepkoski, 1981). The biotic turnover, ecological crisis, and environmental background across the Tr-J transition have drawn significant attention over the last decades (Barash, 2015;Hesselbo et al., 2007). The impact of the end-Triassic mass extinction on marine organisms has been extensively documented (e.g., radiolarians, Hallam, 2002;foraminifera, Michalík et al., 2007;ammonites and brachiopods, Tomašových & Siblík, 2007;corals and calcisponges, Stanley Jr. et al., 2018; bivalves, Atkinson et al., 2019). ...
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