Permian biospheric events in Northeast Asia

Abstract

An analysis of the dynamics of diversity of bivalve species in Northeast Asia in the Permian period allowed us to reveal a number of events when it significantly increased or decreased. Four major mass extinction events were established for bivalves: at the end of the Early Permian, in the Early Capitanian age, at the the Capitanian-Wuchiapingian boundary and at the end of the Late Permian. Along with extinction events, five events of taxonomic radiation/innovation were distinguished: Early Asselian, Middle Kungurian, Early Roadian, Late Wordian, and Early Changhsingian. Revealing of these biotic events has been confirmed by the dynamics of biodiversity in other major groups of Permian fauna (foraminifers, brachiopods, ammonoids). Moreover, they are evidenced in different basins by changes in the character of sedimentation, isotope parameters, eustatic variations and other environmental factors. Most of the events can be traced far beyond Northeast Asia. Their manifestation is associated with general reasons (variations in endogenous regime of the Earth and associated stress effects on the biota). According to this, results of studying these events can be used for global correlations.