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Investigations of the Upper Permian strata in the Iran-Transcaucasia resulted in identification of 32 ammonoid genera. The majority of ammonoids in this collection belong to the order Ceratitida (75%). Among Dzhulfian ceratitid ammonoids representatives of the family Araxoceratidae (Otoceratoidea) are most abundant. The assemblage structure changed radically during latest Permian (Dorashamian) time, bringing a domination of the family Dzhulfitidae. The Induan (Lower Triassic) succession in the Verkhoyansk area provided a few groups of ammonoids which are Palaeozoic in type: families Episageceratidae (Episageceras), Xenodiscidae (Aldanoceras and Metophiceras), and Dzhulfitidae (Tompophiceras) and superfamily Otoceratoidea (Otoceras and Vavilovites). It demonstrates the survival of ammonoids belonging to these groups the Permian--Triassic (P-T) boundary extinction event and their quick migration to the vast areas of higher latitudes (together with some representatives of theMesozoic-type families). Induan-Olenekian ammonoid successions in South Primorye, Mangyshlak, and Arctic Siberia illustrate the high rate of Early Triassic ammonoid recovery in both the Tethys and the Boreal realm. New ammonoid taxa are described: Proptychitina subordo nov., Ussuritina subordo nov., Subbalhaeceras shigetai gen. and sp. nov. (Flemingitidae), Mesohedenstroemia olgae sp. nov. (Hedenstrormiidae), and Inyoites sedini sp. nov. (Inyoitidae). [ABSTRACT FROM AUTHOR]

Palaeozoological, palaeobotanical and geochemical analyses of Lower Permian to the lowermost Cretaceous sediments exposed in the southern Russian Far East (Bureya-Jiamusi-Khanka superterrane and the Sergeevka terrane), and higher latitude areas (northern Russian Far East and Spitsbergen) suggest a direct relationship with global climatic events defined by the data from oxygen-isotopic palaeotemperatures. Several positive carbon-isotopic anomalies discovered within the uppermost Cisuralian, Guadalupian, early Lopingian and Aalenian-Bajocian intervals are possibly connected to strong hydrological intermixing of oceanic waters under the influence of considerable thermal gradients. [ABSTRACT FROM AUTHOR]

Palaeontological characteristics of the Upper Permian and upper Olenekian to lowermost Anisian sequences in the Tethys and the Boreal realm are reviewed in the context of global correlation. Data from key Wuchiapingian and Changhsingian sections in Transcaucasia, Lower and Middle Triassic sections in the Verkhoyansk area, Arctic Siberia, the southern Far East (South Primorye and Kitakami) and Mangyshlak (Kazakhstan) are examined. Dominant groups of ammonoids are shown for these different regions. Through correlation, it is suggested that significant thermal maxima (recognized using geochemical, palaeozoogeographical and palaeoecological data) existed during the late Kungurian, early Wuchiapingian, latest Changhsingian, middle Olenekian and earliest Anisian periods. Successive expansions and reductions of the warm–temperate climatic zones into middle and high latitudes during the Late Permian and the Early and Middle Triassic are a result of strong climatic fluctuations. [ABSTRACT FROM AUTHOR]