The Upper Triassic of northern Middle Siberia: stratigraphy and palynology

Abstract

The Lower Carnian succession in northern Middle Siberia includes continental and marine deposits. Bivalves, nautiloids and ammonites in the marine units provide biostratigraphic control for a palynological study of three important sections. Palynomorph associations from the base of the succession include forms that have previously been reported only from Norian and Rhaetian deposits in the Tethyan and Boreal realms. This suggests that, in comparison with other areas, the palynoflora of Siberia was more uniform throughout the Late Triassic, and that the Carnian and Norian stages have a miospore assemblage that is recognizable in a wide belt through Arctic Canada and northern Eurasia.

Implications of the Newark Supergroup-based astrochronology and geomagnetic polarity time scale (Newark-APTS) for the tempo and mode of the early diversification of the Dinosauria

“…Kü rschner et al (2007), Lucas & Tanner (2007) and Cirilli et al (2009) agreed with this hypothesis. Similarly, classic Rhaetian taxa of Europe, such as Rhaetipollis germanicus and Zebrasporites spp., extend into the Early Carnian near the Late Triassic North Pole in northern Middle Siberia (Kozur & Weems 2007;Ilyina & Egorov 2008). The idea that the vesicate monosulcate taxa Patinasporites, Enzonalasporites and Vallisporites might be geographically provincial is not completely unconventional.…”

“…There is a corresponding time-transgressive shift in facies in continental strata, reflected in vertical successions from red beds and evaporates to grey strata, sometimes with coals in the northern sections. Similarly, classic Rhaetian taxa of Europe, such as Rhaetipollis germanicus and Zebrasporites spp., extend into the Early Carnian near the Late Triassic North Pole in northern Middle Siberia (Kozur & Weems 2007;Ilyina & Egorov 2008). Thus, it is no surprise that the tropics contained floras that differed from the temperate region, or that a flora might be time-transgressive as central Pangea translated northward.…”

Triassic palynoevents in the circum-Arctic region

“…Among Russian publications, Yaroshenko et al (1991) reported on Lower Triassic palynology of the Pechora area. Works on the Upper Triassic include those of Fefilova (1986Fefilova ( , 1988Fefilova ( , 1990 and of Ilyina and Egorov (2008), who published on palynology from the Carnian of Siberia.…”

The temporal and spatial distribution of Triassic dinoflagellate cysts

“…Terrestrially derived material, mainly pollen and spores, dominate palynofloras from the Upper Triassic successions of the present Arctic (e.g. Suneby and Hills, 1988;Hochuli et al, 1989;Ilyina and Egorov, 2008;Vigran et al, 2014). However, marine palynomorphs are relatively common in parts of these successions (e.g.…”

“…Interestingly, despite the existence of ammonite-dated, fossiliferous marine successions from East Siberia (Russian Arctic) (Dagys et al, 1993, Egorov andMørk, 1998;Konstantinov et al, 2003;Ilyina and Egorov, 2008)…”