sedimentation settings

Terrigenous-mineralogic characteristics of the Bobrikovskian horizon within the Saratov Trans-Volga Region is provided in terms of the Berezovskaya group of rises. The quantitative and the qualitative composition changes of the heavy fraction minerals within the section have been determined. The lack of abrupt, intermittent changes of any material composition characteristics testifies to the section relative continuity.

Indicators of sedimentogenesis have been established for paleogeographic reconstructions based on ecosystem-nanostructural analysis of finely dispersed sediments. The Early Triassic Olenekian sediments have disclosed some features of primary food chains peculiar for marine basins within the landscapes previously regarded as continental ones. Those have been classified as plains periodically flooded by sea. The coccolith- and ostracod-bearing sediments from epicontinental basins have been recorded in the Middle Triassic sections.