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.
