Rhizolites and Signs of Pedogenesis from Upper Permian of Central Russia

Abstract

The remains of fossil roots (rhizolithes) of two morphotypes (M1 and M2) from Upper Permian deposits near the town of Vyazniki in the east of the Vladimir region are described. In the section, M1 rhizolites are vertically oriented and are represented by several types of preservation: rhizocretions, imprints of the roots surface and root petrifactions. The study of transverse and longitudinal sections of ferruginized root fragments showed that among the rhizolites there are three types of structure of the central conducting beam (stele). On two rhizolites, it was noticed that the places of branch of the lateral roots are located by four rhizostiches, which indicates a tetrarch type of stele for these roots. The discovery of the remains of root systems in an upright position and without any traces of transportation indicate the first stages of primary soil formation. M2 rhizolites are a network of finely intertwined roots. New findings of in situ rhizoliths are significantly complement our understanding the Late Permian paleoenvironments and paleoecosystems in the center of the Russian Platform.