Andrushkevich Oleg Yurievich RussiaKazanKazan Federal University, 18 Kremlyovskaya St., Kazan 420008, Russiaзаведующий лабораторией пробоподготовки gemmaol@bk.ru Author's articles Ichthyofauna of the border sediments of the Severodvinsky and Vyatsky stages in the Late Permian localities in the west of the Orenburg region (Samara river basin) The investigation of the porosity scale effect and elastic anisotropy in Bashkirian limestones