Russian geologist, Professor at the St. Petersburg University, Corresponding Member of the St. Petersburg Academy of Sciences (since 1901). One of the founders and Chairman (since 1888) of the Society of Devotees of Natural Science, Anthropology, and Ethnography. Creator and curator of the Geological Museum at the University at the Department of Historical Geology (1868). Member of a number of geological, mineralogical, anthropological and other societies in Russia and abroad. Active State Councillor.
His scientific research was devoted to petrography, mineralogy, stratigraphy, palaeontology, and hydrogeology of the north of the European part of Russia. First applied (in 1867) the microscopic method in the study of rocks. Author of the textbook “Geology. General course”, repeatedly reprinted. He conducted field geological studies in Donbass, Crimea, the Caucasus, the Urals, Altai and other regions. He took part in the Commission for Water Supply and Sewerage of St. Petersburg, Moscow and other cities. He investigated the geological structure of St. Petersburg and the Neva River Valley. His name is given to the bay on the western coast of the Severny Island of Novaya Zemlya and numerous fossil forms from the classes of reptiles, brachiopods, bivalves, and cephalopods.