Home – Home – Jornals – Russian Geology and Geophysics 2015 number 4

The International Stratigraphic Chart of the Phanerozoic is constructed by drawing lower boundaries of stratigraphic units with reference to Global Boundary Stratotype Section and Point . Some systems retain former, usually European, names of stages, whereas new sequences of stages are proposed for others, such as Cambrian and Ordovician. The boundaries of 64 stages of 100 had been approved by the beginning of 2014. Fifty-three of these boundaries were drawn with regard to biostratigraphic criteria; one, ichnological; six, magnetostratigraphic; two, chemostratigraphic; one, impact; and one, climatic criteria. Their type sections are distributed over continents as follows: thirty-nine in Europe, twelve in Asia, nine in North America, and four in Africa. They are located in 19 countries: ten in China, nine in the United Kingdom, nine in Italy, seven in the United States, six in France, five in Spain, three in Czech, two in Morocco, two in Sweden, and one in each of several more countries. Although none is in Russia, candidates are proposed for stages of the Cambrian, Carboniferous, Permian, Triassic, and Jurassic Systems. Type sections for the Sakmarian and Artinskian have already been agreed. With the present work speed, it will take two or three decades to complete the scale construction. The General Stratigraphic Scale of Russia and the International Chart gradually converge. Their similarity at the stage level is 84%. Major disagreements exist only in the Cambrian and Permian Systems.