GEOCHRONOLOGICAL SCALES AND THE ASTRONOMIC TIME (STATE OF THE ART)

Abstract

A problem of modifying the International stratigraphic scale is discussed, and the present state of the Phanerozoic geochronological scale is analyzed. It is suggested that both scales reflect a combined response of the Earth subsystems (tectonosphere, biosphere, hydrosphere, and others) to powerful cosmic impacts on our planet, an element of the Solar System. The proposed ideas are supported by a theoretical model allowing to relate epochs of mass extinction of living organisms to periods of bombarding the Solar System by galactic comets and to moments of big asteroid impacts on the Earth. The proposed geological time scale that is calibrated with proper allowance for distribution of gravitational potential in the Galaxy is comparable in accuracy with the Phanerozoic geochronological scale.