Abstract:
The plate tectonics theory has laid the foundation for a realistic model of tectogenesis and of geodynamics in general. But we now know that this model explains more-or-less satisfactorily only the kinematics of that part of the upper crust that lies within the major plates. The concept of a concentrically zonal, or shell, structure of the Earth has long been firmly rooted in the earth sciences. Only now we are beginning to recognize that each shell constitutes an autonomous dynamic system. The principle of universal mobility governs the relationships of the Earth's various shells and forms the basis of all geodynamics. It shows in an especially pronounced way in the interaction of the lithosphere, hydrosphere and atmosphere, but it is also valid for and applicable to the deeper-lying shells of the Earth. There is reason to believe that the interaction of the earth's shells intensifies during the epochs of most rapid liberation of the Earth's internal heat and becomes less intense in the intervening epochs. The alternation of such epochs is also reflected in fluctuations of the Earth's volume.