On one unaccounted internal source of the energy of tectonic processes

2013;
: pp. 298 - 300
https://doi.org/10.23939/jgd2013.02.298
Received: August 01, 2013
Authors:
1
Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences

The method of the research relates to the theoretical tectonophysics. We study the question of the sources of energy of tectonic processes in the crust and lithosphere. They is divided into internal and external. Internal sources include the processes associated with the inversion density created during sedimentation in horizontally stratified array, as well as resulting from thermal heating due to the approach to the base of the lithosphere of the anomalous mantle. These processes determine the instability of the state of the environment and its commitment due course move to a new stable state. In this paper we suggest another source of internal tectonic flow in the crust and lithosphere. It is energy elastic volume compression horizontally stratified array associated with the gravitational stress. In this case, the instability occurs at inversion depth elastic stiffness, i.e. when the overlying layers have higher bulk modulus. In mechanics known principle of minimum potential energy, which corresponds to the state of stress of a solid body under loading. For the potential energy in the event of action of mass forces include not only the elastic energy and the potential energy of the body in the gravitational field. The principle applies to lowest total energy emerging from the elastic deformation changes the volume and shape, as well as the potential energy of the body in the gravitational field. The deviation from the principle of minimum potential energy in the case of solid components with the viscous rheology leads to flow, the result of which is the transfer medium in a more stable state. The viscous flow is carried out due to the difference of the potential energies of the unstable and stable states.The object of research is the crustal rock for which one since some depths (3-5 km), the energy of the elastic volume changes caused by the action of gravity, begins to prevail over dramatically changing the shape of the elastic energy at the level of the middle crust (20 km) of the ratio becomes close to 10:1. The mantle is a ratio of greater than 100:1. Therefore, the average rock crust and mantle in the analysis of the potential energy necessary to talk about the changes in the volume of elastic energy and potential energy of the rock mass in a gravitational field. An important feature of the crystalline rocks of the crust is a small range of density of rocks, which fit into the change of 3-4%. Wherein the bulk modulus of different species may differ by an order or more. If the rock behaved like a perfect elastic body, does not have the shear stiffness (elastic fluid), the change in potential energy of the body in the gravitational field and the energy of the elastic volume changes during the course were always mutually offset (additional change of the potential energy is zero). But we know that the crustal rocks during deformation volume change is not only due to the elastic deformation, but also due to inelastic (dilatancy, compaction). This inelastic volume change is often the sign of the opposite elastic. In this paper we consider the extreme case, when during the course of the overall change in volume due to the elastic and inelastic deformation is zero. The results of our researches are shown, that at the same density layered array of its potential energy in the gravity field does not change. It is shown that in such an idealized layered array inversion depth of the bulk modulus is unstable Lagrange state, and the principle of minimum potential energy corresponds to the state of the array in which the depth is only observed an increase in the values of the bulk modulus.The novelty lies in the hypothesis of a possible application of layered rocks of the crust of the principle of minimum potential energy only to change the volume of the elastic energy of the gravitational stress. The practical significance is a fundamental change in the stability study of layered mountain ranges.

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