Analysis of results of interpretation of elastic parameters of solid core of the Earth from the standpoint of current geomechanics
Journal Title: Геофизический журнал - Year 2017, Vol 39, Issue 1
Abstract
It follows from the basic principles of mechanics of deformable solids relating to the strength, stability and propagation of elastic waves that the inner core of the Earth cannot exist in the form of a spherical structure in the assumed thermobaric conditions and calculation values of physico-mechanical parameters. Pressure level reaches a value that is significantly greater than the theoretical limit of medium strength in the model approximations at the surface of the sphere of the inner core. On the other hand, equilibrium state of the sphere is unstable by the geometric forming at much lower loads under the influence of the "dead" surface loads. In case of the action of "follower" loads, the assumed pressure value on the surface of the sphere is comparable with the value of the critical load of "internal" instability. In these cases, due to the instability of the equilibrium state, propagation of homogeneous deformations becomes uneven in the sphere. Moreover, the elastic waves with actual velocity cannot propagate in such conditions in solid medium. Violation of these fundamental conditions of mechanics needed in determining the physical and mechanical properties of the medium must be taken into account in the integrated interpretations of seismic and laboratory (experimental) data. In this situation, application of linear elasticity theory and elastic waves, despite compliance with the required integral conditions on the mass, moment of inertia and natural oscillations of the Earth, does not ensure the reliability of results on the structure and composition of the Earth's core.
Authors and Affiliations
H. H. Guliyev
Special features of distribution of seismic waves propagation velocity in the Earth crust in the area of uranium deposits (Kirovograd ore area of Ingul megablock of the Ukrainian Shield)
Principal possibility of detailed study of velocity characteristics of crystalline Earth crust in the areas of uranium deposits has been shown. By comparison with geologic data an assumption has been expressed on increas...
Lithospheric structure based on integrated analysis of geological-geophysical data along the DOBREfraction’99/DOBRE-2 profile (the East European Platform —the East Black Sea Basin)
The continuous DOBREfraction’99/DOBRE-2 WARR and CDP profile of 775 km length with about 100 km overlap was acquired by an international team from Ukraine, Poland, Denmark, USA, Netherlands, Germany, Great Britain and No...
Earth’s crust composition of the Ingul megablock of the Ukrainian Shield (types of crust) and patterns of location of ore mineral resources
Within the Ingul Megablock of the Ukrainian Shield, according to the data of three-dimensional density modeling, at the scale of 1 : 200 000, the thickness of conditionally allocated “granite”, “diorite”, “basalt” layers...
Petroleum potential of Lower Jurassic and Pre-Jurassic reservoirs of Ust-Tym mega depression
The relevance of the research is caused by the need of reproduction of oilfields area resource base in southeast of Western Siberia. The main aim of the research is to identify and to propose the priority areas for explo...
Fractional dynamics and emissive activity of geosystems
Some particular problems and nonstandard ideas, reflecting up-to-date state of nonlinear- dynamic approach to the studies of geosystems are under consideration. Attention is concent¬rated on the mechanisms of generation...