The report considers the mathematical modeling of the conditions of formation of dome structures in stratum competent and uncompetent layers under the influence of longitudinal tectonic forces. The original structures are connected with non-homogeneity stratum and irregular distribution of the forces. It is reduced to the solution of the problem of local instability for the stratum in boundary of some competent layer. Adjacent equilibrium forms for the layer are investigated and the convexity and concave parts determined by the form of the domain are found. The convexity parts are considered as embryo of domes. The observed difference of forms, dimensions and deflections of the folds are explained. The reaction of the uncompetent layers is striated; it is shown that viscosity does not influence the value of folding forces. The calculations show that dome folding is originated by forces with an order of 10**5 newton/m**2. The following growth of it is considered as a finite deflection of the equivalent viscoelastic layer in the medium with mean viscosity. The solution of the obtained nonlinear equation as well as qualitative study on the phase show that closure velocity increases from the certain value for given physical and geometrical conditions after which it begins to slow down. The generation of the dome for the geosyncline is explained with the help of the mechanism of imposition of linear folds with different age and without reorientation of the tectonic forces. The calculations have shown the reality of this imposition.
|Publication status||Published - 1 Jan 2017|