Computer modelling of the state of stress and strain of the Tunguska and Vilyui syneclises

A. Zh. Akhmetov ; I. Yu. Smolin

Vestnik Tomskogo gosudarstvennogo universiteta. Matematika i mehanika, no. 75 (2022), pp. 52-66

Résumé

The states of stress and strain are numerically analyzed under conditions of the geodynamic process of tension in the south part of the Vilyui syneclise and the middle part of the Tunguska syneclise. Two-dimensional models of geological structures of the south part of the Vilyui syneclise and the middle part of the Tunguska syneclise are constructed based on the Kimberlit-1981 geological profile obtained using deep seismic sounding. To describe the plastic strain in the geomedia, the model of elastic-plastic media with the non-associated plastic flow rule based on the Drucker-Prager-Nikolaevskii model is used. In this model, the “jelly sandwich” strength model is adopted for the analysis of the stress state of the lithosphere. The results of the numerical modeling of the state of the stress and strain of the chosen parts of the Siberian Craton are presented. The localization of plastic strain, the region of positive values of horizontal stresses, and the negative deviation of the calculated pressure from the lithostatic pressure correspond to mineral deposits.

Détail

Keywords: stresses and strain allocation, numerical modelling, finite difference method, continental lithosphere, elastic-plastic media, Vilyui syneclise, Tunguska syneclise, “jelly sandwich” model, Kimberlit-1981 geological profile.