EXPERIMENTAL STUDY OF FEATURES OF PREPARATION AND MOVEMENT ON A MODEL FAULT IN AN ELASTOVISCOPLASTIC MODEL OF THE LITHOSPHERE

Abstract

This paper presents the results of experiments to reproduce the process of stick-slip along a pre-existing stick-slip discontinuity in an elastoviscoplastic model. There are numerous examples of this process being reproduced experimentally to look for signs of the preparation of pulsed displacement along a fault, which could be interpreted as a harbinger of an impending earthquake in nature. In these experiments, rocks and other materials with high elasticity and susceptibility to brittle fracture were used as models. The results presented in this article were obtained using elastoviscoplastic models. The authors are not aware of the use of such models in the experiments described. The model materials were an aqueous paste of montmorillonite clay and wet river sand. As a result of the experiments, characteristic stages of deformation of the near fault zone were identified, one of which corresponds to slow sliding of the material with aperiodic displacement fluctuations. Digital image analysis was used to identify areas of both excess and deficient displacement along the strike of the model fault.