Effect of Changing Basal Friction on the Formation of Thrust
The deformation problem of a wedge lying on a rigid base is considered. The effect of basal friction on the formation of thrusts is studied numerically. A model with a decreasing value of basal friction is proposed. The effect of clustering of areas with differently reduced friction was found. As a result, the friction coefficient changes periodically and it correlates with the formation of localized shear bands and stressed state. Zones with reduced friction correspond to areas with higher irreversible deformation and lower values of the ratio of \(\tau /p\). Thrust differences are shown in the case of constant and decreasing friction. In the first case, the faults are linear, and the topographic slope is consistent with the critical wedge theory. The faults have a list form when friction decreases during the deformation process. The greatest slope of the topographic surface is in the frontal zone, where shear deformation bands are formed. The slope of the topography becomes much less in the zones, where the slip occurs with low friction.
KeywordsBasal friction Thrust Plastic deformation Shear band Numerical modeling
The project was carried out within the frames of the project IX.128.1.1. Programs of Fundamental Scientific Research of State Academies of Sciences and with partial support (Sect. 3.2) of the Russian Foundation for Basic Research, grant №19-05-00378.
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