Thrust faulting has been studied within the framework of a tectonic wedge model. A variant of the model was proposed which accounts for changing friction between the wedge bottom and a rigid foundation during irreversible deformation. Some specific deformation structures typical for thrust zones were revealed; their formation conditions were estimated. The range of friction coefficient values was determined in which the friction coefficient has a general effect on thrust structures. The nucleation sites and the main patterns of fault structures were described depending on the parameters of the medium and friction conditions at the bottom. The shear bands can initiate both from the layer bottom and from the surface, at irregularities of the relief, as well as at the front of the plastic deformation zone. It was found that listric faults initiate at the layer bottom in a medium with low shear strength. In a high strength medium, shear banding starts from the wedge surface. The calculations showed that the main factors determining the overall pattern of the deformation structure and fault structure in the thrust zone are the strength characteristics of the medium and friction between the deformed layer and the rigid foundation. The deformation processes were modeled by solving a system of dynamic equations of an elastoplastic medium using an explicit numerical scheme under plane strain. The behavior of the medium was described by a model with the Drucker—Prager yield surface and non-associated flow rule, with account for hardening and softening of the medium during plastic deformation.

中文翻译：

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介质的摩擦和强度特性对冲断结构中剪切带形成的影响

已经在构造楔模型的框架内研究了逆冲断层作用。提出了模型的一个变体，它解释了在不可逆变形过程中楔形底部和刚性基础之间的摩擦变化。揭示了逆冲带的一些典型变形结构；估计了它们的形成条件。确定摩擦系数值的范围，其中摩擦系数对推力结构有一般影响。根据介质参数和底部摩擦条件描述了断层结构的成核位置和主要模式。剪切带可以从层底部和表面、起伏不规则处以及塑性变形区的前部开始。研究发现，在低剪切强度的介质中，层状断层始于层底。在高强度介质中，剪切带从楔形表面开始。计算表明，决定逆冲带变形构造和断层构造整体格局的主要因素是介质强度特性和变形层与刚性地基之间的摩擦力。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。在高强度介质中，剪切带从楔形表面开始。计算表明，决定逆冲带变形构造和断层构造整体格局的主要因素是介质强度特性和变形层与刚性地基之间的摩擦力。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。在高强度介质中，剪切带从楔形表面开始。计算表明，决定逆冲带变形构造和断层构造整体格局的主要因素是介质强度特性和变形层与刚性地基之间的摩擦力。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。计算表明，决定逆冲带变形构造和断层构造整体格局的主要因素是介质强度特性和变形层与刚性地基之间的摩擦力。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。计算表明，决定逆冲带变形构造和断层构造整体格局的主要因素是介质强度特性和变形层与刚性地基之间的摩擦力。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。变形过程是通过在平面应变下使用显式数值方案求解弹塑性介质的动力学方程组来建模的。介质的行为由具有 Drucker-Prager 屈服面和非关联流动规则的模型描述，其中考虑了塑性变形过程中介质的硬化和软化。