Interaction of folding and thrusting during fold-and-thrust-belt evolution: Insights from numerical simulations and application to the Swiss Jura and the Canadian Foothills
Interaction of folding and thrusting during fold-and-thrust-belt evolution: Insights from numerical simulations and application to the Swiss Jura and the Canadian Foothills
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褶皱冲断带演化过程中褶皱和冲断的相互作用：数值模拟及其在瑞士侏罗山和加拿大山麓应用的见解
DOI：
10.1016/j.tecto.2020.228474
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发表时间：
2020
期刊：
影响因子：
2.9
通讯作者：
Schmalholz Stefan M.
中科院分区：
文献类型：
--
作者：
Humair Florian;Bauville Arthur;Epard Jean-Luc;Schmalholz Stefan M.
利用二维数值模拟方法研究了褶皱-冲断带构造演化过程中褶皱（屈曲）和冲断（局部剪切）的相互作用。我们模型层平行缩短机械强层休息上面的一个较弱的层，称为脱离。考虑了具有线性粘度和摩擦塑性Drucker-Prager屈服准则的粘塑性流变学。模型一半的滑脱厚度较大，只有这种几何厚度扰动才能在模拟中触发褶皱和逆冲。我们进行了系统的分析，以量化模型参数的影响，如厚度扰动或剥离流变学（摩擦或粘性）的大小，对FTB的演变。扰动的大小决定了褶皱作用是否优于逆冲作用，从而控制了褶皱和逆冲作用在FTB演化过程中的相互作用。模拟的背斜的不对称性与初始扰动的相对高度成正比。我们还适应模型配置，以特定的机械地层的两个地区的自然FTB，即上夏讷的汝拉山（瑞士）和山麓的阿尔伯塔（加拿大）。模拟的褶皱和逆冲断层的几何形状与不同类型的观察到的背斜结构，如对称的逆冲断层褶皱和不对称的逆冲断层褶皱。我们的研究结果表明，低幅度屈曲的初始阶段可能发生在主褶皱和逆冲阶段之前。我们认为，褶皱和逆冲作用是同样重要的和相互作用的过程中，许多天然FTB的结构演化。
We use two-dimensional numerical simulations to investigate the interaction of folding (buckling) and thrusting (localized shearing) during the structural evolution of fold-and-thrust belts (FTB). We model layer-parallel shortening of mechanically strong layers resting above a weaker layer, referred to as detachment. We consider a viscoplastic rheology with linear viscosity and frictional-plastic Drucker-Prager yield criterion. The detachment thickness is larger in one model half and only this geometrical thickness perturbation triggers folding and thrusting in the simulations. We conduct a systematic analysis to quantify the impact of model parameters, such as magnitude of the thickness perturbation or detachment rheology (frictional or viscous), on the FTB evolution. The magnitude of the perturbation determines whether, or not, folding is favoured over thrusting and, hence, controls the progressive interaction of folding and thrusting during FTB evolution. The asymmetry of modelled anticlines is proportional to the relative height of the initial perturbation. We also adapt the model configuration to specific mechanical stratigraphies of two regions in natural FTB, namely the Haute-Chaîne of the Jura Mountains (Switzerland) and the Foothills of Alberta (Canada). The modelled fold and thrust geometries agree with different types of observed anticlinal structures, such as symmetric detachments folds and asymmetric thrust-folds. Our results suggest that an initial stage of low-amplitude buckling likely occurred prior to the main folding and thrusting phase. We argue that folding and thrusting are equally important and interacting processes during the structural evolution of many natural FTB.
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影响因子：
4.2
作者：
J. Ruh;B. Kaus;J. Burg
通讯作者：
J. Ruh;B. Kaus;J. Burg
瑞士-意大利阿尔卑斯山西部的地质格架和结构演化
DOI：
10.1007/978-3-0348-9098-4_16
发表时间：
1995
期刊：
Eclogae Geologicae Helvetiae
影响因子：
--
作者：
A. Escher;J. Hunziker;M. Marthaler;H. Masson;M. Sartori;A. Steck
通讯作者：
A. Steck
阿尔卑斯型覆盖层的数值模型
影响因子：
2.9
作者：
S. Wissing;S. Ellis;O. Pfiffner
通讯作者：
O. Pfiffner
脱扣折叠作为推力坡道间距的机制
影响因子：
--
作者：
D. Goff;D. Wiltschko;R. C. Fletcher
通讯作者：
R. C. Fletcher
Jura 褶皱肢体旋转期间的几何调整
影响因子：
2.9
作者：
H. Laubscher
通讯作者：
H. Laubscher