Supplementary material for analogue experiments on the interactions of two indenters, and their implications for curved fold-and-thrust-belts

This data publication includes animations and figures of eight scaled analogue models that are used to investigate the evolution of a curved mountain belt akin to the Pamir and Hindu Kush orogenic system and adjacent Tadjik basin. Crustal deformation is simulated by means of indentation of two basement blocks into a sedimentary sequence and the formation of a curved fold-and-thrust belt.The experimental set-up has two adjacent rigid indenters representing the basement blocks moving in parallel with a velocity difference (Figure 1). The slow indenter moves with a relative velocity ranging from 40 to 80% of that of the fast one. A layer of quartz sand in front of the indenters, 1 by 1 meter in size and 1.5 cm thick, represents the sedimentary basin infill. A basal detachment layer is made up of low-friction glass beads or viscous silicone oil representing weak shale or evaporates layers, respectively. The surface evolution by means of topography and strain distribution is derived from 3-D particle image velocimetry (PIV). This allows visualizing and analysing the development of the model surface during the complete model run at high spatio-temporal resolution. All details about the model set-up, modelling results and interpretation can be found in Reiter et al. (2011).The here provided additional material includes time-lapse movies showing the topographic evolution of the eight models. These visualizations are oblique views played back at 60-fold velocity for the “glass beads experiments” (gb40 to gb80) and 3600-fold velocity for the “silicone experiments” (si60, si-gb60).In addition to the experiment movies we provide a set of figures. The figures include surface views as well as cross-sections through the finite models highlighting the link between topography and internal structure of the simulated curved fold-and-thrust belts. Additionally, attribute maps of distinct morphometric measures (curvature, slope) and deformation parameters (uplift, horizontal translation) for the experiments with glass beads detachments are given. Finally, the movie “Experimenting.avi” shows in time-lapse the whole workflow of setting up, conducting and documenting an experiment, which originally required three days (for experiment si-gb60).An overview on the parameters used in the experimental series of the movie sequences is given in the explanatory file (Explanations_Reiter-et-al-2016.pdf). A full list of files is given in “list-of-files-Reiter-et-al-2016.pdf”.

本数据集包含8个缩尺相似模拟实验的动画与图件，这些实验旨在探究类似帕米尔-兴都库什造山带及邻区塔吉克盆地的弧形造山带演化过程。实验通过将两个基底块体挤入沉积序列，模拟地壳变形并形成弧形褶皱-冲断带。实验装置包含两个相邻的刚性挤压器（代表基底块体），二者沿平行方向运动且存在速度差（见图1），其中慢速挤压器的相对速度为快速挤压器的40%~80%。挤压器前方铺设有一层尺寸为1m×1m、厚度1.5cm的石英砂，用以模拟沉积盆地充填物。基底滑脱层分别由低摩擦玻璃珠或粘性硅油构成，分别对应软弱页岩层与蒸发岩层。实验通过三维粒子图像测速技术（3-D particle image velocimetry, PIV）获取地形与应变分布，以此反演表面演化过程，该技术可在高时空分辨率下，对完整实验周期内的模型表面发育过程进行可视化与分析。有关实验装置设置、模拟结果及解释的全部细节，可参见Reiter等人（2011）的研究。

本数据集附带的补充材料包含8个实验的地形演化延时视频，均采用斜视角画面：其中“玻璃珠实验”（gb40至gb80）以60倍速回放，“硅油实验”（si60、si-gb60）则以3600倍速回放。除实验视频外，本数据集还提供一组图件，包含实验表面视角图与最终模型的剖面示意图，用以阐明模拟弧形褶皱-冲断带的地形与内部构造之间的关联。此外，还提供了采用玻璃珠作为滑脱层的实验的多项形态计量参数（曲率、坡度）与变形参数（抬升量、水平位移量）的属性分布图。最后，视频文件“Experimenting.avi”以延时方式展示了实验的完整流程，包括装置搭建、实验开展与数据记录，该流程在实际开展si-gb60实验时原本需要耗时三天。

实验序列的参数概述可参见说明文件《Explanations_Reiter-et-al-2016.pdf》；全部文件清单则收录于《list-of-files-Reiter-et-al-2016.pdf》。