Structure of the Southern Province, Canadian Shield, inferred from scaled 3-D analogue modelling using viscous and granular materials

1.85 Ga的萨德伯里火成杂岩位于加拿大地盾的南部省，特别是在东佩诺克造山带（EPO）和钴板块之间的交界处。该杂岩是古元古代造山作用期间，因逆冲和褶皱作用而发生几何变化的最初水平碰撞熔融岩片的遗迹。一致的NW-SE缩短下SIC的非圆柱形折叠的原因是未知的。解开这个折叠的运动学需要了解EPO中圆柱形结构的产生，相比之下，钴矿板块中的圆顶和盆地。为了解决这些地区的规模上的结构的演变，模拟实验，使用分层的粘性和粒状材料的密度，粘度和厚度的主要岩性单元的建议。实验装置的设计将考虑到古元古代变形的运动学边界条件和个别岩石单元的变形前几何形状对结构演化的影响。在模型造山带中观察到的结构的几何形状将与在自然原型中观察到的结构进行定量比较。穹隆盆地构造是造山带中普遍存在的一种构造样式，但在运动学上对它的认识却很少。

The 1.85 Ga Sudbury Igneous Complex is located in the Southern Province of the Canadian Shield, specifically at the junction between the Eastern Penokean Orogen (EPO) and the Cobalt Plate. The complex is the relic of an originally horizontal impact melt sheet that was geometrically modified by thrusting and folding during Paleoproterozoic orogenesis. The cause for non-cylindrical folding of the SIC under uniform NW-SE shortening is unknown. Unravelling the kinematics of this folding requires an understanding of the generation of cylindrical structures in the EPO and, by contrast, of domes and basins in the Cobalt Plate. In order to resolve the evolution of structures on the scale of these regions, analogue experiments using layered viscous and granular materials scaled to density, viscosity and thickness of major lithological units are proposed. Experimental set-ups will be designed to take into account kinematic boundary conditions of Paleoproterozoic deformation and the influence of the predeformational geometry of individual rock units on the evolution of structures. The geometry of structures observed in model orogens will be quantitatively compared to those observed in the natural prototype. Elucidating the formation of dome-and-basin structure, an ubiquitous, yet kinematically little understood structural pattern in orogenic belts of all ages, is of general geodynamic importance.