Strain and Mass Transport Associated with Ductile Exhumation of the Torlesse Accretionary Wedge

构造学中的一个基本问题是变质岩在会聚楔形体内的抬升和折返。特别令人感兴趣的是侵蚀与构造减薄的相对作用，在构造减薄中，减薄可以通过正常的断层作用和/或韧性流动发生。该项目将测量奥塔哥山脉顶端的有限变形，以了解侵蚀和楔形体内的韧性流动如何促进楔形构造的剥离。奥塔哥峰顶标志着新西兰托莱斯增生楔的弧前高，并得到了很好的研究。这些岩石保存在中白垩世准平原和较年轻地层的薄层覆盖之下，为识别较年轻变形的影响提供了依据。该地区的有限应变模式以及有关体积应变的信息将被用来解决白垩纪中期弧前高地的抬升和侵蚀速率问题。这些结果将为与其他收敛边际情况的比较提供一个有用的模型。

9814807Brandon A fundamental problem in tectonics is the uplift and exhumation of metamorphic rocks within convergent wedges. Of particular interest are the relative roles of erosion versus tectonic thinning, where thinning can occur by normal faulting and/or ductile flow. This project will measure finite deformation across the Otago culmination in order to understand how erosion and within-wedge ductile flow contribute to exhumation of the wedge. The Otago culmination marks the forearc high of the Torlesse accretionary wedge of New Zealand, and has been well-studied. The rocks are preserved beneath a middle Cretaceous peneplain and a thin cover of younger strata which provides a datum for identifying effects of younger deformation. The pattern of finite strain over the region, along with information about volume strains will be used to resolve middle Cretaceous uplift and erosion rates for the forearc high. These results will provide a useful model for comparison to other convergent margin situation.