Shortening, Gravity-Driven Compensation, and the Thermal Evolution of the East Greenland Caledonides

小行星9526659 造山带内部的伸展变形过程在碰撞山脉的发育中具有重要意义。 首先在喜马拉雅有很好的记录，这些伸展结构似乎提供了一种机制，限制地形起伏和平均海拔时，物理侵蚀是不足以补偿的压缩驱动隆起。 通常与这些伸展特征相联系的是一种神秘的变质关系，其中变质等级是倒置的，即向上增加。 从热模拟可以清楚地看出，这些倒转的变质梯度只能通过快速冷却来保存。 然而，这些系统的变形（压缩与伸展去顶住宿）和地热预算（变质等级和压力-温度-时间路径）之间的时空和力学关系还没有得到很好的理解。 本项目将研究东格陵兰加里东地区的构造剥蚀和逆变质作用。 这一地区暴露了造山带更深的部分，反转变质梯度存在于与喜马拉雅山类似构造不同的构造环境中。 从技术上讲，所使用的高精度地质年代学技术能够更密切地联系这一较老造山带中的变形变质作用。 这项研究的预期结果包括更好地了解活动变形造山带的热行为，特别是在整个挤压造山带的伸展事件。

9526659 Hodges The process of extensional deformation within orogenic belts is of considerable interest in the development of collisional mountain ranges. First well-documented in the Himalaya, these extensional structures appear to provide a mechanism for limiting the topographic relief and mean elevation when physical erosion is not sufficient to compensate for the compression-drives uplift. Commonly associated with these extensional features is an enigmatic metamorphic relationship in which the metamorphic grade is inverted, that is, increases upward. From thermal modeling it is clear that these inverted metamorphic gradients can only be preserved with rapid cooling. However, the temporal spatial and mechanical relationships between deformation (compression with extensional unroofing accommodation) and the geothermal budget (Metamorphic grade and pressure-temperature-time path) of these systems is not well understood. This project will study tectonic denudation and inverted metamorphism in the East Greenland Caledonides. This area exposes a much deeper part of an Orogen, and the inverted metamorphic gradient is present in a different structural setting from analogous structures in the Himalaya. Technically, the high-precision geochronologic techniques to be used are capable of more closely tying deformation metamorphism in this older orogen. The expected results of this research include a better understanding of the thermal behavior of actively deforming orogens, particularly in response to episode of extension in the overall compressional orogens.