Applied thermochronology and the isotopic record of low-temperature crustal-scale tectonic processes

山脉带以多种方式形成，但最常见的两个末端是通过挤压(压缩)和拉伸(伸展)地壳。发现号研究计划的一个特别重点是针对山脉地带的核心，那里发生了大部分地壳热量和物质的运输。解决岩石在这些环境中的热演化问题，直接影响到地球动力学、气候和景观演化模型的发展。在高温下在山区形成岩石的过程被合理地描述得很好。然而，关于岩石出现在地球表面所需的时间尺度，以及变形路径对同位素系统的影响，人们知之甚少。为了更好地理解这些过程，需要对岩石在一系列地质环境下穿过地球外壳时的热演化有一个定量的了解。这项研究建议通过推进创新的科学方法来满足这些需求，这些方法揭示了岩石在山脉生长和衰变期间随时间的温度、深度和变形状态的变化。岩石的“旅行日志”是从矿物组合和结构的详细化学和结构特征中收集的。总而言之，这些构成了在山脉中工作的构造过程的指纹，并促进了我们对长期的地壳规模的过程如何与气候动态、表面过程和地球固体内部的联系的了解。在探索基金的支持下，我的工作开始了一个涉及学生和合作者的地球科学研究的新阶段，开发创新的地质年代学技术，并奖励我的学生获得世界级仪器并进行培训。尽管这项研究集中在山带生命周期等基本问题上，但通过地球科学产生了影响，从亚微米级的同位素流动性到大规模的构造作用。更直接的是，这项研究在加拿大境内的自然资源勘探中具有特定的应用，包括确定含矿流体流动的时间和持续时间，以及石油储集层的埋藏史。

Mountain belts form in many ways but the two most common end-members are through squeezing the Earth's crust (compression) and stretching it (extension). A particular focus of this Discovery research program is aimed at the cores of mountain belts where most of the transport of crustal heat and mass occurs. Resolving a rock's thermal evolution in these settings has direct influence on the advancement of geodynamic, climate, and landscape evolution models. The processes that form rocks at high temperatures in mountain belts are reasonably well characterized. Little is known, however, of the timescales that rocks take to emerge at the Earth's surface, nor the effects of the deformation pathway on the isotopic systems. To better understand these processes, a quantitative understanding of the thermal evolution of rocks as they move through the Earth's outer shell and under a range of geologic settings is required. This research proposal addresses these needs by advancing innovative scientific approaches that shed light on rock's change in temperature, depth and deformation-state through time during mountain growth and decay. The rock's "travel log" is gleaned from detailed chemical and structural characterization of mineral assemblages and textures. Collectively, these make up the fingerprint of the tectonic process at work in mountains and advance our knowledge of how long-term, crustal-scale processes link to the dynamics of climate, surface processes and the Earth's solid interior. Together with Discovery Grant support, my work embarks upon a new phase of Earth science research involving students and collaborators, developing innovative geochronology techniques, and rewarding my students with having access to, and training on, world-class instruments. Although concentrating on fundamental issues such as the life cycle of mountain belts, this research has impacts through the Earth Sciences, from submicron-scale isotope mobility to mega-scale tectonism. More directly, this research has specific applications to natural resource exploration within Canada, including determining the timing and duration of ore-bearing fluid flow and the burial history of petroleum reservoirs.