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

地球外层固体壳的广泛构造应力导致沿断裂带的局部变形。变形导致岩石位移，造山过程中热量和流体的大规模运动对岩石的埋藏、加热和潜在熔融作用起着重要的控制作用，对经济矿床和油气藏的分布起着关键作用。了解这些深时间构造事件的速度对于在较短的时间尺度上预测固体地球是至关重要的。在地球深处的高温下使岩石变形的过程被很好地描述了出来。然而，我们对岩石在地球表面出现的时间和速度知之甚少，也不知道变形途径对用于理解这一现象的同位素系统的影响。为了更好地解开这些时间之谜，需要对岩石穿过地壳时的热历史进行定量了解。这项研究计划通过推进创新的科学方法来解决这些需求，这些方法揭示了岩石在构造位移过程中温度、深度和变形状态随时间的变化。岩石的“旅行日志”是从矿物组合和纹理的详细化学和结构特征中收集的。总的来说，这些构成了地壳构造过程的指纹，并促进了我们对长期的地壳尺度过程如何与气候动力学、表面过程和地球固体内部联系在一起的认识。在发现基金的支持下，我的工作开启了地球科学研究的新阶段，涉及学生和合作者，开发创新的地质年代学技术，并奖励我的学生使用世界一流的仪器并进行培训。虽然研究的重点是山带生命周期等基础问题，但从亚微米尺度的同位素迁移到大尺度的构造运动，这些研究都对地球科学产生了影响。更直接的是，该研究在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油藏的埋藏历史。

Broad tectonic stresses over the Earth’s outer solid shell cause localized deformation along fault zones. Deformation leads to the displacement of rock, and this large-scale movement of heat and fluids during mountain building exerts a major control on the burial, heating, and potential melting of rock, and plays a key role in the distribution of economic ore deposits and hydrocarbon reservoirs. Understanding the tempo of these tectonic events across deep time is fundamental for making predictions about the solid Earth on shorter timescales. The processes that deform rocks at high temperatures deep in the Earth are reasonably well characterized. Little is known, however, of the timing and rate that rocks take to emerge at Earth's surface, nor the effects of the deformation pathway on the isotopic systems used to understand this phenomena. To better decipher these temporal riddles, a quantitative understanding of the thermal history of rocks as they move through the Earth’s crust 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 tectonic displacements. 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 the crust and advance our knowledge of how long-term, crustal-scale processes link to the dynamics of climate, surface processes and 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, including determining the timing and duration of ore-bearing fluid flow and the burial history of petroleum reservoirs.