Pure and applied problems in metamorphic geology

加拿大一半以上的陆地表面是变质岩和火成岩，到目前为止，加拿大大部分的矿藏都在这些地区。因此，了解变质岩和火成岩是如何形成的具有科学和社会意义。我的研究项目是关于变质关系的一半，即变质岩石学（变质岩的组成和成因的科学研究）。变质岩学是研究板块构造相互作用引起的地壳埋藏、加热和掘出的主要学科。当与构造、地质年代学和热年代学技术相结合时，变质岩石学有助于揭示地球板块构造相互作用的演变，并为矿床的形成和改造提供信息。地球科学其他领域（构造学、构造学、矿床学）的研究人员依赖于变质岩石学家通过阅读变质岩石记录提供的压力（深度）和温度（P和T）的估计。如果提供的估计数不准确，就会使所有这些领域的进展倒退。因此，我的研究计划的长期目标有两个方面：(1)提高我们对变质再结晶的理解，目的是提高我们对变质岩石压力（深度）和温度估计的可靠性；(2)将这种增强的认识与相关技术相结合，以深入了解地球造山带（山脉）的演化，特别是加拿大南部的科迪勒拉山脉。每一个目标都会刺激另一个目标的进步。提出的短期目标包括：（1-1）建立一个来自世界各地不同P和T变质环境的天然矿物组合和矿物成分数据库，并使用这些数据库来测试和完善这些关系的热力学模型；（1-2）绘制了苏格兰巴罗带第一张综合矿物组合图，巴罗带可以说是地球上最著名、研究最多的变质层序；（1-3）评价由变质岩相平衡分析推断出的变质作用深度的可靠性；（1-4）分析岩石变形对变质再结晶的催化程度；（2-1）确定不列颠哥伦比亚省Shuswap地区Valhalla杂岩的演化，这是一个核心杂岩的“典型例子”（=由断层包围的中深部地壳岩石的“隆起”，这种情况在世界各地的伸展性海洋和大陆环境中都有发现）。从培训的角度来看，参与这项研究将教育下一代地球科学家，为他们提供在学术界，政府和工业界高度重视的观察，分析，计算，解释和沟通技能。他们将成为加拿大需要的适应性强、跨学科的下一代地球科学家的先锋。

Over half of Canada's land surface is underlain by metamorphic and igneous rocks, and by far the majority of Canada's mineral deposits occur in these areas. Understanding how metamorphic and igneous rocks form is thus of scientific and societal interest. My research program is concerned with the metamorphic half of the relationship, namely metamorphic petrology (= the scientific study of the make-up and genesis of metamorphic rocks). Metamorphic petrology is the primary probe of the burial, heating and exhumation of Earth's crust arising from plate tectonic interactions. When combined with structural, geochronological and thermochronological techniques, metamorphic petrology helps unravel the evolution of Earth's plate tectonic interactions through time, and informs the formation and modification of mineral deposits. Researchers in other fields of geoscience (structure, tectonics, ore deposits) rely on the estimates of pressure (depth) and temperature (P and T) that metamorphic petrologists provide from reading the metamorphic rock record. If inaccurate estimates are provided, it sets back advances in all these areas. The long-term objectives of my research program are thus two-fold: (1) to advance our understanding of metamorphic recrystallization, the aim being to enhance the reliability of our estimates of pressure (depth) and temperature of metamorphosed rocks; and (2) to apply this enhanced understanding in concert with allied techniques to provide insights into the evolution of Earth's orogenic (mountain) belts, especially the southern Canadian Cordillera. Each objective stimulates progress in the other. Proposed short-term objectives include: (1-1)Creating a database of natural mineral assemblages and mineral compositions from metamorphic settings of varying P and T from around the world, and using these to test and refine our thermodynamic modelling of these relationships; (1-2)Creating the first comprehensive mineral assemblage map of Barrow's Zones in Scotland, arguably the most famous and most studied metamorphic sequence on Earth; (1-3)Assessing how reliable are the depths of metamorphism that are inferred from phase equilibrium analysis of metamorphic rocks; (1-4)Analyzing the degree to which rock deformation catalyzes metamorphic recrystallization; and (2-1)Determining the evolution of the Valhalla complex, Shuswap domain, British Columbia, a "type example" of a core complex ( = an "uplift" of mid-deep crustal rocks bounded by faults, such found in extensional oceanic and continental settings around the world). From a training perspective, engagement in this research will educate the next generation of geoscientists, providing them with observational, analytical, computational, interpretational and communication skills that are highly valued in academia, government and industry. They will be in the vanguard of the future generation of adaptable, interdisciplinary geoscientists Canada needs.