Structural Changes in Minerals and their Effect on Intrinsic Properties

我的研究程序考察了矿物行为(物理、机械、热力学、弹性和化学性质)作为压力(P)、温度(T)、成分(X)和时间(T)的函数，即P-T-X-t条件。矿物行为为地球过程提供了现实的模型，因为矿物的性质由它们的晶体结构决定。在我的小组中，我们试图回答这样的问题，例如为什么固体材料具有它们所展示的组成、结构和性质？这些特性在不同的P和T条件下是如何变化的？结构中原子的有序性如何随着P-T-X-t条件的变化而变化？我们使用各种现场实验技术来研究在环境和非环境(不同的P和T)条件下控制矿物稳定性和性质的过程，并将结果应用于矿物物理和地球过程。我们在大学实验室以及同步加速器和中子设施中使用实验技术。我的小组成员研究引起科学界极大兴趣的矿物，因为它们的技术特性和它们在了解地球过程中的有用之处。例如，石榴石类矿物很重要，因为它们在一系列P-T-X-t条件下赋存，并保存了有关火成岩和变质过程的重要记录。石榴石类矿物在激光和汽车电池中有重要用途。一些石榴石是分区的，这会影响它们的性质。在长石和大约75种其他矿物中，成分分带是众所周知的，所以我们的工作将对许多矿物产生影响。矿物中的分带必须考虑到它们的热力学行为，以及它们在地温测量、地球重力测量和地质年代学中的有效使用。此外，无序过程会影响地震速度，这是地球物理模型所必需的。我的HQP将学习重要的技术来解决矿物学、结晶学和材料科学领域的问题。我们的发现有可能导致重大发现，使加拿大经济受益。

My research program examines mineral behaviour (physical, mechanical, thermodynamic, elastic, and chemical properties) as a function of pressure (P), temperature (T), composition (X), and time (t), that is, P-T-X-t conditions. Mineral behaviour provides realistic models for Earth processes because mineral properties are governed by their crystal structure. In my group, we try to answer questions such as why do solid materials have the composition, structure, and the properties that they exhibit? How do these properties change under different P and T conditions? How does the ordering of atoms in a structure change in response to P-T-X-t conditions? We use various in situ experimental techniques to investigate the processes that govern mineral stabilities and properties under ambient and non-ambient (different P and T) conditions and apply the results to Mineral Physics and Earth processes. We use experimental techniques in university laboratories and at synchrotron and neutron facilities. My group members investigate minerals that receive significant interest to the scientific community because of their technological properties and their usefulness in understanding earth processes. For example, garnet-group minerals are important because they occur over a range of P-T-X-t conditions and they preserve important records of igneous and metamorphic processes. Garnet-group minerals have important uses in lasers and automotive batteries. Some garnets are zoned, which affect their properties. Compositional zoning is well known in feldspars and about 75 other minerals, so our work will have implications for numerous minerals. Zoning in minerals must be considered in their thermodynamic behaviour and their effective use in geothermometry, geobarometry, and geochronology. Moreover, order-disorder processes affect seismic velocities and are needed for geophysical models. My HQP will learn important techniques to solve problems in the fields of mineralogy, crystallography, and materials science. Our findings have the potential to lead to significant discoveries that will benefit the Canadian economy.