A Theoretical Basis for Mineralogy and the Behaviour of Minerals in Earth Processes

矿物学和矿物在地球过程中的行为的理论基础

• 批准号: RGPIN-2020-05675
• 负责人: Hawthorne, Frank
• 金额: $ 2.19万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=740778
• 关键词: Theoretical; Basis; Mineralogy; Behaviour; Minerals

Minerals are the fundamental materials of the Earth, and if we wish to understand the processes which formed the Earth, and which continue to modify its landscape and the human environment, we need to understand the behaviour of minerals under the full spectrum of conditions experienced on Earth. This proposal focuses on a wide variety of minerals in an attempt to understand the atomic-scale factors affecting their constitution and behaviour, and to use this understanding to rationalize and predict their behaviour at the macroscopic scale. I use various forms of radiation (X-rays, neutrons) to 'see' into a mineral at the atomic scale via diffraction, and to derive the arrangement of atoms from which it is built. Details concerning atomic disorder can be seen with spectroscopy using other forms of radiation (e.g. infrared, gamma rays). The resulting atomic-scale details of the mineral give us the information from which we can understand aspects of how and at what conditions the mineral formed, and under what conditions it is stable. Why do minerals have the chemical formulae that they do? Why do they have their specific structural arrangements? Why are minerals stable over specific ranges of pH, Eh, temperature, pressure and constituent activities? What are the relations between crystal structure and enthalpy, entropy and Gibbs free energy of formation? How can we derive the atomic-scale mechanisms of geological processes? What is the relation of mathematical complexity to mineral structures and the behaviour of minerals in equilibrium and non-equilibrium processes? These questions are fundamental to Mineralogy itself and yet have been ignored in the past because they are not susceptible to established theoretical techniques in Physics and Chemistry. The work proposed here addresses several of these problems from a fundamental perspective, and will further our understanding of different Earth materials and the way that they respond to changes in their environment. A major part of this proposal involves the further development of a theoretical approach to answering these questions, an approach based on the topology (connectivity) of chemical bonds in space. I will use various aspects of Mathematics (Graph Theory, Combinatorial Topology, Complexity Theory) and Chemistry (the moments approach to the energy density-of-states of solids) to [1] develop connections between patterns of bond connectivity (bond topology) and their energetic content; [2] examine how these connections dictate the chemical compositions and structural connectivities of minerals; and [3] how these factors affect how minerals participate in geological processes. This theoretical work is supported by an extensive experimental program of mineral characterization involving amphiboles and tourmalines, gem minerals, TS-block minerals, new minerals, and other diverse projects that can benefit from our local experimental capabilities and theoretical expertise.

矿物质是地球的基本材料，如果我们希望了解形成地球的过程，并继续修改其景观和人类环境，我们需要了解在地球上经历的各种条件下矿物的行为。该提议着重于各种矿物质，以了解影响其宪法和行为的原子规模因素，并利用这种理解来合理化和预测其行为，以宏观的规模。我使用各种形式的辐射（X射线，中子）通过衍射将原子尺度的矿物“看到”，并得出构建原子的原子的排列。使用其他形式的辐射（例如，红外，伽马射线）可以通过光谱法观察有关原子障碍的细节。矿物的最终原子尺度细节为我们提供了信息，我们可以从中了解矿物形成的条件以及在哪种条件下的稳定条件下的各个方面。为什么矿物具有化学公式？他们为什么要有特定的结构安排？为什么矿物质在pH，EH，温度，压力和成分活性的特定范围内保持稳定？晶体结构与焓，熵和吉布斯自由能之间的关系是什么？我们如何得出地质过程的原子级机制？数学复杂性与矿物结构的关系以及矿物在平衡和非平衡过程中的行为是什么？这些问题对矿物学本身至关重要，但过去却被忽略了，因为它们不容易受到物理和化学方面的理论技术的影响。这里提出的工作从基本的角度解决了这些问题，将进一步了解我们对不同地球材料的理解以及它们对环境变化的反应方式。该提案的主要部分是进一步发展理论方法来回答这些问题，这是一种基于空间中化学键拓扑（连通性）的方法。我将使用数学的各个方面（图理论，组合拓扑，复杂性理论）和化学（固体能量密度 - 固体的矩方法）来[1]发展键连接性（债券拓扑）与其能量含量之间的连接； [2]检查这些连接如何决定矿物质的化学成分和结构连接性； [3]这些因素如何影响矿物如何参与地质过程。这项理论工作得到了广泛的矿物质表征实验计划的支持，该计划涉及两性矿物质，宝石矿物质，TS-Block矿物质，新矿物质以及其他可以从我们本地的实验能力和理论专业知识中受益的各种项目。