Accessory mineral geochemistry in high-T systems

高温系统中的辅助矿物地球化学

• 批准号: 312462-2006
• 负责人: Cox, Richard
• 金额: $ 1.45万
• 依托单位: Université du Québec à Chicoutimi
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=365363
• 关键词: Accessory; mineral; geochemistry; systems

The Problem: Incompatible trace-element patterns (e.g. REE) are commonly used to model processes in high-temperature geologic systems. However, accessory minerals such may control incompatible trace-element distributions. Thus, understanding the link between the geochemistry of trace-elements and accessory minerals is crucial when applying geochemical modeling to geologic processes. The Objectives: To understand the geochemical influence of accessory minerals on whole-rock patterns in high-temperature geological systems. This will begin by focusing on an initial examination of crustal melt formation and the distribution of various accessory minerals and incompatible trace-elements between the parent rocks of different compositions and the resulting melts. The geochemical evolution of incompatible elements in large magmatic intrusions will also be studied to provide a database of accessory mineral compositions to augment and expand trace-elements databases which currently only exist only for zircon and apatite. This will allow a better comparison of the results of this research with established models for accessory mineral geochemistry and incompatible trace-element behavior in both magmatic and high-temperature metamorphic systems. Methodology: The proposed research will develop and apply micro-analytical techniques to meet the proposed research objectives using existing and newly developed ICP-MS techniques, centered around a new facility at the University du Québec a Chicoutimi. Excellent field study areas at Cap à l'Aigle and St. Fulgence, Québec have been identified and will provide access to a wide variety of parent rock and melt types. Significance: Linking the trace-element geochemical record with accessory mineral distributions will contribute to a significantly better understanding of incompatible element behavior, which in turn will allow more accurate geochemical models for whole-rocks system to be developed. A database of accessory mineral distribution coefficients and concentrations will also be made available.

问题：不相容的微量元素模式（例如REE）通常用于模拟高温地质系统中的过程。然而，副矿物，如可能控制不相容的微量元素分布。因此，了解微量元素和辅助矿物的地球化学之间的联系是至关重要的，当地球化学建模地质过程。目的：了解高温地质系统中副矿物对全岩模式的地球化学影响。这将开始侧重于初步检查地壳熔体的形成和各种辅助矿物和不相容的微量元素之间的不同组成的母岩和所产生的熔体的分布。还将研究大型岩浆侵入体中不相容元素的地球化学演化，以提供一个辅助矿物成分数据库，补充和扩大目前只存在锆石和磷灰石的微量元素数据库。这将允许更好地比较本研究的结果与已建立的模型的辅助矿物地球化学和不相容的微量元素的行为在岩浆和高温变质系统。方法学：拟议的研究将开发和应用微分析技术，以满足拟议的研究目标，使用现有的和新开发的ICP-MS技术，围绕在魁北克大学的一个新的设施。在魁北克省的Cap à莱格尔和St. Fulgence，已经确定了最佳的实地研究区域，并将提供对各种母岩和熔体类型的访问。重要性：将微量元素地球化学记录与副矿物分布联系起来，将有助于更好地理解不相容元素的行为，从而可以建立更准确的全岩系统地球化学模型。还将提供一个关于副矿物分布系数和浓度的数据库。