Numerical Modeling of Reaction-Enhanced Fluid Flow and Isotopic Exchange in Contact Aureoles

接触光环中反应增强流体流动和同位素交换的数值模拟

• 批准号: 0408564
• 负责人: Peter Nabelek
• 金额: $ 16.25万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0408564&HistoricalAwards=false
• 关键词: Numerical; Modeling; Reaction; Enhanced; Fluid

Along with metamorphism, fluid flow is the most important process that occurs in contact aureoles of igneous intrusions. Fluid flow drives metamorphic reactions and induces advective heat and mass transport. There is a very large body of field, chemical, mineralogic, and fluid inclusion data that demonstrate that magmatic-hydrothermal systems are very complex, spatially variable, and compositionally evolve through time as thermal conditions change. However, the temporal evolution of these processes during a contact metamorphic event is often difficult to decipher from petrology and geochemistry. Numerical computer techniques provide means to examine two and three-dimensional aspects of contact aureole evolution with time. The goal of this research is to numerically examine how transient permeability changes that are inherent to rocks in which metamorphic reactions produce volatiles, influence fluid fluxes, compositions of evolving fluids, and chemical exchange between rocks and fluids in magma-driven hydrothermal system. The results will serve as a guide for interpreting mineralogic, trace element and stable isotope signatures of fluid flow in fossil magmatic-hydrothermal systems. In a broader context, this study will enhance our understanding of the long-term behavior of deep, magma-driven hydrothermal systems, including volcanic and geothermal systems, and ore-generating processes. These hydrothermal systems have played a key role in mass redistribution in the Earth's crust and its chemical evolution and are responsible for concentrating metals that can be explored economically. This project will train a graduate student that will be proficient in computational modeling of complex processes. In terms of outreach to the community, an undergraduate student will be hired to help in production of a guide to the software that could be later distributed to interested parties.

除了变质作用之外，流体流动是火成岩侵入体接触光环中发生的最重要的过程。流体流动驱动变质反应并引起平流热量和质量传递。大量的现场、化学、矿物学和流体包裹体数据表明，岩浆-热液系统非常复杂，空间可变，并且随着热条件的变化，成分随着时间的推移而演变。然而，接触变质事件期间这些过程的时间演化通常很难从岩石学和地球化学中解读。数值计算机技术提供了检查接触光环随时间演变的二维和三维方面的方法。本研究的目的是通过数值研究岩石固有的瞬态渗透率变化如何影响岩浆驱动的热液系统中的变质反应产生挥发物、流体通量、演化流体的成分以及岩石和流体之间的化学交换。研究结果将作为解释化石岩浆-热液系统中流体流动的矿物学、微量元素和稳定同位素特征的指南。在更广泛的背景下，这项研究将增强我们对深层岩浆驱动的热液系统（包括火山和地热系统）以及矿石生成过程的长期行为的理解。这些热液系统在地壳的质量重新分布及其化学演化中发挥了关键作用，并负责富集可经济勘探的金属。 该项目将培养一名精通复杂过程计算建模的研究生。 在社区推广方面，将聘请一名本科生帮助制作软件指南，该指南随后可以分发给感兴趣的各方。