Collaborative Research: Experimental Study of Mineral-Fluid Fractionation of Non-Traditional Isotopes (Fe, Cu, Zn, S) with Implications for Seafloor Hydrothermal Systems

合作研究：非传统同位素（Fe、Cu、Zn、S）的矿物流体分馏实验研究对海底热液系统的影响

• 批准号: 1232704
• 负责人: William Seyfried
• 金额: $ 26.8万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1232704&HistoricalAwards=false
• 关键词: Collaborative; Research; Experimental; Study; Mineral

Many empirical studies of hydrothermal vent systems on the seafloor and an increasing number of biogeochemical studies are being carried out to look at various mineralogical and biological processes using unconventional stable isotopes (i.e., those of heavy elements such as iron, zinc, copper, and sulfur). To allow quantitative and predictive results of these empirical studies, fractionation factors of these isotopes must be known. However, at present, no experimental work to derive these coefficients and parameters have been carried out. This research builds off a one-year proof-of-concept study to show that fractionation occurs in these systems in a systematic way. The new project examines the effects of temperature, fluid chemistry, and reaction rate on the fractionation of non-traditional stable isotopes (Fe, Cu, Zn, S) between sulfide minerals and fluids at elevated temperatures and pressures. The work will include phase separation experiments to assess the role of fluid chemistry on non-traditional stable isotope fractionation between vapor and brine. It will use isotope tracers in equilibrium experiments to look at reaction progress and to see how isotope systematics respond to reaction rates and mechanisms. Sulfur isotope exchange for homogeneous and heterogeneous systems will also be tested experimentally. Broader impacts of the work include building fundamental infrastructure for science via the development of kinetic and fractionation factors that are essential for the development of theoretical models for predicting stabilities of minerals containing Fe, Cu, Zn, and S. Impacts also include the engagement of graduate and undergraduate students in state-of-the-art experimental studies of water-rock interaction and the involvement of an early career PI from an institution in an EPSCOR State (Louisiana).

对海底热液喷口系统的许多实证研究和越来越多的生物地球化学研究正在进行中，以使用非常规稳定同位素（即铁、锌、铜和硫等重元素）来研究各种矿物学和生物过程。 ）。为了获得这些实证研究的定量和预测结果，必须知道这些同位素的分馏因子。 然而，目前尚未开展推导这些系数和参数的实验工作。 这项研究以为期一年的概念验证研究为基础，旨在表明这些系统中会系统地发生分馏。新项目研究了温度、流体化学和反应速率对高温高压下硫化物矿物和流体之间非传统稳定同位素（Fe、Cu、Zn、S）分馏的影响。这项工作将包括相分离实验，以评估流体化学对蒸气和盐水之间的非传统稳定同位素分馏的作用。它将在平衡实验中使用同位素示踪剂来观察反应进程，并了解同位素系统学如何响应反应速率和机制。均质和异质系统的硫同位素交换也将通过实验进行测试。这项工作的更广泛影响包括通过动力学和分馏因子的发展建立科学基础设施，这对于开发预测含铁、铜、锌和硫矿物稳定性的理论模型至关重要。影响还包括研究生的参与和本科生参与最先进的水岩相互作用实验研究，并由 EPSCOR 州（路易斯安那州）一家机构的早期职业 PI 参与。