CAREER: Partitioning of Rare Earth Elements (REE) Between Minerals and Aqueous Fluids in Ore Deposits

GSTDTAP

项目编号	1845258
	CAREER: Partitioning of Rare Earth Elements (REE) Between Minerals and Aqueous Fluids in Ore Deposits
	Alexander Gysi (Principal Investigator)
主持机构	Colorado School of Mines
项目开始年	2019
	2019-07-01
项目结束日期	2024-06-30
资助机构	US-NSF
项目类别	Continuing grant
项目经费	102521(USD)
国家	美国
语种	英语
英文摘要	The rare earth elements (REE) have similar but slightly different ionic radii and atomic masses, which permits studying the fundamental behavior of chemical elements and their incorporation in mineral structures in natural systems. Their magnetic properties make them important components in permanent magnets used in wind turbines, batteries of hybrid cars, and phosphors in energy efficient light. The REE composition of minerals is also used in geosciences to trace geological processes in the Earth's crust. Ore deposits commonly form at depth through the mobilization of metals in aqueous fluids and the mineralization in hydrothermal veins. The properties of both, the fluid and the minerals, will affect how the different REE are fractionated. Currently, we have much to discover about how to quantify systematically the trace element signatures of minerals with regards to fluid-rock interaction and ore-forming processes. This CAREER proposal explores how REE fractionate between aqueous fluids and minerals in ore deposits using laboratory experiments, numerical modeling and fluid inclusions trapped in natural minerals. The THERMO fluids project will be initiated with the preparation of a Fluids & Minerals summer school for undergraduate students, an open access booklet, and a dedicated hands-on thermodynamics tutorial webpage. A major aim of this project will be to provide an education platform and demonstrate the broader significance of thermodynamics in geosciences. Calcite, fluorite and apatite are common gangue minerals associated to REE and other mineral deposits. These minerals record geochemical signatures that may be used to determine temperature, fluid chemistry and potentially fluid pathways associated to ore-forming processes. This research involves a comprehensive series of hydrothermal experiments at 100 to 350 degrees C for determining the partitioning of REE between aqueous fluid-calcite, -apatite and -fluorite as a function of temperature and fluid composition (i.e., salinity, pH and ligand activity). The experimental data will be used to develop a new thermodynamic model for predicting and quantifying REE signatures in these hydrothermal minerals. To test the model, a set of mineral trace element compositions and fluid inclusions will be studied in peralkaline, carbonatite, and iron oxide-apatite hosted ore deposits in North America. The objective of the proposed research is to provide a framework for simulating the partitioning of trace metals associated to fluid-rock reactions in ore deposits and advance our capabilities of modeling and interpreting ore-forming processes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/213054
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Alexander Gysi .CAREER: Partitioning of Rare Earth Elements (REE) Between Minerals and Aqueous Fluids in Ore Deposits.2019.