Ore Precipitation in Epithermal Systems

建议进行现场和实验室研究， 波希米亚区Champion矿浅成低温热液矿床 西喀斯喀特山脉，俄勒冈州。 这份存款记录的脉络 多期的流体流动和沉淀。 领域 一位博士生绘制了一幅关系图， 项目 将对其进行详细研究（流体包裹体 矿石、脉石和蚀变的测量、微探针分析 岩浆岩和成矿作用的Ar-Ar年代学 episodes）。 观察数据将根据以下方面进行解释： 矿石形成的理论模型包括冷却，沸腾， 成矿卤水的氧化还原历史。 数值 模拟将用于模拟（a）硫化物的机制， 金沉淀，和（B）热传递的作用，从 墙岩。 这些研究将有助于理解 许多低温热液矿床。

A combined field and laboratory study is proposed for epithermal ore deposits of the Champion Mine, Bohemia district, in the western Cascades, Oregon. Veins in this deposit record multiple episodes of fluid flow and precipitation. Field relations have been mapped by a PhD student involved in the project. They will be studied in detail (fluid inclusion measurements, microprobe analysis of ore, gangue, and alteration minerals, and Ar-Ar geochronology of igneous and mineralization episodes). Observational data will be interpreted in terms of theoretical models of ore formation involving cooling, boiling, mixing, and redox histories of ore forming brines. Numerical simulations will be used to model (a) mechanisms of sulfide and gold precipitation, and (b) the role of heat transfer to and from wall rocks. These studies will be of application to understanding many epithermal ore deposits.