Experimental Study of Silver in High-Temperature Magmatic-Hydrothermal Systems

烛台岩浆热液矿床，如许多斑岩、夕卡岩及其相关矿床，以及许多浅成热液矿床，在空间和时间上都与中英质侵入火成岩有关。我们建议通过研究银在共存熔体、结晶硫化物、金属和氧化物相之间的分配，为岩浆-热液系统中银的物理化学建立初步的基线。这些数据将允许估计高温斑岩型流体中Ag:Au:Cu的模型活度比。此外，这些数据可以用来估计热液流体中Cu-Fe硫化物的结晶如何改变流体中Ag与Au的比例，以及岩浆硫化物或氧化物相的结晶或破坏如何改变高等级岩浆的银含量。这将允许对假设进行更多的定量测试，例如，进入浅成热液环境的含盐岩浆流体脉冲可以提供大量的银，或者斑岩型矿石的金银预算是由银和金的温度依赖性分配成Cu-Fe硫化物控制的。将挥发相捕获在石英流体包裹体中，并用LA-ICPMS进行分析。这些数据将作为构建金银矿床勘探模型的基础。此外，我们的团队有一个记录，包括高中生、本科生、硕士和博士生参与我们的研究。我们所有的研究生都参与了本科教学。此外，我们积极参与各种形式的外展活动(例如，由GSA赞助的教育合作伙伴计划（PEP）；为国家公园管理局在约塞米蒂国家公园的护林员翻译项目提供培训；以及参观小学)。

EAR-0309967CandelaMagmatic-hydrothermal ores, such as many porphyry, skarn and related ores, as well as many epithermal deposits, are related spatially and temporally to intermediate to felsic intrusive igneous rocks. We propose to establish a preliminary baseline for the physical chemistry of silver in magmatic-hydrothermal systems by examining the partitioning of silver among coexisting melts, crystalline sulfide, metal and oxides phases. These data will allow the estimation of a model activity ratio of Ag:Au:Cu in high-temperature porphyry type fluids. Additionally, these data can be used to estimate how the crystallization of Cu-Fe sulfides from a hydrothermal fluid changes the ratio of Ag to Au in the fluid, and how the crystallization or destruction of magmatic sulfide or oxide phases might modify the silver content of high-level magmas. This will allow more quantitative testing of hypotheses such as the suggestion that pulses of saline magmatic fluids into the epithermal environment can supply significant quantities of silver, or that the gold and silver budgets of porphyry type ores is controlled by the temperature dependent partitioning of Ag and Au into Cu-Fe sulfides. Volatile phases will be trapped in quartz fluid inclusions and analyzed by LA-ICPMS. These data will serve as a basis for the construction of exploration models for both gold and silver deposits. Further, our group has a track record involving a mix of high school, undergraduate, masters and doctoral students in our research. All of our graduate students are involved in undergraduate teaching. Furthermore, we actively participate in outreach in a variety of formats (e.g. Partners in Education Program (PEP) sponsored by GSA; training for the Ranger Interpreter Program in Yosemite National Park for the National Park Service; and visits to elementary schools).