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

高温岩浆-热液系统中银的实验研究

• 批准号: 0309967
• 负责人: Philip Candela
• 金额: $ 33万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-06-01 至 2007-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0309967&HistoricalAwards=false
• 关键词: Experimental; Study; Silver; Temperature; Magmatic

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).

Candela岩浆热液矿石，如许多斑岩、矽卡岩和相关矿石，以及许多浅成热液矿床，在空间和时间上与中长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一个初步的基线。 这些数据将允许估计高温斑状流体中Ag：Au：Cu的模型活度比。此外，这些数据可以用来估计如何从热液流体中的铜-铁硫化物的结晶改变流体中的银与Au的比例，以及如何结晶或岩浆硫化物或氧化物相的破坏可能修改高级别岩浆的银含量。这将允许对假设进行更多的定量测试，例如，盐水岩浆流体进入浅成热液环境的脉冲可以提供大量的银，或者斑岩型矿石的金和银预算受Ag和Au向Cu-Fe硫化物中的温度依赖性分配的控制。 挥发相将被捕获在石英流体包裹体中，并通过LA-ICPMS进行分析。这些数据将作为建立金、银矿床勘查模型的基础。 此外，我们的团队在我们的研究中有高中生，本科生，硕士生和博士生的混合记录。 我们所有的研究生都参与本科教学。此外，我们还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）;为国家公园服务处在约塞米蒂国家公园举办的护林员翻译计划培训;以及访问小学）。