Crustal fluids and ore genesis

虽然我们在了解地壳流体在矿床形成中的作用方面取得了实质性进展，但由于缺乏金属溶解度和形态的数据，它们的定量建模受到限制。我研究的主要目的是帮助收集这些数据，并利用它们来开发选择矿床类型的遗传模型。我将主要关注HFSE、Au-Ag和Co.这类研究的一个基本假设是矿石流体为液态水。然而，有证据表明，水蒸汽和碳氢化合物也可能在金属运输中起作用。因此，我研究的另一个目标将是评估这种可能性。我的总体方法将是对自然系统和实验系统进行互补研究。将在摩洛哥的Imiter银汞矿床进行研究，以确定为什么它的汞浓度是同类矿床中最高的，而没有金；将在危地马拉的Banderas浅成热液金矿进行研究，以评估新发现的含铵蚀变矿物的意义；将在摩洛哥的Bou Azzer进行研究，以建立热液Co矿床的成因模型；还将在Flin Flon带进行研究，以了解变质作用如何影响中温金矿床，并在印度尼西亚的Merapi火山进行研究，以评估蒸汽介导的金属输运的有效性。将继续在Gallinas Mountains和Strange Lake以及Cirotan的Au-Sn-W进行HFSE矿床的研究。这些实地研究将辅以正在进行的高温金属形态实验和溶解度实验，以确定H2O-H2S-HCl气体的金属运输能力。最后，将进行实验以确定Au和Pd在原油中的溶解度，以便可能应用于Carlin型矿床，Witwatersrand和Kupferschiefer。拟议的研究有可能显著推进对金属矿床形成方式的理解，并有助于指导这些矿床的勘探。它还可以在冶金、解决大气和地下水污染问题方面得到重要应用。

Although we have made substantial progress in understanding the role of crustal fluids in forming ore deposits, their quantitative modeling has been limited by a lack of data on metal solubility and speciation. The main objective of my research is to help gather some of these data, and use them to develop genetic models for a selection of deposit types. I will focus mainly on the HFSE, Au-Ag, and Co. A basic assumption in such studies is that the ore fluid is liquid water. However, there is evidence that aqueous vapour and hydrocarbons may also play a role in metal transport. Thus, another objective of my research will be to evaluate this possibility. My overall approach will be to carry out complementary studies of natural and experimental systems. Studies will be conducted at the Imiter Ag-Hg deposit, Morocco, to determine why it has the highest Hg concentration of any deposit of its type and no Au, the Banderas epithermal Au deposit, Guatemala, to evaluate the significance of newly discovered ammonium-bearing alteration minerals, Bou Azzer, Morocco, to develop a genetic model for hydrothermal Co deposits, and the Questa deposit, USA, to evaluate vapour transport of Mo. A study will also be conducted in the Flin Flon belt to understand how mesothermal Au deposits are affected by metamorphism, and on Merapi volcano, Indonesia, to evaluate the efficacy of vapour-mediated transport of metals. Studies of HFSE deposits will be continued at Gallinas Mountains and Strange Lake, and Au-Sn-W at Cirotan. These field-based studies will be complemented by ongoing high-temperature metal speciation experiments on aqueous liquids, and solubility experiments to determine the metal transport capabilities of H2O-H2S-HCl gases. Finally, experiments will be conducted to determine the solubility of Au and Pd in crude oil, for possible application to Carlin type deposits, the Witwatersrand and the Kupferschiefer.  The proposed research has the potential to significantly advance understanding of how metallic mineral deposits form, and help guide exploration for these deposits. It could also find important applications in metallurgy, and in addressing problems of atmospheric and groundwater pollution.