U.S.-Australia Cooperative Research: Fluids in Amphibolite-to Granulite-Facies Lode Gold Deposits

美国-澳大利亚合作研究：角闪岩至麻粒岩相矿脉金矿中的流体

• 批准号: 9015198
• 负责人: Philip Brown
• 金额: $ 1.29万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-15 至 1992-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9015198&HistoricalAwards=false
• 关键词: U.S.; Australia; Cooperative; Research; Fluids

This award will support collaborative research between Dr. Philip E. Brown of the University of Wisconsin-Madison and Dr. David Groves of the Key Centre for Strategic Mineral Deposits of the University of Western Australia. Most available data on the nature and genesis of Archean lode gold mineralization has been gathered on mesothermal deposits. Fluid compositions and the timing of mineralization are reasonably well agreed upon. There is however considerable continuing debate as to the source of the ore components and the fluid. The objective of this collaborative project is to conduct a fluid inclusion study of lode gold deposits of the Yilgarn Craton in western Australia. The area to be studied contains gold deposits hosted in amphibolite-to granulite- facies metavolcanic and metasedimentary rocks. This research will compare these results which are representative of lower crustal levels and therefore less modified, more proximal, ore fluids to data from the better-studied mesothermal deposits. Extending the range of deposits studied through this project will allow the development of genetic models and general understanding of the mechanisms of gold mineralization, and their relationships to late-Archean tectonics. The project represents excellent U.S. and Australian collaboration. Dr. Brown has many years of experience in fluid-inclusion studies involving ore deposits and/or metamorphic terranes and the background in theoretical fluid modeling that will be necessary to interpret the pressure- temperature-composition history of the fluids trapped in inclusions in high-grade metamorphic rocks. The Australian research group has an excellent international reputation, and the documentation of mineralization in the Yilgarn Craton required for the study. In addition to providing useful data on the fluid characteristics and conditions of mineralization, the research has the potential for broader application in interpretation of gold deposition world-wide in Archean terranes and in exploration models for similar gold deposits.

该奖项将支持威斯康星大学麦迪逊分校的菲利普·E·布朗博士和西澳大利亚大学战略矿产关键中心的大卫·格罗夫斯博士之间的合作研究。有关太古宙脉金矿化性质和成因的现有资料大多收集在中热液型矿床上。流体成分和成矿时间相当一致。然而，关于矿石成分和流体的来源，仍有相当大的持续争论。该合作项目的目标是对西澳大利亚伊尔加恩克拉通的矿脉金矿进行流体包裹体研究。研究区金矿床赋存于角闪岩-麻粒岩相变火山岩和变质沉积岩中。这项研究将把这些代表较低地壳水平的结果与研究较好的中温热液矿床的数据进行比较，这些结果代表了较低的地壳水平，因此较少修改，更接近于矿石流体。通过这一项目扩大所研究的矿床范围，将有助于发展成因模型和对金矿化机制及其与晚太古宙构造的关系的总体了解。该项目代表了美国和澳大利亚的良好合作。布朗博士在涉及矿床和/或变质地体的流体包裹体研究方面拥有多年经验，并拥有理论流体建模的背景，这将是解释高级变质岩中包裹体中流体的压力-温度-成分历史所必需的。澳大利亚研究小组在国际上享有盛誉，研究所需的伊尔加恩克拉通的矿化文件。除了提供有关流体特征和成矿条件的有用数据外，这项研究还有可能在解释世界范围内太古代地体中的金矿沉积以及类似金矿的勘探模式中得到更广泛的应用。