Age of Formation of Carlin-Type Gold Deposits and Relationship to Tectonic Environments

卡林型金矿床形成时代及其与构造环境的关系

• 批准号: 9805384
• 负责人: Greg Arehart
• 金额: $ 11万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9805384&HistoricalAwards=false
• 关键词: Age; Formation; Carlin; Type; Gold

9805384ArehartCarlin-type gold deposits (CTDs) are a major focus of mining and exploration activity in the US today, yet processes leading to their genesis are poorly understood. The goal of this research is to investigate the causes and conditions of Carlin-type gold deposit formation by addressing questions regarding the timing of deposition and the relationship between hydrothermal circulation, ore deposition, and magmatic and tectonic events. Of particular importance is resolution of the question of whether there is a common theme responsible for CTD formation either through magmatic association or unique tectonic environment. In order to address the fundamental issue of CTD formation age several avenues will be followed at individual deposits in the Carlin Trend: acquisition and synthesis of geological, petrological and structural data; stable isotope comparison of mineralizing fluids with secular curves for meteoric waters; conventional and laser-assisted argon geochronology on igneous rocks and alteration minerals; fission-track dating of apatite and zircon; and U-Pb dating of hydrothermal apatite. In addition, the applicability of the rhenium-osmium system for direct dating of gold-bearing sulfides will be explored. By understanding the timing of ore deposition additional constraints will be placed on the potential sources of fluids and heat to drive hydrothermal circulation in Carlin-type gold deposits.

9805384ArehartCarlin 型金矿 (CTD) 是当今美国采矿和勘探活动的主要焦点，但人们对其成因的过程却知之甚少。本研究的目的是通过解决沉积时间以及热液循环、矿石沉积、岩浆和构造事件之间的关系等问题，调查卡林型金矿床形成的原因和条件。特别重要的是解决CTD形成是否存在一个共同主题的问题，无论是通过岩浆组合还是通过独特的构造环境。为了解决 CTD 形成年龄的基本问题，Carlin Trend 中的各个矿床将采取多种途径：获取和综合地质、岩石学和结构数据；矿化流体与大气水长期曲线的稳定同位素比较；火成岩和蚀变矿物的常规和激光辅助氩地质年代学；磷灰石和锆石的裂变径迹测年；和热液磷灰石的 U-Pb 定年。此外，还将探索铼-锇系统对含金硫化物直接定年的适用性。通过了解矿石沉积的时间，将对驱动卡林型金矿床热液循环的潜在流体和热量来源施加额外的限制。