Geodynamic controls on hydrothermal ore formation in modern subduction zones

现代俯冲带热液成矿的地球动力学控制

• 批准号: RGPIN-2019-04366
• 负责人: Anderson, Melissa
• 金额: $ 1.82万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=751219
• 关键词: Geodynamic; controls; hydrothermal; ore; formation

Increasing demand for base and precious metals has encouraged the search for alternative resources, including mining of hydrothermal vents in the deep sea, known as seafloor massive sulphide (SMS) deposits. Since the discovery of the first vent in 1977, more than 340 active vent sites have been found diverse tectonic settings. Despite 41 years of research, scholars in this field have not adequately constrained the fundamental geologic processes that control where these deposits form, particularly in subduction zones. Seafloor mining may become a reality within the next decade; however, active vent sites host unique chemosynthetic ecosystems that should be protected. There is an urgent need to develop the tools to find inactive vent sites that cannot be detected using traditional techniques. The proposed research program will test the hypothesis that the formation of SMS deposits is directly linked to geodynamic processes on the ocean floor, and that this knowledge can be used to guide regional exploration for inactive deposits. In the next five years, we will focus on developing a robust understanding of the tectonic and volcanic controls on the size, distribution, and composition of newly-discovered active deposits in volcanic arcs, backarc rifts, and oceanic spreading centers. With this information, we will develop regional exploration criteria for inactive deposits that will form the basis of future shiptime proposals to test and refine our models. This program will focus on three subduction zones that represent a variety of structural and volcanic styles: Tonga-Kermadec, Vanuatu and Cascadia. Given the scale of this problem, we will adopt an integrated geological, geochemical and geophysical approach, taking advantage of established partnerships and participation in upcoming research cruises. On land, geological maps are essential for mineral exploration. We will develop new methods for remote-predictive geological mapping of the seafloor using innovative Machine-Learning Algorithms to improve the speed and repeatability of mapping, and We will also adapt land-based approaches to mineral potential mapping for exploration on the seafloor. Together with deposit-scale studies, this work will increase our understanding of geological processes in relatively unexplored areas and will enable more efficient exploration for new deposits on the seafloor. This knowledge will benefit Canadian seafloor mining companies, government regulators, and NGOs, and may inform the creation of Marine Protected Areas in W. Canada. This research also has important implications for exploration for ancient land-based deposits in the long-term. There is an urgent need to train skilled geoscientists who will face the challenge of supplying mineral resources to a growing global population. This program will train HQP in the application of field, laboratory, and remote sensing techniques that will provide them with the knowledge and skills necessary to meet this challenge.

对贱金属和贵金属的需求不断增加，促使人们寻找替代资源，包括开采深海热液喷口，即海底块状硫化物矿床。自1977年发现第一个热液喷口以来，在不同的构造背景下已发现340多个活动热液喷口。尽管经过41年的研究，该领域的学者还没有充分限制控制这些矿床形成的基本地质过程，特别是在俯冲带。海底采矿可能在未来十年内成为现实;然而，活跃喷口所在地拥有独特的化学合成生态系统，应予以保护。迫切需要开发工具，以找到传统技术无法探测到的非活动喷口地点。拟议的研究方案将检验这样一种假设，即SMS矿床的形成与洋底的地球动力学过程直接相关，而且这一知识可用于指导对非活性矿床的区域勘探。在接下来的五年里，我们将专注于发展对火山弧，弧后裂谷和海洋扩张中心新发现的活动矿床的大小，分布和组成的构造和火山控制的强大理解。有了这些信息，我们将为非活跃矿床制定区域勘探标准，这些标准将成为未来测试和完善我们模型的船期建议的基础。该计划将重点关注代表各种结构和火山样式的三个俯冲带：汤加-Kermadec，瓦努阿图和卡斯卡迪亚。鉴于这一问题的规模，我们将采取综合地质、地球化学和地球物理方法，利用已建立的伙伴关系和参与即将进行的研究航行。在陆地上，地质图对矿产勘探至关重要。我们将使用创新的机器学习算法开发海底远程预测地质测绘的新方法，以提高测绘的速度和可重复性，我们还将采用陆基方法进行海底勘探的矿产潜力测绘。这项工作与矿床规模研究一起，将增加我们对相对未勘探地区地质过程的了解，并将使我们能够更有效地勘探海底新矿床。这些知识将使加拿大海底采矿公司、政府监管机构和非政府组织受益，并可能为在西太平洋建立海洋保护区提供信息。加拿大这一研究对古陆矿床的长期勘探也有重要意义。 迫切需要培训熟练的地球科学家，他们将面临向不断增长的全球人口提供矿产资源的挑战。该计划将培训HQP在现场，实验室和遥感技术的应用，这将为他们提供必要的知识和技能，以满足这一挑战。