Geochronology of Seafloor Hydrothermal Systems

我的研究计划的总体目标是了解海底块状硫化物(SMS)矿床的资源潜力，开发这些矿床的测年方法，并开发定位和圈定这些沉积物的勘探技术。为了充分了解海底发生的过程，如沉积速率、生境变化、火山作用和矿床形成，有必要确定这些过程发生的时间和速率。使用U系列放射性同位素进行同位素测年是测定海洋环境中年轻(50万年)地质和生物样品的有效工具。拟议研究方案的主要重点是开发测年技术并培训HQP应用这些技术，以更好地了解海底的地质和生物过程，特别是但不限于热液系统和海底块状硫化物矿床的形成和演化。这项研究很重要，因为这些矿床保存了一段时间以来热液喷发的空间、时间和地球化学记录，由于贵重贱金属和贵金属的高度集中，越来越多地被视为潜在的采矿目标。将开发的测年技术同样可以应用于沉积物岩心、玄武岩和深海动物(如珊瑚)，无论是与热液系统有关的还是与其他海洋过程有关的。申请人实验室目前有能力使用伽马能谱技术对相对年轻的富含重晶石的热液样品进行伽马能谱测定，重点是古老的、不活动的海底块状硫化物矿床的组成、保存和勘探。然而，随着我们发现旧的、离轴的矿藏的能力增强，对较老的矿藏进行年代测定的需求也在增加。同样，随着与气候变暖相关的快速环境变化，也需要开发出对低于500年的样品进行测年的技术。拟议的计划将建立在使用质谱分析和伽马光谱分析相结合的样品日期能力的基础上。这一能力的提高将建立一个U系列地质年代学的主要中心，并有能力测定来自热液矿床的地质和生物样品的年代，时间跨度长达500,000年。这项研究的结果将有助于更好地了解海底发生的自然过程。这将与新兴深海采矿业的利益攸关方特别相关，包括商业公司、政府监管机构和非政府组织。这项研究还将有助于我们了解气候变化和人类活动(如渔业、近海石油生产)对海洋环境的影响。

The overarching goal of my research program is to develop an understanding of the resource potential of seafloor massive sulfide (SMS) deposits, develop methods for dating these deposits, and develop exploration techniques for locating and delineating these deposits.In order to fully understand processes that occur on the seafloor, such as sedimentation rates, shifting habitats, volcanism and formation of ore deposits, it is necessary to determine the timing and rates at which these processes occur. Isotope dating using U-series radioisotopes is an effective tool for dating young (<0.5 million years) geological and biological samples in the marine environment. The primary focus of the proposed research program is to develop dating techniques and train HQP in the application of these techniques to better understand geological and biological processes on the seafloor, especially, but not limited to, hydrothermal systems and the formation and evolution of seafloor massive sulfide deposits. This research is important because these deposits preserve a spatial, temporal and geochemical record of hydrothermal venting over time and are increasingly seen as potential mining targets, due to the high concentrations of valuable base and precious metals. The dating techniques to be developed can equally be applied to sediment cores, basaltic rocks and deep-sea fauna (e.g., corals), either in relation to hydrothermal systems or related to other marine processes.Capacity in the applicant's lab currently exists to date relatively young barite-rich hydrothermal samples between ~500 and 16,000 years using gamma spectrometry techniques and is focused on the composition, preservation and exploration of old, inactive seafloor massive sulfide deposits. However, as our ability to find old, off-axis deposits increases, so to does the need to date older deposits. Likewise, with rapid environmental change associated with climatic warming, developing techniques for dating samples younger than 500 years is also required. The proposed program will build on the capacity to date samples using a combination of mass spectrometry and gamma spectrometry. This increased capacity will create a major centre for U-series geochronology, and the capability to date both geological and biological samples from hydrothermal deposits over a full age spectrum up to 500,000 years. The outcomes of this research will lead to a better understanding of the natural processes that occur on the seafloor. This will be particularly relevant for stakeholders in the emerging deep-sea mining industry, including commercial companies, government regulators and NGOs. This research will also help our understanding of the effects of climate change and human activities (e.g., fisheries, offshore petroleum production) on the marine environment.