Physical and chemical characterization of zoned minerals as a measure of environmental change

在许多环境中，矿物的分带以不同的长度尺度发生，因为矿物需要时间来生长，这种分带记录了环境随着时间的变化。分带模式可解释为(I)受外力驱动，具有化学不平衡的证据，或(Ii)具有微米级振荡分带的自组织，这里的微量元素对环境变化特别敏感。这项研究将利用近地表环境中的分区矿物化学来量化环境变化的速度和程度。耳石，即硬骨鱼的耳骨，将被用作一种工具，用于i)监测尾矿对水生生物和环境的影响，以及ii)评估鱼类的迁徙行为；以及检查冰中矿物生长的物理和化学控制。生物矿物中的递增结构可以用来建立水环境中的背景化学/微量元素水平，并监测环境变化。生物矿物质对外界驱动的环境变化的反应规模和速度在很大程度上是未知的，生物矿物质经常被有机体的新陈代谢“缓冲”。微量元素的代谢转化使其作为污染物吸收的时间标记物的使用微乎其微。耳石的优势是它们在新陈代谢方面是惰性的，保留了几年到几十年的化学暴露的完整记录。计划在四个领域开展研究：1)耳石的微观化学，重点是耳石中的锶、钡、锰、汞和硒；2)对迁徙鱼类的耳石进行稳定同位素分析，以评估与有机碳(食物来源)有关的微量元素吸收程度；3)合成碳酸钙的微量元素分析；4)海冰碳酸盐矿物的微量元素特征。将用FS-NIR-LA-ICPMS和SIMS分析分带模式。采矿作业需要水来加工和/或储存尾矿，因此资源开采和保护往往被视为相互竞争的利益。随着矿产勘探和全球变暖的进行，这项研究的数据将为土地使用决策和渔业管理实践提供信息，这对加拿大北部的规划至关重要。

Zoning in minerals occurs on a variety of length-scales in many environments, as minerals take time to grow, this zoning records changes in the environment over time. Zoning patterns may be interpreted as (i) driven by external forcing, with evidence of chemical disequilibrium or (ii) self-organization with micron-scale oscillatory zoning, here trace elements are particularly sensitive to environmental change. This research will quantify rates and extent of environmental change using zoned mineral chemistry in near surface environments. Otoliths, ear bones of bony fish, will be used as a tool for i) monitoring the affects of mine tailings on aquatic organisms and environments, and ii) assessing migratory behaviour in fish; and an examination of the physical and chemical controls of mineral growth in ice. Incremental structures in biominerals can be used to establish background chemical/trace element levels in aqueous environments, and monitor environmental change. The scale and rate of response of the biomineral to externally driven environmental change is largely unknown, and the biomineral is often "buffered" by the metabolism of the organism. Metabolic transformation of trace elements makes their use as temporal markers of contaminant uptake tenuous. The advantage of otoliths is that they are metabolically inert, retaining a complete record of chemical exposure over several years to decades. Research is planned in four areas: 1) otolith microchemistry focusing on Sr, Ba and Mn, Hg & Se in otoliths; 2) stable isotope analysis of otoliths from migratory fish species to assess the extent of trace element uptake connected with organic carbon (food sources; 3) trace element analysis of synthetic CaCO3 and 4) trace element characterization of carbonate minerals from sea ice. Zoning patterns will be analyzed by fs-NIR-LA-ICP-MS and SIMS. Mining operations require water for processing and/or tailings storage so resource extraction and conservation are often seen as competing interests. Data from this research will inform land use decisions and fish management practices crucial to planning in northern Canada as mineral exploration and global warming proceed.