Hydrous Components in Nominally Anhydrous Minerals

9804871罗斯曼许多名义上无水的矿物实际上含有低浓度的水或氢氧化物，它们结合在其结构的不同部位。 这些成分对主相性质的影响程度与其实际浓度远远不成比例，并共同构成了地球上全球重要的氢储存库。 我们的研究计划旨在1）表征天然矿物和相关合成材料中这些组分的化学形式和浓度，2）将含水组分与宿主相的其他物理和化学性质联系起来，以及3）探索含水组分对陆地地质系统的意义。我们选择天然存在的矿物从各种地质事件和表征其含水成分与红外光谱。 我们的样品的一个子集，然后将准备用于核剖面分析，可以确定绝对氢含量。将为地壳和地幔中发现的主要矿物组绘制工作曲线。 在受控的温度和压力条件下生长的具有已知化学成分的合成矿物将为检验化学成分对含水成分的影响提供标准。 它们还将处理将从天然矿物获得的信息与其形成条件联系起来的目标。

9804871RossmanMany minerals which are nominally anhydrous actually contain low concentrations of water or hydroxide bound in distinct sites in their structure. These components influence the properties of the host phase toan extent that is far disproportionate to their actual concentrations, and together, constitute a globally significant reservoir of hydrogen in planet Earth. Our research program is directed at 1) characterizing the chemical form and concentrations of these components in natural minerals and related synthetic materials, 2) relating the hydrous components to other physical and chemical properties of the host phases, and 3) exploring the significance of the hydrous components to the terrestrial geologic system. We select naturally occurring minerals from a variety of geologic occurrences and characterize their hydrous components with infrared spectroscopy. A subset of our samples will then be prepared for Nuclear Profile Analysis which can determine the absolute hydrogen content. Working curves will be prepared for major groups of minerals found in both Earths crust and mantle. Synthetic minerals grown under controlled temperature and pressureconditions and with known chemical components will provide standards for examining the influence of chemical composition upon the hydrous components. They also will address the objective of relating information obtained from natural minerals to their conditions of formation.