Factors Affecting Base Metal Mobility in Subseafloor Hydrothermal Systems

相对低压和接近超临界温度的盐水在亚>中起着重要作用。b>中期海底交替过程。>海洋山脊。然而，在这些条件下，主要交替矿物，特别是硫化物和铝硅酸盐的溶解度的实验数据明显缺乏。海水低压超临界区（3.2% NaCl）的物理参数（密度、介电常数）随压力的微小变化而发生显著变化。矿物>浓度关系。b>流体平衡及岩石b>理论模型。>流体相互作用。研究了闪锌矿和黄铜矿、斜长石和绿帘石在低压超临界区pH和氧化还原缓冲NaCl流体中的溶解度和反应性。实验结果将(1)允许用更复杂的模型来预测金属浓度；(2)明确氯离子对流体pH的控制作用；(3)明确了可以测量中期温度和/或压力的矿物的相关系。>海洋山脊。

Salt water at relatively low pressures and near super critical temperatures appears to play a prominent role in sub>.>seafloor alternation process at mid>.>ocean ridges. Experimental data for the solubility of key alternation minerals, especially sulfides and aluminosilicates, however, are conspicuously lacking for these conditions. The low pressure supercritical region of seawater (3.2% NaCl) is characterized by physical parameters (density,dielectric constant) which changes dramatically with slight change in pressure complicating aqueous activity>.>concentration relations, mineral>.>fluid equilibria, and theoretical models of rock>.>fluid interaction. Experiments are designed to assess the solubility and reactivity of sphalerite and chalcopyrite, and plagioclase and epidote respectively in pH and redox buffered, NaCl fluids in the low pressure supercritical region. Results of the experiments will (1) allow predictions of metal concentrations to be made from more sophisticated models; (2) define the role of chloride ion controlling fluid pH; and (3) specify phase relationships of minerals that can measure temperature and/or pressure at mid>.>ocean ridges.