Effects of Water on Electrical Conductivity in Majorite

矿物的电导率对温度和缺陷化学（如氢相关缺陷的浓度）敏感，但对主要元素化学或压力不太敏感。因此，通过实验室数据对电化学推断的电导率进行比较，将对温度和含水量提供重要的限制。然而，氢相关的缺陷对电导率的作用的实验研究是具有挑战性的，并且很少有数据可用于为此类研究提供基础。为了实现这一目标，PI和他的同事们最近确定了wadsleyite和ringwoodite中电导率和含水量之间的关系。然而，这种关系还没有被实验确定的另一种重要的矿物，镁橄榄石石榴石，因此，水含量和电导率之间的关系在过渡区是不确定的。 在本计画中，将透过高压、高温实验，研究氢相关缺陷对镁合金导电性的影响。研究结果将为推断地球过渡带水（氢）含量和温度提供坚实的基础。

Electrical conductivity of minerals is sensitive to temperature and defect chemistry (such as the concentration of hydrogen-related defects), but less sensitive to major element chemistry or pressure. Consequently, a comparison of geophysically inferred electrical conductivity with laboratory data will provide important constraints on temperature and water content. However, experimental studies on the role of hydrogen-related defects on electrical conductivity are challenging and very few data are available to provide a basis for such studies. To achieve such a goal, the PI and his colleagues have recently determined the relation between electrical conductivity and water content in wadsleyite and ringwoodite. However, such relationship has not been determined experimentally for another important mineral, majorite garnet, and consequently, the relationship between water content and electrical conductivity in the transition zone is uncertain. In this project, an experimental study on the role of hydrogen-related defects in the electrical conductivity in majorite will be conducted through high-pressure, temperature experiments. The results will provide a solid basis for inferring water (hydrogen) content and temperature in Earth's transition zone.