Silicate Melt Density: Effect of Al3+, Fe3+ and Ti4+ Coordination Change

本研究旨在阐明硅酸盐熔体中Al3+、Fe3+和Ti4+的密度与配位变化的关系。实验的目的是在压力为一巴的情况下，使用双波阿基米德方法在一系列成分和温度下获得熔体密度的精确测量。提出的密度测量将补充由核磁共振、拉曼和红外光谱获得的熔体结构信息。密度等性质及其影响因素是研究岩浆演化的基础——它们影响源区的熔体分离，岩浆通过底辟和裂缝上升，以及岩浆中产生化学多样化的过程。

The proposed research will elucidate the relationship between density and coordination changes of Al3+, Fe3+ and Ti4+ in silicate melts. Experiments are designed to obtain precise measurements of melt density using the double-bob Archimedean method over a range of compositions and temperatures at a pressure of one bar. The proposed density measurements will complement information on melt structure obtained by NMR, Raman and IR spectroscopy. Properties such as density, and the factors that affect them, are fundamental in studies of magma evolution - - they affect melt segregration at the source region, magma ascent through diapirs and fractures, and the processes that produce chemical diversification in magmas.