Experimental investigation of K and Na partitioning between miscible liquids

Model silicate melts with variable Al₂O₃ and SiO₂ contents were experimentally saturated with alkalis at a total pressure of 1 atm and temperatures of 1300–1470°C, using the crucible supported loop technique. It was shown that Al₂O₃ content has little influence on the degree of silicate melt saturation with K and Na. In contrast, SiO₂ content strongly affects the solubility of alkalis in silicate melts. Model calculations were performed to evaluate the behavior of alkalis during the contamination/mixing of basic and silicic magmas.