Experimental determination of phase relations in the system KMASH at pressures between 8 and 11 GPa for a better understanding of deeply subducted or delaminated crustal rocks

合成实验应用于确定K2O-MgO-Al_2O_3-SiO_2-H_2O化学体系的相关系，这是一种描述泥质或酸性岩石的简单体系，压力在8至11 Gpa之间，温度在800°C至1250°C之间，使用步行式多面顶压机。实验将在少量水存在的情况下进行。特别是在这个PT区，以前的热化学计算表明，相关系发生了严重变化，导致这些岩石的密度发生了强烈变化。因此，地壳岩石预计将达到300公里或更深。所有实验还可用于重新计算热力学数据库，其中包括在这些条件下存在的相，这将允许更好地预测在这些超高压条件下的相关系、岩石密度的变化和地壳岩石的脱水行为。

Synthesis experiments should serve for the determination of phase relations in the chemical system K2O-MgO-Al2O3-SiO2-H2O, the simple system describing pelitic or acidic rocks, at pressures between 8 and 11 GPa and temperatures ranging from 800° up to 1250°C using a walker-type multi-anvil press. The experiments would be conducted in the presence of a small amount of water. Especially in this PT-region previous thermochemical calculations suggest severe changes in the phase relations leading to strong changes in the density of those rocks. Thus, crustal rocks are expected to reach depths of 300 km or more. All experiments may serve also for a recalculation of a thermodynamic data base including phases present at these conditions, which will allow a better prediction of the phase relations, the changes in rocks-density and dehydration behavior of crustal rocks at these ultra-high-pressure conditions.