Nature of Silicate Melts: Role of Highly Charged Cations

这是由美国国家科学基金会资助EAR-8416796的研究的延续，该研究旨在确定高电荷阳离子在过碱性、铝质和过铝质“花岗岩”熔体中的溶解行为。本文拟进行的研究包括：(1)在掺杂TiO2、P2O5、1A族和2A族元素的K2O-Al2O3-SiO2熔体中测定Fe+2 -Fe+3的氧化还原平衡；(2)利用穆斯堡尔光谱测定这些熔体中Fe+3的配位；(3)金红石、锡石等单一氧化物相的饱和度作为第1族元素和第2族元素P2O5的函数；TiO2和B2O3含量，(4)过碱性熔体中一氧化相饱和度随H2O含量的变化，(5)振动和核磁共振光谱K2O。含5周期元素的5SiO2玻璃；(6)在含氟和含氯熔体中进行了两次液体分配实验。这些研究结合平衡的热力学模型将增加我们对这些重要端元类型花岗岩岩浆中发生的复杂相互作用的理解。

This is a continuation of the research supported by NSF grant EAR-8416796 to determine the solution behavior of highly charged cations in peralkaline, metaluminous and peraluminous "granitic" melts. The proposed research involves the determination of (1) the redox equilibria of Fe+2 -Fe+3 in K2O-Al2O3-SiO2 melts doped with TiO2, P2O5, Group 1A and Group 2A elements, (2) the coordination of Fe+3 in these melts using Mossbauer spectroscopy, (3) the saturation of unary oxide phases such as rutile, cassiterite among others as functions of Group 1 and, Group 2 elements, P2O5, TiO2 and B2O3 contents, (4) the saturation of unary oxide phases as functions of H2O content in peralkaline melts, (5) vibration and NMR spectra K2O.5SiO2 glasses containing Period 5 elements, (6) two liquid partitioning experiments in flourine and chlorine-doped melts. These studies combined with thermodynamic modeling of the equilibria will increase our understanding of the complex interactions that occur in these important end-member types of granitic magmas.