Water solubility in phonolite melts: Influence of melt composition and temperature
Water solubility in phonolite melts: Influence of melt composition and temperature
复制标题
响石熔体中的水溶性：熔体成分和温度的影响
DOI：
10.1016/j.chemgeo.2008.06.043
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发表时间：
2008
期刊：
影响因子：
3.9
通讯作者：
H. Behrens
中科院分区：
文献类型：
--
作者：
B. Schmidt;H. Behrens
在压力为50 ~ 395 MPa、温度为850 ~ 1200 °C的条件下，通过实验测定了各种响岩熔体的水溶性。本研究的目的是阐明在何种程度上的化学和物理参数，如相对量的碱金属和碱土金属元素或温度影响的水溶性。为此，共制备了10种不同的响岩玻璃。对于一系列的四种玻璃，Na/（Na+K）比从0.2变化到0.8，对于另一系列的四种玻璃，（Na+K）/（Ca+Mg）比从2.8变化到10.1，同时保持Na/（Na+K）恒定在0.4。对于这两个系列，在1200 °C和50至395 MPa的压力下在内部加热的压力容器中进行水溶性实验。数据表明，这两个化学变量对水溶性的影响相当小。例如，在2千巴和1200 °C下，Na/（Na+K）比从0.2增加到0.8导致水溶解度增加约0.4重量%。(5.58至5.94重量%），而将（Na+K）/（Ca+Mg）比从2.8增加到10.1导致约0.2重量%的增加，水在压力为50、100、150、200、250和300 MPa，温度在850和1200 °C之间的条件下，研究了两种响岩组合物的温度效应，这两种响岩组合物代表了西班牙特内里费岛的Montaña Blanca和德国东艾弗尔的Laacher See火山复合体。在这些条件下，两种熔体均表现出约-0.1至-0.24重量%的负温度依赖性。每100 °C的水。最强的温度依赖性（最负的值）发生在150至200 MPa，似乎接近零略高于300 MPa。
The water solubility in various phonolite melts was determined experimentally at pressures between 50 and 395 MPa and at temperatures between 850 and 1200 °C. The aim of this study was to elucidate to which extent chemical and physical parameters such as relative amounts of alkali and alkaline earth elements or temperature affect the water solubility. For this purpose a total of 10 different phonolite glasses were prepared. For a series of four glasses, the Na/(Na+K) ratio was varied from 0.2 to 0.8, for another series of four glasses, the (Na+K)/(Ca+Mg) ratio was varied from 2.8 to 10.1, while keeping Na/(Na+K) constant at 0.4. For these two series water solubility experiments were performed at 1200 °C and pressures between 50 and 395 MPa in an internally heated pressure vessel. The data show that both chemical variables have rather small effects on the water solubility. For instance, at 2 kbar and 1200 °C an increase in Na/(Na+K) ratio from 0.2 to 0.8 leads to an increase in water solubility of about 0.4 wt.% (5.58 to 5.94 wt.%), while increasing the (Na+K)/(Ca+Mg) ratio from 2.8 to 10.1 leads to an increase of about 0.2 wt.% water. The effect of temperature was investigated for two phonolite compositions, representative of Montaña Blanca, Tenerife, Spain and the Laacher See volcanic complex, East Eifel, Germany at pressures of 50, 100, 150, 200, 250 and 300 MPa, and temperatures between 850 and 1200 °C. At these conditions both melts exhibit negative temperature dependence ranging from about −0.1 to −0.24 wt.% water per 100 °C. The strongest temperature dependence (most negative values) occurs at 150 to 200 MPa and seems to approach zero slightly above 300 MPa.