Hydrous Intermediate Magmas

含水中质岩浆

• 批准号: 0125159
• 负责人: Ian S. Carmichael
• 金额: $ 8.22万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0125159&HistoricalAwards=false
• 关键词: Hydrous; Intermediate; Magmas

CarmichaelEAR-0125159Although the simple expression representing the solubility of water in magmas as a function of P,T and liquid composition, is adequate for many hydrous phase-equilibrium experiments, its extrapolation to iron-rich basalts and to higher pressures is problematic. Using our internally heated pressure vessel, it is proposed to measure the water solubility in two Columbia River basalts as a function of P & T to make secure the compositional extrapolation of the solubility algorithm to Fe-rich liquids of varying silica concentration. Published direct measurements of the volume of dissolved water in magmas will be included in the revised algorithm (a regressed variable in the early formulation) to ensure that the pressure dependence of the solubility relationship extrapolate to published high pressure experiments.Hornblende-bearing intermediate lavas associated with subduction are always more oxidized than their hornblende-free associates. The reasons for this are unknown and could indirectly result from the expulsion of dissolved water on eruption in combination with a sulfur species. This will be tested by using a newly developed X-Ray fluorescence technique to measure the sulfur concentration in a large collection of sub-aerial crystalline lavas for which the redox state is well known.

虽然水在岩浆中的溶解度作为P、T和液体成分的函数的简单表达式对于许多含水相平衡实验是足够的，但将其外推到富铁玄武岩和更高的压力是有问题的。使用我们的内部加热的压力容器，建议测量两个哥伦比亚河玄武岩的水溶解度作为一个函数的P-T，使安全的组成外推的溶解度算法的富铁液体的不同的二氧化硅浓度。公布的直接测量的体积溶解水在岩浆中将被包括在修订后的算法（在早期配方的回归变量），以确保压力依赖的溶解度关系外推到公布的高压experiments.Hornblende-bearing中间熔岩与俯冲总是比他们的Hornblende-free联营公司氧化。其原因尚不清楚，可能是喷发时溶解水与硫物质结合的间接结果。这将通过使用一种新开发的X射线荧光技术来测试，以测量在大量收集的亚气晶熔岩的氧化还原状态是众所周知的硫浓度。