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.

CarmichaelEAR-0125159 虽然表示水在岩浆中的溶解度与 P、T 和液体成分的函数关系的简单表达式对于许多水相平衡实验来说是足够的，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压力容器，建议测量两种哥伦比亚河玄武岩中的水溶性作为 P & T 的函数，以确保溶解度算法的成分外推到不同二氧化硅浓度的富铁液体。已发表的对岩浆中溶解水体积的直接测量结果将包含在修订后的算法中（早期公式中的回归变量），以确保溶解度关系的压力依赖性可以外推到已发表的高压实验。与角闪石相关的中间熔岩发生俯冲作用的物质总是比它们的无角闪石的伙伴氧化得更多。其原因尚不清楚，可能是由于喷发时溶解的水与硫物质结合而被排出而间接造成的。这将通过使用新开发的 X 射线荧光技术来测量大量地下结晶熔岩中的硫浓度进行测试，这些熔岩的氧化还原状态是​​众所周知的。