Collaborative Research: Experimental Determination of the Damp Peridolite Solidus

合作研究：潮湿橄榄岩固相线的实验测定

• 批准号: 1459649
• 负责人: Glenn Gaetani
• 金额: $ 42.35万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1459649&HistoricalAwards=false
• 关键词: Collaborative; Research; Experimental; Determination; Damp

The development and application of new experimental approaches that can control key components of a system provide opportunities for breakthroughs; not only for the topic for which the method was developed, but many times also for other systems and disciplines. This research takes a novel, newly developed approach for quantitatively controlling very small amounts of H2O in high temperature/pressure experiments and applies it to one of the most fundamental rock forming processes on the planet: the melting of mantle rocks (peridotite) to form magmas, some of which eventually reach Earth?s surface. Because hydrogen diffuses rapidly into olivine, one of the most common minerals in the Earth?s mantle, the researchers receiving this award are now able to infuse predetermined concentrations of H2O into spheres of olivine about 300 microns in diameter. These olivines are then used as hygrometers in experiments that allow the pressure dependence to be determined of the exact instant when melting of mantle rock begins (i.e., the peridotite solidus). Understanding this fundamental reaction is important because the melting of Earth's mantle (i.e., peridotite) drives the spreading apart of the mid-ocean ridges and has a significant impact on the transfer of mass and heat from Earth?s interior to its surface as well as on the thickness of Earth?s crust.To determine the lherzolite solidus at H2O-undersaturated conditions, partial melting experiments around 1300 C and from 1 to 3 GPa will be conducted using synthetic peridotite containing spheres of San Carlos olivine doped with specified H2O contents. Using the spheres as hygrometers, the olivines will be analyzed by secondary ion mass spectrometry to determine when the H2O content of the olivine changes, indicating the initiating of melting. Research goals are to determine the peridotite solidus and the impact of Na2O and mineral mode on melting. Results will provide the first quantitative experimental determination of the H2O-undersaturated peridotite solidus. Broader impacts of the work include method development and application, thus, building infrastructure for science. It also provides student training at the graduate and undergraduate level. The unique mineralogical hygrometer may also have applications for materials science and other areas where the exact temperature and pressure of a solidus for a material of a specific composition is needed.

可以控制系统关键组成部分的新实验方法的开发和应用为突破提供了机会；不仅是为了开发该方法的主题，而且对于其他系统和学科的主题也很多次。 这项研究采用了一种新颖的，新开发的方法，用于在高温/压力实验中定量控制非常少量的H2O，并将其应用于地球上最基本的岩石形成过程之一：地幔岩石（Peridotite）的融化以形成岩浆，其中一些最终到达地球表面。由于氢迅速扩散成橄榄石，这是地球上最常见的矿物之一，因此获得该奖项的研究人员现在能够将H2O的预定浓度注入到橄榄石球体中，约300微米。然后，这些橄榄石在实验中用作湿度计，从而使压力依赖性确定在地幔岩石开始时的确切瞬间（即橄榄岩固体）。 Understanding this fundamental reaction is important because the melting of Earth's mantle (i.e., peridotite) drives the spreading apart of the mid-ocean ridges and has a significant impact on the transfer of mass and heat from Earth?s interior to its surface as well as on the thickness of Earth?s crust.To determine the lherzolite solidus at H2O-undersaturated conditions, partial melting experiments around 1300 C and from 1 to 3 GPa will使用含有指定的H2O含量的San Carlos橄榄石球的合成橄榄岩进行进行。 将球体用作湿度计，将通过二级离子质谱法分析橄榄石，以确定橄榄石的H2O含量何时变化，表明熔化的启动。研究目标是确定橄榄岩固体以及Na2O和矿物模式对熔化的影响。结果将提供第一个定量的实验确定，对H2O饱和橄榄岩固体固体。这项工作的更广泛的影响包括方法开发和应用，因此，为科学构建基础设施。它还在研究生和本科阶段提供学生培训。独特的矿物学湿度计也可能针对材料科学和其他领域的应用，在这些区域中，需要在特定成分的材料中确切的温度​​和压力。