Accomplishment Based Renewal: Magmatic Processes at Mid-Ocean Ridges

基于成就的更新：大洋中脊的岩浆过程

• 批准号: 0524922
• 负责人: John Sinton
• 金额: $ 34.41万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-10-01 至 2009-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0524922&HistoricalAwards=false
• 关键词: Accomplishment; Based; Renewal; Magmatic; Processes

ABSTRACT (0524922) Sinton Intellectual Merit: This project investigates processes that control the chemical composition and mineralogy of mid-ocean ridge volcanic rocks. It specifically addresses how variations in melting of upwelling mantle affect the composition of primary magmas and how these magmas are changed in chemistry and mineralogy by cooling and crystallization at different depths in the crust and mantle. This research combines theoretical models, geophysical constraints on the thickness of the crust, and chemical and petrographic analyses of natural samples from the Galapagos Spreading Center and Icelandic Western Volcanic Zone mid-ocean ridges. These contrasting sample sets will allow evaluation how variations in spreading rate, mantle source composition, mantle temperature, crustal thickness and variations in eruptive style create physical and chemical variations in mid-ocean ridge lavas at specific locations along spreading ridges. The work involves determining the relative proportions of individual minerals (olivine, feldspar, pyroxene and oxide) in selected samples and analyzing for the chemical compositions of these minerals as well as of whole-rock samples. Specific sample sets include: (1) unusual submarine lavas from the Galapagos area with very high aluminum contents; (2) at least two other sample sets from the Galapagos area that represent samples with varying distance from the mantle anomaly that is responsible for the Galapagos archipelago; and (3) Two eruptive units close in age and location from the subaerial mid-ocean ridge exposed in Iceland. The Icelandic work will investigate samples erupted at different times during single eruption episodes, which will allow us to address eruptive processes in ways not possible in the Galapagos area. It also permits investigation of variations in mantle sources, melting conditions and magma evolution processes over short spatial (~20 km) and temporal (~400 years) scales.Broader Impacts: This work supports a faculty member and graduate student at the University of Hawaii. Student training will include a wide range of analytical and petrological techniques and theory, as well as an introduction to Icelandic geology. Undergraduate students will be involved in the preparation of rock samples for chemical and petrographic analysis. Results of this research will be incorporated into classroom teaching and community presentations and published in widely accessible peer-reviewed journal articles.

摘要（0524922）SINTON知识分子：该项目调查了控制中山岭火山岩的化学成分和矿物学的过程。 它特别解决了上升地幔熔化的变化如何影响原发岩浆的组成，以及这些岩浆在地壳和地幔中不同深度的冷却和结晶中如何改变化学和矿物学的变化。 这项研究结合了理论模型，对地壳厚度的地球物理约束以及来自加拉帕戈斯群扩散中心和冰岛西部火山区中山脊的天然样品的化学和岩石学分析。 这些对比样品集将允许评估扩散速率，地幔源成分，地幔温度，地壳厚度以及喷发样式的变化如何在特定位置沿散布山脊的特定位置在特定位置产生物理和化学变化。 这项工作涉及确定所选样品中各个矿物质（橄榄石，长石，辉石和氧化物）的相对比例，并分析这些矿物质的化学成分以及整岩样品的化学成分。 特定样品集包括：（1）来自加拉帕戈斯地区的异常海底熔岩，铝含量很高； （2）至少来自加拉帕戈斯地区的另外两个样品集，这些样品代表了距地幔异常距离不同的样品，该样品负责Galapagos群岛； （3）两个爆发单位的年龄和位置关闭了冰岛暴露于冰岛的次生山脊。 冰岛的工作将调查单次喷发发作期间在不同时间爆发的样品，这将使我们能够以加拉帕戈斯地区不可能以不可能的方式解决喷发过程。 它还允许调查在短空间（〜20 km）和时间（〜400年）尺度上的地幔源，熔融条件和岩浆演化过程的变化。Boader的影响：这项工作支持夏威夷大学的教职员工和研究生。 学生培训将包括广泛的分析和岩石学技术和理论，以及冰岛地质学介绍。 本科生将参与化学和岩石学分析的岩石样品的准备。 这项研究的结果将纳入课堂教学和社区演讲中，并在广泛访问的同行评审期刊文章中发表。