Volatiles in Tonga Arc Magmas

汤加弧岩浆中的挥发物

• 批准号: 0839061
• 负责人: Terry Plank
• 金额: $ 9.43万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0839061&HistoricalAwards=false
• 关键词: Volatiles; Tonga; Arc; Magmas

ABSTRACT (0526450) PlankIntellectual MeritOne of the most important chemical species in magmas, H2O, affects a host of scientific and societal problems related to volcanism at subduction zones. Water is critical not only to the physics of subduction and eruption, but also to the processes that lead to melting and magma production in the mantle. This project seeks to develop the first comprehensive study of the volatile content (H2O, CO2, SO2, Cl, F) of Tonga arc magmas, or order to test the hypotheses regarding: (1) the composition of slab fluids, (2) their distribution in the mantle, and (3) their effect on melting. The Tonga arc provides several well-defined tests of hypotheses relating to the highest tectonic plate convergence rate in the world, anomalously high mantle temperatures, and cross-strike compositional variations along more than 200 km, which includes volcanism in the Lau Basin. This project addresses questions of melting and mantle composition by measuring volatile concentrations in melt inclusions using both ion and electron microprobes. These data will be combined with major and trace element compositions from electron microprobe and laser-ICPMS. Data will be used to develop quantitative relationships between slab fluid compositions and mantle melting progress. Samples are currently in-hand from recent research cruises supported by Australian organizations, with continuous coverage of the 1000 km long, largely submarine Tonga arc. Broader ImpactsThis project complements the science plans of other major initiatives in NSF-GEO, including RIDGE 2000 in the Lau Basin, and the MARGINS Subduction Factory experiment. One important outcome will be a comprehensive phenocryst dataset from the Tonga arc area, which is poorly represented in current on-line databases. This project leverages infrastructure and ship-time costs contributed from Australian sources. Results from this project will be incorporated into the undergraduate and graduate classrooms at Boston University, and will support the Ph.D. thesis of a female graduate student and a new research direction for a senior female faculty members at Boston University in Massachusetts.

摘要（0526450）岩浆中最重要的化学物种的浮游生物占有一致，H2O影响了与俯冲区域的火山相关的许多科学和社会问题。 水不仅对俯冲和喷发的物理学至关重要，而且对导致地幔融化和岩浆产生的过程至关重要。 该项目旨在开发汤加（Tonga Arc Magmas）挥发性含量（H2O，CO2，SO2，CL，F）的首次综合研究，或者为了测试有关：（1）板液组成的假设，（2）它们在大概中的分布和（3）其对融化的影响。 汤加（Tonga Arc）提供了几项与世界上最高的构造板收敛速率有关的假设测试，异常高的地幔温度以及沿200公里以上的跨震动组成变化，包括Lau盆地的火山症。 该项目通过使用离子和电子微探针测量熔体夹杂物的挥发性浓度来解决融化和地幔组成的问题。 这些数据将与来自电子微探针和激光-ICPM的主要和微量元素组成结合使用。 数据将用于建立平板流体组成与地幔熔化进度之间的定量关系。目前，澳大利亚组织支持的最新研究巡游目前有样本，并连续覆盖了1000公里长的汤加潜艇。更广泛的影响，这一项目补充了NSF-GEO其他主要举措的科学计划，包括Lau盆地的Ridge 2000和Margins俯冲工厂实验。一个重要的结果将是来自汤加弧区域的全面的现场数据集，该数据集在当前的在线数据库中的代表很差。该项目利用澳大利亚来源造成的基础设施和船舶时间成本。该项目的结果将纳入波士顿大学的本科和研究生教室，并将支持博士学位。马萨诸塞州波士顿大学的一名高级女教师的女研究生和新的研究方向的论文。