New Seafloor Sampling Methods for Noble Gases: A Trial at Loihi Seamount

智力优势：这项研究评估了样品收集和处理过程中（船上和实验室）海底火山玻璃大气污染的重要性。 将使用一种新开发的新型气密取样器从夏威夷的Loihi海山采集样本，这种取样器可避免暴露在空气中。 海底玻璃提供了地幔稀有气体的重要档案，这些气体是地幔脱气和循环的关键指标。不幸的是，重惰性气体，特别是潜艇玻璃中氩和氙的同位素的表征受到大气污染的阻碍。 目前，污染的机制尚不清楚。这项研究测试的假设，大多数空气污染的样品处理和储存过程中引入，它可以避免一个新的采样协议，包括无空气处理。 该项目涉及使用加压容器从海底岩石中收集火山玻璃，随后将样品转移到纯氮气氛中，然后转移到特殊的真空容器中进行分析。 惰性气体在实验室中粉碎和/或熔化后，将通过质谱法进行测量。 分析结果将与使用常规方法（即暴露于空气中）收集的相同样品的分离结果进行比较。 实验还将检查污染是否与玻璃泡有关。 更广泛的影响：主要的更广泛影响将是为含有惰性气体的海底火山玻璃制定新的无空气采样和分析协议。 新设计的采样器可能应用于其他需要在高压下进行气密采样的领域，例如微生物学。 工作涉及两岸机构合作，并将支持研究生和本科生的培训。 伍兹霍尔海洋研究所将建立一个网站，供公众查阅研究成果。

Intellectual Merit: This research evaluates the importance of atmospheric contamination of seafloor volcanic glasses during sample collection and processing (both on the ship and in the laboratory). Samples will be collected from Loihi Seamount, Hawaii using a novel, newly developed, air-tight sampler that eliminates exposure to air. Submarine glasses provide important archives of mantle noble gases which are key indicators of mantle degassing and circulation. Unfortunately, the characterization of the heavy noble gases, particularly the isotopes of argon and xenon in submarine glasses has been hampered by atmospheric contamination. At present the mechanism of contamination is unknown. This research tests the hypothesis that most air contamination is introduced during sample processing and storage and that it can be avoided by a new sampling protocol involving air-free handling. The project involves collecting volcanic glasses from rocks on the seafloor using a pressurized vessel and subsequently transferring samples to a pure nitrogen atmosphere and then into special vacuum containers for analysis. Noble gases will then be measured by mass spectrometry after crushing and/or melting in the laboratory. Analytical results will be compared to splits of the same samples collected using conventional methods, i.e. exposed to air. Experiments will also examine whether contamination is related to glass vesicularity. Broader Impacts: The primary broader impact will be the development of new air-free sampling and analytical protocols for seafloor volcanic glasses containing noble gases. The newly designed sampler may have possible application to other fields that require air-tight sampling at high pressures, such as microbiology. Work involves bi-coastal institutional collaboration and will support graduate student and undergraduate training. A website allowing public access to research results will be created at the Woods Hole Oceanographic Institution.