Studying Eruptions and Lava Flows on Ontong Java Plateau with High-Precision Glass Chemistry

大型火成岩省，如华盛顿州的斯内克河平原或印度的德干圈闭，代表了地幔中大量玄武岩的喷发，是陆地和海底的突出地质特征。由于其巨大的规模和喷发时释放的大量还原流体和其他挥发物，这些喷发序列对当地和全球的环境和大气条件产生重大影响。太平洋上的Ontong爪哇高原就是其中之一，它几乎完全在水下喷发，影响了全球海洋化学。本研究开发了新的方法来确定在Ontong爪哇熔岩流的长度，体积，持续时间，风格和深度。海洋钻探计划采集的玄武岩玻璃岩心样品将通过非常精确的电子探针、FTIR和激光烧蚀ICPMS分析挥发性物质（Cl， S, H2O, CO2）。还将分析主要元素和微量元素。统计方法将用于确定不同的样品是否来自相同的流场和/或喷发。钻孔内和钻孔之间的样品将进行比较。目标是确定单个熔岩流是否可以追踪数百公里，并利用这些信息来限制熔岩流的大小和就位率。这项工作的更广泛影响包括一个大型的服务学习组件，将吸引本科生和K-12学生，以及开展一个创新的模拟海洋学航行，将研究和教育结合起来，影响100多名本科生。在其他劳动力发展方面，研究生将接受培训，学生将被带到专业协会会议上展示他们的工作成果。其他影响包括将向EPSCoR州（俄克拉荷马州）的一个机构提供资金，与德国科学家进行国际合作，以及对挥发性数据进行实验室间校准。这项工作的结果是对美国国家科学基金会资助的海洋钻探计划的补充。

Large igneous provinces, like the Snake River Plain in Washington State or the Deccan Traps of India, represent huge outpourings of basalt from the mantle and are prominent geologic features of the land and seafloor. Due to their immense size and the vast amount of reduced fluids and other volatiles they release upon eruption, these eruptive sequences have major impacts on local and global environmental and atmospheric conditions. The Ontong Java Plateau in the Pacific Ocean is one of these provinces and was erupted almost entirely underwater where it affected global ocean chemistry. This research develops novel new methods for determining the length, volume, duration, style, and depth of lava flow emplacement at Ontong Java. Samples of basaltic glasses from cores collected by the Ocean Drilling Program will be analyzed for volatile species (Cl, S, H2O, CO2) by very precise electron microprobe, FTIR, and laser ablation ICPMS. Major and trace elements will also be analyzed. Statistical methods will be used to determine if different samples are from the same flow field and/or eruption. Samples both within and between drill holes will be compared. Goals are to determine if individual lava flows can be traced hundreds of kilometers and to use this information to constrain lava flow size and emplacement rates. The broader impacts of the work include a large service-learning component that will engage undergraduates with K-12 students, as well as carry out an innovative simulated oceanographic voyage that will integrate research and education and impact over 100 undergraduates. In terms of other workforce development, a graduate student will be trained and students will be taken to professional society meetings to present the results of their work. Additional impacts include the fact that funds will be provided to an institution in an EPSCoR state (Oklahoma), international collaboration with German scientists, and the interlaboratory calibration of volatile data. Results of the work are complementary to those of the NSF-funded Ocean Drilling Program.