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

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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.