Collaborative Research: Fingerprinting source-to-sink connections for deep-marine vitriclastic deposits and their association to caldera formation on Axial Seamount

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项目编号	1633936
	Collaborative Research: Fingerprinting source-to-sink connections for deep-marine vitriclastic deposits and their association to caldera formation on Axial Seamount
	Brian Dreyer
主持机构	University of California-Santa Cruz
项目开始年	2016
	2016-09-15
项目结束日期	2019-08-31
资助机构	US-NSF
项目类别	Standard Grant
项目经费	116318(USD)
国家	美国
语种	英语
英文摘要	The most active volcanic provinces in the world are under the sea. Because there is little interference from the thick crustal rocks that form the continents and because the magmas that erupt on the seafloor are closer to and more representative of their source in the mantle, submarine volcanic studies over the last 50 years have helped to transform our knowledge of magma and magma chamber dynamics and evolution. They have also improved our understanding of how the Earth and its tectonic plates work and the cycling of geochemical elements between crustal and mantle reservoirs and vice versa. This being said, with the exception of a few that peek above the ocean as islands, most seafloor volcanoes lie thousands of meters below the sea surface making it very difficult to know when or how they are erupting. This research will improve our knowledge of these processes by examining volcanically generated sediments deposited in and around the Axial Volcano caldera 1,400 meters below sealevel and about 500 km off the west coast of Oregon. The research is focused on understanding the history of Axial Volcano caldera formation and determining the mechanisms of vitriclastic formation and the applicability of their use in volcanic stratigraphic studies on undersea volcanoes. Axial is the most thoroughly monitored and sampled seamount in the world. Samples consisting of sediment cores, scoop bags, and rocks as well as bathymetric maps of the caldera at 1 meter resolution will be used in the analysis as will sedimentologic, stratigraphic, and geochemical analytical approaches. Broader impacts of the project include support of two early career scientists, graduate student training, and use of the new, major, NSF-funded Ocean Observing Initiative network. Impacts also include collaboration with two scientists whose gender is under-represented in the sciences, both of whom are employed at institutions in the EPSCoR states (i.e., states that do not receive significant amounts of federal funding) of Idaho and Rhode Island. Other impacts include international collaboration with German and French scientists and outreach to K-5 schools by producing materials for instruction on volcanoes and volcanic eruptions. Goals of the research are to define the physical and chemical evolution of Axial Seamount through the time of caldera formation and increase our understanding of submarine volcano eruption styles, fragmentation processes, and vitriclast dispersal mechanisms. Hypotheses to be tested include (1) the physical and chemical characteristics of vitriclastic deposits can be used to fingerprint their eruption, fragmentation, and dispersal origins and (2) lithofacies record magma reservoir deepening associated with magma withdrawal and caldera collapse.Technical The mineralogy of vitriclasts will be examined using X-ray diffraction and scanning electron energy dispersive spectroscopy to constrain their temperature and chemical conditions of origin. Stable isotopes of Hydrogen and Oxygen as well as Cl/K2O ratios will be used to determine magma-seawater interaction during vitriclast fragmentation and seawter assimilation into the magma. A detailed morphometric, textural, and grain size analysis will be carried out to determine if clasts are of phreatomagmatic origin. Magmatic volatiles will be measured in 80 glass inclusions in olivine by secondary ion mass spectrometry from samples taken from vitriclasts.
来源学科分类	Geosciences - Ocean Sciences
文献类型	项目
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/70379
专题	环境与发展全球科技态势
推荐引用方式 GB/T 7714	Brian Dreyer.Collaborative Research: Fingerprinting source-to-sink connections for deep-marine vitriclastic deposits and their association to caldera formation on Axial Seamount.2016.