Origin and Deformation of the Ontong Java Plateau

翁通爪哇高原的起源和变形

• 批准号: 1459152
• 负责人: Brian Savage
• 金额: $ 32.24万
• 依托单位: University of Rhode Island
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-15 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1459152&HistoricalAwards=false
• 关键词: Origin; Deformation; Ontong; Java; Plateau

The Ontong Java Plateau (OJP) covers 2 million km2 of seafloor, made up of 100 million km3 lavas that erupted rapidly ~120 Ma. This event represented a major heat and mass transfer from the Earth's deep interior to the surface. The cause of this magmatic event and the associated deformation of the plate on which this large load was emplaced are unclear. Recent work by these scientists has identified seismic structure in the mantle beneath the OJP that can only be explained by rock composition that would correspond to recycled oceanic crust. If true, this would suggest that subducted oceanic plates do not complete assimilate in the deep Earth. At least portions can survive the high temperatures and pressures and be caught up in global mantle circulation. Validating the presence of a mechanically strong mantle root beneath the OJP with quantitative estimates of its physical and chemical characteristics is expected to further understanding of the evolution of the oceanic lithosphere and the formation and survival of continental cratonic keels.A team of scientists from Japan, UK, and US are deploying ocean-bottom seismometers, electromagnetometers, and land based seismic stations on and around the Ontong Java between 2014-2016. This project supports US scientists and students to participate in onshore seismic data collection and analysis of the full amphibious dataset. All the seismic data for the combined projects will be shared among all the team and analyzed in collaboration. The US scientists will conduct advanced seismic analysis using 3-D full-wave tomography, and characterizations of anisotropy and attenuation. The new results would achieve 1° resolution, much improved over the current ~5° resolution that has led to contrasting interpretations of the distribution of low velocity within the OJP root. Teaching modules will be created and made available at Carleton College's On the Cutting Edge Geoscience site. Aspects of the data, analysis techniquest, and interpretation will be incorporated in undergraduate and graduate courses.

ONTONG JAVA高原（OJP）覆盖了200万公里的海底，由1亿km3熔岩组成，迅速爆发〜120 mA。该事件代表了从地球深内部到表面的主要热量和质量转移。此岩浆事件的原因和该大载荷被放置的板的相关变形尚不清楚。这些科学家的最新工作已经确定了OJP下地幔中的地震结构，只能用与回收的海洋壳相对应的岩石成分来解释。如果是真的，这表明俯冲的海洋板在深地球上不会完全同化。至少一部分可以在高温和压力中幸存下来，并陷入全球地幔循环中。预期其物理和化学特征的定量估计，预计验证机械性强的地幔根源在OJP下方，将进一步了解海洋岩石圈的演变以及一个来自日本，英国及我们在陆上范围内的科学家的科学家团队的形成和存活。 2014-2016。该项目支持美国科学家和学生参与陆上的地震数据收集，并分析完整的两栖数据集。合并项目的所有地震数据都将在所有团队中共享并在协作中进行分析。美国科学家将使用3-D全波断层扫描以及各向异性和衰减的特征进行高级地震分析。新的结果将达到1°的分辨率，比当前〜5°的分辨率大大改善，这导致了OJP根部低速分布的​​对比解释。教学模块将在Carleton College的尖端地球科学网站上创建并提供。数据，分析技术和解释的各个方面将纳入本科和研究生课程。