SGER: International Collaboration for Study of Deep Subduction Using Seismic Arrays in New Caledonia and Vanuatu

SGER：利用新喀里多尼亚和瓦努阿图地震台阵研究深俯冲的国际合作

• 批准号: 0542253
• 负责人: Michael Brudzinski
• 金额: --
• 依托单位: Miami University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-15 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0542253&HistoricalAwards=false
• 关键词: SGER; International; Collaboration; Study; Deep

Subduction zones are a fundamental feature of the plate tectonic engine that drives theevolution of the Earth in addition to posing a great hazard, particularly in developing countries. One of the most poorly understood issues in subduction zones is the interaction between subducted lithosphere and the mantle transition zone (TZ). In particular, the amount of slab penetration across the 660-km discontinuity controls the rate of heatand mass transfer between the upper and lower mantle. This process is central to understanding thermal convection and chemical mixing of the mantle, including the continual search for a primordial mantle. The southwest Pacific presents a natural laboratory to examine the fate of subducted plates, as rapid subduction of old, cold lithosphere has been on-going to provide ample signal for understanding the slab-TZ interaction process. Moreover, abundant seismicity within the subducting lithosphere emits seismic waves that can illuminate properties and structure of the subduction zone. The only problem restricting studies in this region has been the lack of seismometers to record the frequent events, leaving researchers with limited means to directly sample the subducting slabs and examine the source of seismicity. It has recently come to light that Dr. Robert Pillet at the Institut de Recherche pour le Developpement (IRD) in Noumea, New Caledonia has been responsible for maintaining the Cavascope array of broad bandwidth (high-resolution) seismic instruments across New Caledonia and Vanuatuprecisely where abundant seismicity can be used to probe the deep subduction zone. Pillet and the IRD-Noumea have agreed to release a portion of proprietary data from the entire Cavascope network for Brudzinski and Pillet to perform several in situ experiments to advance the understanding of how subducted lithosphere interacts with the bottom of the TZ and the origin of deep earthquakes. Broader Impacts include a partnership between a well-trained scientist in a developing nation with high-quality data but limited means for completing scientific projects, as well as a broader collaboration with other researchers in mineral physics, geodynamics, and seismology. Further impact will be sought through a unique field workshop at Miami University in which students receive realistic hands on educational experiences.

俯冲带是板块构造引擎的一个基本特征，它驱动着地球的演化，并构成巨大的危险，特别是在发展中国家。俯冲带中最缺乏了解的问题之一是俯冲岩石圈和地幔过渡带（TZ）之间的相互作用。特别是，在660公里的不连续性板渗透量控制的热量和质量之间的上地幔和下地幔的传输速率。这个过程是理解地幔热对流和化学混合的核心，包括对原始地幔的持续寻找。西南太平洋提供了一个天然的实验室来研究俯冲板块的命运，因为旧的，冷的岩石圈的快速俯冲一直在为理解板-TZ相互作用过程提供充足的信号。此外，俯冲岩石圈内丰富的地震活动发出的地震波可以阐明俯冲带的性质和结构。限制该地区研究的唯一问题是缺乏地震仪来记录频繁的事件，使研究人员无法直接对俯冲板块进行采样并检查地震活动的来源。最近有消息称，新喀里多尼亚努梅阿发展研究所的Robert Pillet博士一直负责维护新喀里多尼亚和瓦努阿图的Cavascope宽带宽（高分辨率）地震仪器阵列，以便精确地探测可利用丰富地震活动探测深俯冲带的地点。Pillet和IRD-Noumea已同意发布整个Cavascope网络的一部分专有数据，供Brudzinski和Pillet进行几项原位实验，以促进对俯冲岩石圈如何与TZ底部相互作用以及深源地震起源的理解。更广泛的影响包括发展中国家训练有素的科学家与高质量数据但完成科学项目的手段有限的科学家之间的合作，以及与矿物物理学、地球动力学和地震学领域其他研究人员的更广泛合作。进一步的影响将通过在迈阿密大学的一个独特的实地研讨会，学生获得教育经验的现实手中寻求。