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

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，同时也带来了巨大的危险，尤其是在发展中国家。俯冲带中最不为人所知的问题之一是俯冲岩石圈与地幔过渡带之间的相互作用。特别是，横跨660公里不连续层的板块穿透量控制着上下地幔之间的热量和质量传递速率。这个过程对于理解地幔的热对流和化学混合至关重要，包括对原始地幔的持续探索。西南太平洋是研究俯冲板块命运的天然实验室，因为古老、寒冷的岩石圈的快速俯冲一直在进行，为理解板块- tz相互作用过程提供了充足的信号。此外，俯冲岩石圈内丰富的地震活动性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记录频繁事件的地震仪，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性的来源。最近发现，位于新喀里多尼亚努美阿的发展研究所（IRD）的Robert Pillet博士负责维护横跨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，而这正是地震活动丰富的地方，可以用来探测深俯冲带。Pillet和IRD-Noumea已经同意发布来自整个Cavascope网络的部分专有数据，供Brudzinski和Pillet进行几次原位实验，以促进对俯冲岩石圈如何与TZ底部相互作用以及深地震起源的理解。更广泛的影响包括在一个拥有高质量数据但完成科学项目的手段有限的发展中国家训练有素的科学家之间建立伙伴关系，以及在矿物物理学、地球动力学和地震学方面与其他研究人员进行更广泛的合作。将通过在迈阿密大学举办的一个独特的实地讲习班寻求进一步的影响，使学生获得实际的教育经验。

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.