Collaborative Research: Imaging the Mantle in the Central American Subduction Factory

该合同是对在尼加拉瓜和哥斯达黎加部署43台PASSCAL宽带地震仪的18个月的奖励，以对该地区中美洲火山弧的地幔“俯冲工厂”进行地震成像。除PASSCAL仪器外，PIS还将与哥斯达黎加和尼加拉瓜地震学家合作，利用现有的短周期和宽带仪器的数据。该实验将用接收函数和其他转换波成像地幔楔形，以及区域波形反演。层析成像将被用来试图绘制地幔楔形区域中板块脱水(和中等深度地震产生)、熔体产生和熔体迁移的区域。从横波分裂数据将解释地幔流动的模式，并将从接收函数推断地壳结构。总体而言，这个想法是通过结合地壳和地幔的地震图像以及对弧形火山沿走向观察到的岩浆成分巨大差异的模拟解释来推断俯冲工厂的工作原理。

This award is for an 18 month deployment of 43 PASSCAL broad band seismometers in Nicaragua and Costa Rica to seismically image the mantle "subduction factory" of the Central American volcanic arc in the region. In addition to the PASSCAL instruments, the PIs will also collaborate with Costa Rican and Nicaraguan seismologists to use data from existing short period and broadband instruments. The experiment will image the mantle wedge with receiver functions and other converted waves, together with regional waveform inversions. Tomographic imaging will be used to try to map the region of slab dewatering (and intermediate depth earthquake generation), melt generation and melt migration in the mantle wedge. Patterns of mantle flow will be interpreted from shear wave splitting data, and crustal structure will be inferred from receiver functions. Overall, the idea is to infer the workings of the subduction factory by combining seismic images of the crust and mantle with the modeled interpretations of large observed differences in magma composition along strike in the arc volcanoes.