Collaborative Research: Near-Field Volcano Infrasound: Three-dimensional Seismo-Acoustic Wave Propagation

通过理论计算和现场观测相结合，实现了一个详细的、现实的程序来模拟近场火山爆发的三维地震声波传播。通过对厄瓜多尔通古拉瓦火山15站30单元阵列的爆炸记录，建立了基于风切变和地形效应模型的理论预测测试。全波形模拟与地形的三维分布的真实表示被用来模拟声波在大气中的传播以及弹性波在地球上的传播。对于爆炸，震源时间函数可以从声波中导出，从而对高保真地震波记录的震源效应进行反卷积。地震信号用于提取火山结构和导管的详细地质结构，以及熔体百分比、粘度、气-流-固相分配等物理参数。

A detailed, realistic program to model three-dimensional, seismo-acoustic wave propagation from an exploding volcano in the near field is achieved by combining theoretical calculations and field observations. A test of theoretical predictions based on models of wind shear and topographic effects is established by recording explosions on a 15 station 30 element array at Tungurahua Volcano, Ecuador. Full waveform simulations with realistic representations of three-dimensional distributions of topography are used to model acoustic wave propagation in the atmosphere as well as elastic wave propagation in the earth. For explosions, source time functions may be derived from acoustic waves to deconvolve source effects from hi-fidelity seismic wave recordings. Seismic signals are used to extract detailed geologic structure in the volcano edifice and conduit, as well as physical parameters such as melt percentage, viscosity, and partitioning of gas-fluid-solid phases.