Infrasonic Hotspot Mapping and Atmospheric Probing with the USArray

美国阵列公司的地震仪不仅直接测量地面运动，还间接提供有关影响地面运动的其他现象的有价值的信息。例如，已知地震仪可以通过声-地震转换来检测次声，即低于~20赫兹的低频声音。次声事件通常用全局间隔的次声阵列来定位。最近的研究表明，尽管场地条件可能不同，但美国阵列地震台站的密度使人们能够以更高的精度和高度分辨率来定位震源。该项目将在以前工作的基础上扩展，以探测和定位2008年期间由美国气象局登记的100多个高质量次声事件。该项目的目标是确定在六年的时间跨度内产生美国阵列公司注册的次声信号的事件的发生、位置和频率，从而建立一个独特的大陆范围的次声事件研究数据库。该项目的第二个组成部分是阐明其中几个事件的次声传播时间分支，这可能提供对次声传播的非凡见解以及对最先进的大气速度模型的测试。最后，我们将分析探测趋势，并基于之前2008年的结果检验现有的大气传播假说。

The seismometers of the USArray not only directly measure ground motion, they also indirectly provide valuable information about other phenomena that affect ground motion. For example, it is known that infrasound, low-frequency sound below ~20 Hz, can be detected by seismometers through acoustic-to-seismic conversion. Infrasound events are usually located with globally spaced infrasound arrays. It has been recently shown that the density of USArray seismic stations permits one to locate sources with much greater accuracy and with altitude resolution, despite probable variations in site conditions. This project will expand upon previous work on the detection and location of more than one hundred high-quality infrasonic events that were registered by the USArray during 2008. The goal of this project is to identify the occurrence, location, and frequency of events that produced USArray-registered infrasonic signals over a time span of six years, resulting in a unique continental-scale infrasonic events research database. The second component of the project is to illuminate the infrasonic travel time branches for several of these events, which may provide both remarkable insights into infrasonic propagation as well as a test of the state-of-the-art atmospheric velocity models. Finally, we will analyze detection trends and test an existing atmospheric propagation hypothesis based on the previous 2008 results.