Location and Characterization of Ambient Seismic Noise Using USArray

使用 USArray 对环境地震噪声进行定位和表征

• 批准号: 0951558
• 负责人: Keith Koper
• 金额: $ 24.37万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0951558&HistoricalAwards=false
• 关键词: Location; Characterization; Ambient; Seismic; Noise

In this study, the PIs are analyzing data recorded by the hundreds of seismometers that constitute USArray; however, instead of studying signals from earthquakes, the PIs are analyzing seismic energy that is created by the interference and interaction of ocean waves. This process generates an ambient field of background noise, often referred to as microseisms, that can be used to image Earth's interior, and to detect changes in Earth structure related to volcanic and tectonic processes. In particular, the PIs are using the USArray as a giant, seismic antenna to locate and characterize microseismic sources throughout the world's oceans. Interestingly, many of the source regions occur in the deep waters of ocean basins, far away from the reflecting coastlines that are traditionally considered to be the dominant source of microseisms. Analysis of microseismic energy from these deep water sources has the potential to illuminate those portions of Earth's interior that are poorly sampled by earthquakes, which overwhelming occur in narrow belts along the boundaries of tectonic plates.

在这项研究中，pi正在分析构成USArray的数百个地震仪记录的数据；然而，pi不是研究地震信号，而是分析由海浪的干扰和相互作用产生的地震能量。这个过程会产生一个背景噪声的环境场，通常被称为微地震，可以用来成像地球内部，并探测与火山和构造过程有关的地球结构变化。特别是，pi正在使用USArray作为一个巨大的地震天线来定位和表征世界各地海洋的微震源。有趣的是，许多震源区域位于海洋盆地的深水区，远离传统上被认为是微震主要震源的海岸线。对来自这些深水源的微震能量的分析有可能照亮地球内部那些地震采样不足的部分，这些地震大多发生在沿构造板块边界的狭窄地带。