Location and Characterization of Ambient Seismic Noise Using USArray

University Of Utah, Salt Lake City UT

Investigators

Abstract

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.