Ambient Noise Tomography in the Western US using Data from the EarthScope/USArray Transportable Array

The teleseismic transmission of seismic surface waves from earthquakes results in a loss of the high frequencies needed to infer information about Earth’s crust and uppermost mantle. A recent innovation in seismic imaging based on using long time sequences of ambient seismic noise moves beyond some of the limitations imposed on earthquakebased methods to reveal high resolution information about the crust and uppermost mantle. This method is called Ambient Noise Tomography (ANT) and has been applied predominantly to seismic surface waves. The application of ANT to data from ambitious new deployments of seismic arrays, such as the EarthScope USArray in the United States, has led to the development of large-scale seismic models of the earth’s crust and uppermost mantle at unprecedented resolution. In addition, new methods of data analysis and interpretation of ambient noise data that exploit the array nature of the TA are currently under development and hold out the promise for more reliable information about crustal and uppermost mantle anisotropy