Expanding the volcano monitoring toolset with repetitive seismicity and seismic velocity changes

Earthquakes that share similar waveforms are a frequent feature of the seismicity at volcanoes. Studies suggest that temporal variations in the size, rate, and character of repeating seismicity are often correlated with other changes in a volcano’s behavior, therefore, rapid identification of trends or changes in the behavior of repeating earthquakes are an asset for volcano monitoring. I developed the software package “REDPy” to fill this need, and it is used at many volcano observatories to automatically detect and group earthquakes based on their waveform similarity. My research takes this a step further, analyzing subtle differences in the waveforms of pairs of repetitive earthquakes with coda wave interferometry to measure small temporal variations in the shallow seismic velocity structure. These seismic velocity changes are thought to be sensitive to strain, which could complement direct measurements of deformation for volcano monitoring. In this talk, I’ll discuss the application of these techniques to multiple volcanic datasets (i.e., Mount St. Helens, Long Valley, and recent eruptions in Hawai?i) and several considerations for their future operationalization.

Speaker: Alicia Hotovec-Ellis, US Geological Survey