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Alicia J. Hotovec-Ellis, PhD

I am a volcano seismologist who is focused on improving the way we recognize, monitor, and respond to volcanic unrest. I use and develop new tools to rapidly detect and better understand seismic signals generated by volcanoes such as earthquake swarms and tremor.

I have two roles at the California Volcano Observatory (CalVO): fundamental science research on volcanic seismicity and monitoring of California’s volcanoes. My research focuses on understanding physical processes at volcanoes through the entire cycle of eruption and repose using a variety of seismological methods.

Major themes in my research are:

  • Recognition of unrest and changes in eruptive character
  • Genesis of earthquake swarms and volcanic tremor
  • Integration of interdisciplinary geophysical and geological datasets into seismic interpretations

The methods I use include waveform cross-correlation and clustering, precise relative relocation, coda wave interferometry, spectral analysis, and machine learning, among many others. I enjoy working on eruption datasets and often revisit older data to find new and unexpected observations that supplement our knowledge of what occurred and why.

I develop software for improving the way we seismically monitor volcanoes by bringing ideas from the literature into production for routine monitoring. I'm interested in the integration of interactive and automated data display so scientists responding to crises spend less time assembling data and more time interpreting it.

I lead the monitoring team at CalVO, and work with the Northern California Seismic Network to keep California’s volcanoes under constant surveillance. My goal is to ensure the necessary equipment and monitoring capabilities are already in place when the next Californian eruption occurs. I also assist other USGS volcano observatories and the Volcano Disaster Assistance Program with capacity building, data analysis, and eruption response assistance.

My interest in volcanoes began at a young age, and my career made possible through the support and mentorship of USGS scientists. As a result, I believe strongly in the value of both public outreach and mentoring for students and early career researchers.


*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government