Expert in earthquakes, earth structure, and seismic hazard.
- Earth structure
- Seismic hazard
- San Andreas fault
- Cascadia fault
- Serves on National Earthquake Prediction Evaluation Council
- Former director of the Pacific Northwest Seismic Network at the U of Washington (2006-2017)
- Former director of the Institute for Geophysics and Planetary Physics at UCLA (2002-2006)