Christie Hale, PhD

Christie’s area of expertise is in probabilistic seismic hazard analysis, development of site-specific ground motions, and use of seismic hazard assessments in performance-based earthquake engineering evaluations and risk analyses. This work spans the spectrum from utilizing off-the-shelf results from simplified regional models to performing site-specific seismic hazard assessments that incorporate data from local geophysical investigations and ground motions recorded at the site. Her project portfolio includes developing site adjustment factors for hard rock dam sites in the Sierra Nevada region of California, performing a seismic hazard assessment for the seismic stability evaluation and remedial design of the mud pit caps on Amchitka Island in Alaska, and conducting a technical review of a site-specific seismic hazard assessment for a dam site in Iceland. With the move toward risk informed decision making, she has increasingly been supporting clients by developing seismic hazard assessments that fit into a risk framework.

Christie specializes in understanding and explaining the results of seismic hazard assessments and was recently engaged by a client to examine the results of an updated seismic hazard assessment for a portfolio of more than 150 dams. The project involved comparing the ground motions from the updated assessment to those from previous seismic hazard assessments, identifying trends in the ground motion comparisons, and attributing changes in the ground motions to specific changes in the seismic design criteria, seismic source model, ground motion models, and site response analyses. Prior to joining Geosyntec, she led the Probabilistic Seismic Hazard Analysis Code Verification project at the Pacific Earthquake Engineering Research Center, where her ability to understand how different modeling approaches impact the resulting seismic hazard curves was instrumental in helping participants troubleshoot their codes and reach consensus answers.

To advance the state of the practice, Christie is a key contributor to HAZ45, an open-source probabilistic seismic hazard analysis computer program used by hazard analysts in California and around the world. Recognizing that seismic hazard assessment is a rapidly evolving field, she is continuously evaluating and implementing new models and capabilities to stay at the forefront of advances in research and practice, ultimately allowing her to provide clients with the very best ground motion estimates supported by science.

Contact Christie at This email address is being protected from spambots. You need JavaScript enabled to view it.