Seismic Hazard & Ground Motions

Slate Geotechnical Consultants are experts in seismic source characterization, ground motion characterization, detailed site response analysis, seismic hazard and risk analyses across the United States and worldwide. We perform seismic hazard and seismic risk studies for commercial and residential sites such as high-rise and base-isolated buildings as well as critical structures such as dams, pipelines, hospitals, schools, and nuclear facilities. Our team utilizes the latest research and analysis methodologies to deliver quality results to our clients for informed decision-making and design. Slate routinely collaborates with structural engineers to provide and refine geotechnical input parameters for seismic analysis. We integrate the results of our seismic hazard assessments with our earthquake engineering practice to identify and characterize ground failure hazards that includes providing quantitative estimates of vertical and lateral ground displacements. Using these results, Slate provides critical information needed by our clients and designers to appropriately assess and mitigate seismic risk to their facilities.


  • Seismic source characterization
  • Ground motion characterization including traditional, partially ergodic and non-ergodic model development
  • Strong motion seismology
  • Probabilistic seismic hazard analysis (PSHA) including sensitivity studies and vertical hazard
  • Deterministic seismic hazard analysis (DSHA)
  • Development of conditional mean spectra
  • Ground motion directionality, directivity, pulses
  • Regulator/Code compliant response spectra development, including ASCE 7-16, 2019 CBC, and 2018 IBC
  • Site-specific time history selection and modification including spectrum compatible
  • Tsunami hazard analysis
  • Senior seismic hazard analysis committee (SSHAC) studies
  • Site response including equivalent linear, nonlinear and random vibration theory analyses
  • Peer review of seismic hazard studies

Representative projects