ANS-2.27-2020(R2025)

This standard provides criteria and guidelines for conducting geological, seismological, geophysical, and geotechnical investigations needed to provide information to support the following: (1) seismic source characterization input to a probabilistic seismic hazard analysis (PSHA); (2) evaluation of tectonic permanent ground deformation (PGD) hazard using probabilistic fault displacement hazard analysis (PFDHA) for surface-faulting sources and probabilistic tectonic deformation hazard analysis (PTDHA) for blind fault sources; (3) site response analysis input to PSHAs; (4) nontectonic, earthquake-induced ground failure hazard; (5) foundation stability.