Updated probabilistic seismic hazard assessment using M_wg (Das magnitude scale) to address moment magnitude (M) scale inaccuracies below 7.5: a case study from Northeast India.

ABSTRACT: This study uses the Das magnitude scale (M_wg) to improve probabilistic seismic hazard assessment (PSHA) in Northeast India, where traditional M scales introduce inaccuracies for events below M 7.5. The M scale is mathematically flawed in this range, being based on an equation derived for Ms ≲ 7.0-an inconsistency evident in the observed data. Using a unified earthquake catalog of 9,968 events, calibrated to M_wg, in conjunction with region-specific seismogenic zones and observed-data-validated ground motion models, hazard spectra were derived for 475- and 2475-year return periods. The resulting PSHA indicates maximum peak ground accelerations (PGA) of 0.908 g and 1.5405 g for 10% and 2% exceedance probabilities over 50 years, respectively. Comparative analysis revealed

SUBMITTER: Das R 

PROVIDER: S-EPMC12695893 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature