biostudies-literatureUnknown15(1)Das RThis 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 revealedScientific reports43502https://www.ebi.ac.uk/biostudies/studies/S-EPMC12695893biostudies-literatureUpdated probabilistic seismic hazard assessment using M<sub>wg</sub> (Das magnitude scale) to address moment magnitude (M) scale inaccuracies below 7.5: a case study from Northeast India.PMC12695893Choudhury DMeneses CDas RAlam MABarrera FGDas AWason HRfalseUpdated probabilistic seismic hazard assessment using M<sub>wg</sub> (Das magnitude scale) to address moment magnitude (M) scale inaccuracies below 7.5: a case study from Northeast India.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 revealed2025-01-01T00:00:00Z2025 Nov2026-06-06T00:22:46.641Z2026-05-23T03:14:16.14ZS-EPMC126958934131032510.1038/s41598-025-06642-1