42cd6fcd-b5fd-4059-bc73-a1f6f852f7ae urn:uuid eng UTF-8 nonGeographicDataset nonGeographicDataset 2025-10-16T22:57:58 creation ISO 19115 2016 Probabilistic Seismic Hazard Analysis model for the Philippines 42cd6fcd-b5fd-4059-bc73-a1f6f852f7ae The Philippine archipalego is tectonically complex and seismically hazardous, yet few seismic hazard assessments have provided national coverage. This paper presents an updated probabilistic seismic hazard analysis for the nation. Active shallow crustal seismicity is modeled by faults and gridded point sources accounting for spatially variable occurrence rates. Subduction interfaces are modelled with faults of complex geometry. Intraslab seismicity is modeled by ruptures filling the slab volume. Source geometries and earthquake rates are derived from seismicity catalogs, geophysical datasets, and historic-to-paleoseismic constraints on fault slip rates. The ground motion characterization includes models designed for global use, with partial constraint by residual analysis. Shallow crustal faulting near metropolitan Manila, Davao, and Cebu dominates shaking hazard. In a few places, peak ground acceleration with 10% probability of exceedance in 50 years on rock reaches 1.0 g. The results of this study may assist in calculating the design base shear in the National Structural Code of the Philippines. {"type": "Polygon", "coordinates": [[[114.8607, 4.0396], [128.308, 4.0396], [128.308, 20.7972], [114.8607, 20.7972], [114.8607, 4.0396]]]} 114.8607 128.308 4.0396 20.7972 Earthquake Engineering Hazard Response Natural Hazards Pacific Nations Philippines Published_External earthquakes seismic hazard Link to article documentDigital Link to article HTML