The U.S. Geological Survey 2025 Puerto Rico and U.S. Virgin Islands Time-Independent Earthquake Rupture Forecast

Kevin R. Milner; Alexandra E. Hatem; Richard W. Briggs; Jessica A. Thompson-Jobe; Andrea L. Llenos; Andrew J. Michael; Allison M. Shumway; Edward H. Field; Kirstie L. Haynie

doi:10.1785/0120250040

journal article Open Access Mar 16, 2026

The U.S. Geological Survey 2025 Puerto Rico and U.S. Virgin Islands Time-Independent Earthquake Rupture Forecast

Kevin R. Milner

Alexandra E. Hatem

Richard W. Briggs

Jessica A. Thompson-Jobe

Andrea L. Llenos

Andrew J. Michael

Allison M. Shumway

Edward H. Field Kirstie L. Haynie

Bulletin of the Seismological Society of America · Seismological Society of America (SSA)

View at Publisher Save 10.1785/0120250040

Abstract

ABSTRACT
We present the 2025 U.S. Geological Survey Puerto Rico and U.S. Virgin Islands (PRVI) time-independent earthquake rupture forecast (ERF), developed for the 2025 update to the National Seismic Hazard Model (NSHM) for PRVI. The updated ERF improves upon a prior model from 2003, including an expanded fault inventory with slip-rate estimates, updated seismicity catalogs, and refined subduction zone geometries and deformation models. It applies the fault-system inversion methodology to solve for rates of ruptures on modeled faults, adapted from the 2023 NSHM (NSHM23) for the western United States, including the first application of the inversion to model rates on a U.S. subduction interface. Off-fault and intraslab seismicity are constrained by observed seismicity and use updated methods developed for NSHM23. Uncertainties in model components are substantial, and the ERF represents epistemic uncertainties through a comprehensive logic tree consisting of 1.7 billion logic-tree branches combined across all sources.

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Published: Mar 16, 2026
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Authors

K

Kevin R. Milner

1Geologic Hazards Science Center, U.S. Geological Survey, Pasadena, California, U.S.A.

A

Alexandra E. Hatem