Bahamas

The Bahamas archipelago occupies one of the most geologically stable portions of the Caribbean region, situated on the Bahama Platform — a thick accumulation of carbonate sediments up to 10 kilometres deep resting on old, rigid continental and oceanic crust. This geological stability translates into very low indigenous seismicity; the Bahamas themselves do not generate significant earthquakes. The primary seismic hazard the islands face is not from local faulting but from the transmission of [[seismic-wave]]s originating at the active plate boundaries to the south and west. The Cuba-Hispaniola corridor lies within several hundred kilometres, and the Puerto Rico Trench — capable of hosting great subduction earthquakes — lies to the southeast. These distant sources can deliver both shaking and [[tsunami]] energy to the low-lying islands. The passive Atlantic margin to the east represents a geologically ancient boundary with minimal modern seismic activity.

Historical accounts from the Bahamas do not record locally generated destructive earthquakes, reflecting the genuine stability of the Bahama Platform. However, the islands have felt shaking from distant regional events. The 2010 Haiti earthquake (magnitude 7.0) was felt in Nassau and other populated islands, and the January 2020 Puerto Rico earthquake sequence (including a magnitude 6.4 mainshock) produced felt motion across much of the Bahamas. The most significant historical threat from a seismic-related hazard was the [[tsunami]] generated by the 1755 Lisbon earthquake, which produced measurable wave heights across the Atlantic basin, though Caribbean attenuation reduced its impact significantly by the time it reached the Bahamas. Regional tsunami events from the Caribbean plate boundaries remain the primary long-term concern.

Geologically, the Bahamas sit at the eastern edge of what was once the interior of the supercontinent Pangaea. When the Atlantic began opening during the Jurassic period approximately 180 million years ago, the Bahama Platform formed as a shallow-water carbonate factory, accumulating limestone and dolomite over tens of millions of years. The platform never experienced significant compressional or extensional tectonics after that rifting phase concluded, leaving it as a geologically quiescent region today. The tectonic boundary between the North American Plate — on whose trailing margin the Bahamas sit — and the Caribbean Plate lies to the south and west along the Cuba-Cayman strike-slip system. [[seismic-wave]]s from events on that boundary can travel efficiently through the cold, rigid lithosphere and arrive in the Bahamas with limited attenuation.