Aruba

Aruba is a constituent country of the Kingdom of the Netherlands situated in the southern Leeward Antilles, approximately 29 kilometres north of the Venezuelan coast. It lies near the boundary between the Caribbean Plate and the South American Plate, a diffuse zone of compressional and strike-slip deformation that runs along the northern coast of South America. Unlike the active volcanic arc of the Lesser Antilles, Aruba is part of the ABC islands (Aruba, Bonaire, Curaçao), geologically distinct terranes composed of oceanic basement, mafic intrusions, and sedimentary cover that formed during the Cretaceous as fragments of the Caribbean oceanic plateau. The island is not underlain by an active subduction system in the conventional sense; the nearest plate boundary to the north is the Caribbean-South American transpressional zone, which generates moderate seismicity in northwestern Venezuela and the Dutch Leeward Islands region. Seismic hazard for Aruba is considered low to moderate — lower than the volcanic arc to the northeast but non-negligible given proximity to Venezuelan fault systems.

Aruba's earthquake history is characterised by occasional felt events from regional sources rather than locally generated destructive earthquakes. The ABC islands region experiences periodic M4–5 earthquakes associated with faulting within the Caribbean-South American boundary zone. In 1900, a damaging earthquake struck the western Venezuelan coast and was felt in Aruba and Curaçao. The 1812 Caracas earthquake (estimated magnitude 7.9), one of the most destructive earthquakes in South American history, generated [[seismic-wave]]s felt across the southern Caribbean. More recently, moderate earthquakes from the Venezuelan interior — including events on the El Pilar Fault system and the Oca-Ancón Fault — are regularly detected in Aruba. The island's low relief and carbonate-sand coastal margins create some susceptibility to [[tsunami]] from distant Caribbean events, though local fault generation of tsunamis is not a primary concern.

The geology of Aruba reflects its origin as part of the Caribbean Large Igneous Province, a vast oceanic plateau of basaltic and gabbroic rocks emplaced during the Cretaceous. Aruba's Cretaceous basement is overlain by Paleogene and Neogene sedimentary rocks, coral limestone, and aeolian dune deposits. The island experiences mild [[seismic-wave]] attenuation due to its position on relatively cold, old oceanic crust rather than the thermally weakened crust beneath the active volcanic arc. Ground motion amplification on coastal sandy soils is the primary site-response concern for engineering purposes. Seismic monitoring near Aruba is carried out through networks in the Netherlands Antilles and the Venezuelan seismological network (FUNVISIS), which maintains stations on the Venezuelan coast.