Geology of Barbados

The island of Barbados is approximately 150 km east of the Lesser Antilles magmatic island arc and is the only subaerially exposed pan of the Barbados Ridge accretionary prism. The oldest rocks on Barbados are exposed in the Scotland District as pelagic shales, sandstones, and siltstones' ash layers, chalks, and radiolarites. These rocks are complexly folded and faulted mainly due to Late Tertiary to Quaternary compressional deformation and uplift. Except for the highlands, the deformed Tertiary strata are unconformably overlain by a succession of Pleistocene, tectonically little affected, reef terraces that topographically downstep toward the northern, eastern and southern coastlines almost concentrically becoming younger toward the coastline. The Upper Reef Terrace is older than 600 000 years whereas the youngest reef terrace submerged off the Lower Reef Terrace is of Holocene-Recent age. The terraces formed in response to tectonic uplift and eustatic sea-level fluctuations that resulted in several episodes of relative sea-level drop.

Pleistocene reef terrace

Holocene and Recent Reefs