Looking at the ‘Continent divided by water’: Coastal and human dynamics, and the potential for submerged landscapes in the Caribbean

Research on the history and archaeology of the Caribbean has demonstrated the overwhelming importance of commerce and long distance trading and social networks for the peopling and the social development of the lands circling the Caribbean Sea. Navigation - riparian or maritime - is paramount in this consideration because water is ubiquitous in the `water world' of the Caribbean Lowlands. The area includes the basins and deltas of two of the world's largest rivers, the Amazon and the Orinoco systems, and widely complex coastal plains stretching from northern Brazil and Surinam to Mexico, south Florida and the Caribbean Archipelago. The coastal dry land masses (continent or islands) are joined by water: rivers, swamps, marshes or the sea: a continent divided by water'. When the chronology of the social dynamics surrounding the Caribbean Sea are scrutinized, the pattern that emerges is of land - based economies and dispersed hunter - gatherer sites starting around 14kBP, but there is no evidence of settlement along the coasts or exploitation of marine resources until around 8kBP on the continents, or 7-5kBP on the islands. These dates coincide with a general sea level stabilization at 3-5 m below msl around 7kya. As sea level rose, shallow coastal areas flooded, transforming the hydrology, oceanography and morphology of the coastlines. Given the rate of eustatic sea-level rise during the Late Pleistocene and Early Holocene, much of the early coastal landscapes around the American continents and the Caribbean Islands should be currently submerged, along with the evidence of human use of ancient coasts. The dry sites we today assume as early reflect settlement patterns that correspond to a relatively late configuration of the coastal morphology. However, underwater archaeology in the Caribbean has mostly focused on wrecks, if on anything at all, with practically no attention being paid to drowned landscapes. No marine geophysics analysis has been applied to underwater archaeology in the Caribbean so far. Given that early evidence of human activity should be submerged and possibly buried, the application of acoustic remote sensing techniques is the most time and cost effective survey method. Among these, high-resolution multi-channel and 3D seismic reflection surveying, in particular 3D Chirp systems, have proven to be very useful for the investigation of drowned landscapes as they can provide detailed stratigraphic information and visualization of buried archaeological objects. Even though no local studies have been conducted yet, this presentation focuses on the northeastern corner of the Caribbean Archipelago, at the contact between the Greater and the Lesser Antilles (Mona Passage, Puerto Rico, Virgin Islands and the Anegada Passage), identifying areas with the highest potential for preservation of submerged landscapes and associated sites, from a geoarchaeological perspective. While side-scan sonars are useful to observe the sea floor and to identify shipwrecks or fishing technology, I emphasize on the potential of seismic surveys with sub-bottom profilers for the identification of buried ancient landscapes and associated sites, particularly in shallow, low-energy environments. This type of study and preliminary evaluation will serve as a basis to establish a solid collaborative research program that will permit a more complete understanding of the socio-natural dynamics of the peopling of the Caribbean region.