Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


This dissertation presents the geographical transformation registered in the San Juan Bay, Puerto Rico, and its surroundings. Emphasis has been given to the human impact, originated by various cultural groups, on the landscape. Stratigraphical and sedimentological analysis, as well as geological documentation have been used to reconstruct the geological history of the Bay, which is characterized by a series of volcanic rock formations followed by another series of sedimentary depositions. Subsequently, sea level changes and tectonic movements have altered these depositions, giving rise to an estuarine system. The geographical history of each cultural period has been reported with the help of historical documents and maps, as well as with data compiled in the field. These three periods are: the Indian Period, characterized by the successive presence of the Igneri, Arawak, and Taino Indians between 300-1530 AD; the Colonial Period, dominated by the Spaniards from 1508 to 1898, and including the arrival of the Negroes after 1530; and the premodern-modern period, marked by the strong influence of the North Americans. The last forty years' landscape changes have been reproduced via remote sensing techniques, field verification and personal interviews. Human activities have directly affected those aspects associated with the geomorphology, oceanography, biogeography and climatology of the area. These changes came as a result of landfills, dredges and vegetational cutoff, among others. All this human activity has modified the bay's natural processes, such as erosion, deposition, and water circulation. Cartographic, remote sensing, statistical interpretation and historical analysis have been the principal methods used to determine the impact of human occupancy. As a result of thse human activities, the coastal morphology and the bathymetry of the bay have been altered, destroying old coastal features in some parts and creating new ones in others. Climate has probably been modified through the increase of annual temperature and variation in the precipitation patterns. Based on the investigation it can be inferred that the human influence on the geographical evolution of the zone has been much more significant than that of any natural element. Approximately 85% of the original landscape has been transformed into a human scenery.