Development of a Depositional Model and Stratigraphy for the Islands of the Bahamas: The Importance of the Research Facility Founded by Don and Kathy Gerace

In 1977, we began to teach field courses on modern carbonates at the Gerace Research Centre (GRC) on San Salvador Island, Bahamas. Although the Bahamas was well-known for the study of modern carbonate deposition as a model for that of past epicontinental seas, there was little geological investigation of the islands themselves. In 1984, Don and Kathy Gerace provided us support for six weeks of geological reconnaissance mapping of the rocks along the island's entire perimeter, and all quarries, roadcuts, clifflines, offshore cays, and numerous karst features. Because of San Salvador's location on a small tectonically stable and isolated bank, subjected to glacio-eustatic sea-level changes, the geology had to be explained within those constraints of space and time. The result was our stratigraphic and depositional model for San Salvador Island, first presented to the larger geological community during a 1985 pre-annual GSA meeting field trip hosted by the GRC. One of the important results of our work was the clear demonstration of significant transgressive eolianite deposition during the rise of sea level associated with an interglacial. Previously, based largely on work done in Bermuda, eolianite deposition was assumed to occur mostly during the regression as sea level fell at the end of an interglacial.

Another major impact of the GRC on geological research was the result of the Gerace's support for a biennial geological research symposium. The first symposium was held in March 1982, and this past June the 14th biennial Symposium on the Geology of the Bahamas and Other Carbonate Regions was held at the GRC. As a result of that symposium series, and their published proceedings, hundreds of geologists have presented their work to colleagues, and hundreds of others have been exposed to the diverse and interesting research that has been conducted in the Bahamas and elsewhere.