Geology and geophysics of the Bahamas
The broad, shallow banks and intervening deep water (800-4000 m) channels of the Bahama Platform are unlike any other topography on the larger Atlantic margin (Fig. 1). The Bahama Platform covers roughly an area of 470,000 km2, which is nearly equivalent to the area of the exposed Atlantic coastal plain from Cape Hatteras to Florida. The Bahama Platform is divided into a northwest part and a southeast part by a northeast trending line between Rum Cay bank and Oriente, Cuba (Fig. 1). The northwest part of the Platform is characterized by a larger portion of the area being shallow banks and a lesser portion being deep-water channels and basins with water depths of 800-4000 m. In contrast, the southeast portion of the Platform has a greater portion of the area as deep water channels surrounding smaller isolated banks; the depths of the channels are generally deeper than 2000 m. (Uchupi and others, 1971).
The deep channels and basins segmenting the Bahama Platform are of three different types: 1. open seaways with openings to deeper water at both ends; 2. closed seaways of linear proportions but open to deeper water only at one end; and 3. circular and semi-circular basins. Examples of open seaways are the Florida Straits, the Santaren/Nicholas Channels, the Northwest Providence Channel, the Northeast Providence Channel, and the Old Bahama Channel; Tongue of the Ocean (TOTO) and Exuma Sound are closed seaways; and Columbus Basin and Caicos Basin are semi-circular types.
Figures & Tables
The Atlantic Continental Margin
This synthesis covers stratigraphy, depositional processes, and geophysical interpretation of the major onshore and offshore marginal basins from Maine to the Bahamas, and includes an up-to-date review of thinking on regional tectonic history. Additional chapters discuss the theoretical aspects of thermal evolution, subsidence, and seismic stratigraphy as applied to this region. Geological resources including petroleum, water, sand and gravel, hard minerals, and heat flow are reviewed, and environmental hazards such as seismicity, coastal erosion, waste disposal and submarine instability as it relates to site of drilling platforms and mining are evaluated. A summary chapter reviews areas of controversy and suggests key topics for research.