NEW MAPS OF GRAVIMETRIC ANOMALIES IN THE CARIBBEAN

Free-air anomaly maps and total Bouguer anomaly maps are presented for the Caribbean region, obtained from the gravimetric compilation published by the Scripps Institution of Oceanography, University of California, San Diego. The total Bouguer anomaly is calculated and atmospheric and Bullard B corrections are included to verify their importance in regional scale studies. Upon reviewing the statistical descriptors of the corrections and the calculated anomalies, no significant qualitative or quantitative contribution is observed. The corrections may therefore be discarded for regional scale studies. This map shows a wide range of anomalies, from -260 to 420mGal. In general, the minimum values are related to continental regions, while the maximum ones are associated to the oceanic crust (Atlantic Plate, oceanic crust of the Caribbean Plate, Yucatan Basin, Venezuelan Basin and the Cocos Plate). Negative anomalies stand out in Mexico, Central America, the North of South American plate and the Venezuelan Eastern Basin. The free air anomaly map displays an anomaly range from -360mGal to 590mGal. Some of the structures that are clearly represented by the anomalies of the vertical gradient are the Maracaibo, Eastern Venezuela, Grenada, Colombia and Venezuela basins, and the Ayes Ridge.