Estudio Geofísico De La Cuenca De Grenada

The results of a combined gravimetric-magnetic study of the Grenada Basin are presented. Two domains migth<br>be recognized based on the map patterns of the anomalies in the area. South of parallel 15.5° regional gravity<br>shows a steep and steady gradient, presumably associated to the development of a relatively thick sedimentary<br>basin. Modeling of a gravimetric profile suggests that the thickness of the crust varies from a maximun of<br>about 25 km under the Aves Ridge, to less than 8km beneath the Grenada Basin, where it might be covered by<br>as much as 7 km od sediments. This architecture is interpreted as a result of the development of the Grenada<br>Basin in an extensional back-arc setting. Furthermore, the high frequency magnetic anomalies along the profile<br>have been successfully matched using a madel where the uppermost oceanic crust was divided into alternately<br>normally and reversely magnetized blocks. The fact that no major uplift or ridge trace is actually present in the<br>basin is regarded as a result of thermal subsidence enhanced by sediment loading postdating the sea floor<br>spreading event.<br>The second domain, north of parallel 15,5°, is characterized by high frequency residuals probably indicating a<br>shallow and strongly faulted basement.