Keywords
Maurice Ewing Bank
density modeling
tectonosphere
Section
Abstract
The Falkland Plateau and Maurice Ewing Bank are located in the southern part of the Atlantic Ocean near the South America continental margin. The tectonic origin and lithosphere structure of this territory remain controversial so far. To study the tectonosphere of these structures, gravity field anomalies in Bouguer reduction and in free air reduction were analyzed. Density modeling along three latitudinal profiles was also performed. Data from open sources including seafloor topography, free-air and Bouguer-corrected gravity field anomalies, ocean floor age, sediment thickness data, and seismic tomography were used. Two-dimensional density modeling showed that underwater prominence near the South America continental margin includes crust blocks of different genesis: the Falkland Plateau is composed of continental crust, the Maurice Ewing Bank represents a fragmented block of continental crust penetrated by intrusions, and the basin underlying the Falkland Plateau may be underlain by oceanic crust.
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