Back to Graduate Student Talks Along-strike Correlation of Seismic Sequences and Structures
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Collided Margin | Uncollided Lesser Antilles |
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Dutch Antilles ridge | Aves Ridge (remnant arc) |
Falcon-Bonaire basin | Grenada basin (back-arc basin) |
Blanquilla-Margarita platform | Lesser Antilles (volcanic arc) |
Cariaco-Carupano basin | Tobago trough |
Cordillera de la Costa-Serrania del Interior | Buried forearc region |
Maracaibo-Guarico-Maturin basins | Barbados accretionary prism |
In order to document along-strike continuity of terranes and their associated basins, I have used GIS to compile seismic lines and wells in the region. Sources include published and unpublished thesis studies, journal articles, and previously unpublished Gulfrex lines collected by Gulf Corporation in the early 1970s and donated to UTIG in 1984. Using these data I show a depth to basement map that documents the variation in sedimentary thickness along the strike of the major basins. I also use well data to provide control on the age of deformation in the basins. Main results of this study include:
Deformation of western basins is characterized by inversion of preexisting, basin parallel, normal faults probably created in the extensional Caribbean arc system, similar to the Lesser Antilles today.
Collapse and reorientation of the Caribbean arc terranes against the northern margin of South America has produced strike-slip faulting and strike-slip related basin formation along the EW-oriented terrane boundaries.
Oblique collision has produced lateral ramp faults oriented in a NW-SE direction. These faults disrupt the lateral continuity of basins and terranes, subdivide deep and shallow water areas, and act as pathways for sediments to pass across-strike from shallow to deep water areas.