Tectonic evolution of the southeastern Caribbean in Cenozoic time
Oblique collision between the southern Lesser Antilles arc and continental South America controlled tectonics from end Eocene to present in the S.E. Caribbean. There, terranes are from N to S: 1. magmatic arc platform (Margarita to Grenadines); 2. forearc basin; 3. ophiolite belt that may be basement to the forearc basin; 4. accretionary prism whose structurally shallow rocks near Barbados may be equivalent to formerly deep-seated metasediments exposed in Tobago, Trinidad, Paria, and Araya; 5. foreland thrust belt in the slope and shelf cover of S. America; 6. E. Venezuelan-Trinidad foreland basin; and 7. S. American shield. The boundary between terranes 4 and 5 is probably a N-dipping thrust. Early in the Eocene, the southern L.A. arc was probably intra-Atlantic, NE-trending, and positioned offshore of the N-facing passive margin of northern S. America. The arc moved SE relative to S. America, first consuming Mesozoic oceanic lithosphere and accreting sediment of S. American provenance to its forearc, then riding obliquely over the slope and outer shelf of the continental passive margin. Major effects of the collision are uplift of deep-seated arc rocks, imbrication of arc elements, generation of the El Pilar tear fault, and foreland contraction and basining. The southern Lesser Antilles arc was not attached to a far traveled Caribbean plate of Pacific provenance. This implies the existence of boundaries within the Caribbean between an exotic Caribbean plate and the southern Antillean arc.
- Research Organization:
- Northwestern Univ., Evanston, IL (USA)
- OSTI ID:
- 6273806
- Report Number(s):
- CONF-8510489-
- Journal Information:
- Geol. Soc. Am., Abstr. Programs; (United States), Vol. 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cenozoic oblique collision of South American and Caribbean plates: New evidence in the Coastal Cordillera of Venezuela and Trinidad
Plate boundary forces in the vicinity of Trinidad-the-transition from transpression to transtension in the Southern Caribbean plate boundary zones
Related Subjects
CARIBBEAN SEA
GEOLOGIC HISTORY
PLATE TECTONICS
CENOZOIC ERA
CONTINENTAL CRUST
CONTINENTAL MARGIN
GEOLOGIC FAULTS
OCEANIC CRUST
ATLANTIC OCEAN
EARTH CRUST
GEOLOGIC AGES
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
SEAS
SURFACE WATERS
TECTONICS
580201* - Geophysics- Seismology & Tectonics- (1980-1989)