skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Cenozoic oblique collision of South American and Caribbean plates: New evidence in the Coastal Cordillera of Venezuela and Trinidad

Conference · · AAPG Bulletin (American Association of Petroleum Geologists); (United States)
OSTI ID:6063673
 [1];  [2];  [3]
  1. Northwestern Univ., Evanston, IL (United States)
  2. Carnegie Institute of Washington (United States)
  3. Ohio State Univ., Columbus (United States)

The hinterland of the Caribbean Mts. orogen in Trinidad and Venezuela contains schist and gneiss whole protoliths are wholly or partly of continental provenance. The hinterland lies between the foreland thrust belt and terranes. The terranes are alien to continental South America (SA) and may have proto-Caribbean or Caribbean plate origins. The hinterland rocks were widely thought to come from sediments and granitoids of Mesozoic protolithic ages and to be of Cretaceous metamorphic age. Such rocks are now know to be of at least two or more types, as follows: (1) low grade, protoliths of pre-Mesozoic basement and shelfal cover of uncertain age range, inboard locus, Oligocene to mid-Miocene metamorphic ages younging eastward (Caracas, Paria, and Northern Range belts), and (2) higher grade including high P/T, varies protoliths of uncertain age range, Cretaceous and ( )early Paleogene metamorphic ages (Tacagua, Araya, Margarita). The geometry, protoliths, structures, and metamorphic ages of type 1 parautochthoneity and an origin as a thickened wedge of crust-cored passive margin cover. The wedge grew by accretion between about 35 and 20 Ma during oblique transport toward the foreland. The diachroneity of metamorphism implies, as does the timing of foreland deformation, that the wedge evolved in a right-oblique collision between northern SA and terranes moving wholly or partly with the Caribbean plate since the Eocene. Type 2 rocks probably came with the terranes and are products of convergent zone tectonics, either in the proto-Caribbean plate. The hinterland boundaries are brittle thrusts that are out of sequence and imply progressive contraction from mid-Cenozoic to the present.

OSTI ID:
6063673
Report Number(s):
CONF-930306-; CODEN: AABUD2
Journal Information:
AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 77:2; Conference: International congress of the American Association of Petroleum Geologists (AAPG), Caracas (Venezuela), 14-17 Mar 1993; ISSN 0149-1423
Country of Publication:
United States
Language:
English

Similar Records

Tectonic evolution of the southeastern Caribbean in Cenozoic time
Conference · Tue Jan 01 00:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States) · OSTI ID:6063673

Tectonics and terranes of the Southeastern Caribbean
Conference · Mon Feb 01 00:00:00 EST 1993 · AAPG Bulletin (American Association of Petroleum Geologists); (United States) · OSTI ID:6063673

Late Cretaceous tectonics of the southern Sierra Nevada batholith (SNB) viewed from the Tehachapi Mountains (TM), California
Conference · Thu Apr 01 00:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States) · OSTI ID:6063673