Thermal evolution of the eastern Serrania del Interior foreland fold and thrust belt, northeastern Venezuela, based on apatite fission track analyses

[摘要] Apatite fission track data show a gradual decrease in age (∼30 Ma to ∼15 Ma) from north to the south in the eastern SerranIa del Interior, northeastern Venezuela. Based on a previous study, a model for the tectonic evolution of the eastern SerranIa is proposed in which two stages of deformation occurred. Stage 1 (45 Ma--20 Ma) involves the internal deformation of fault blocks. Stage 2 (20 Ma--12 Ma) involves envelopment thrusting, doubling the thickness of the thrust sheet. Shortening within the SerranIa del Interior ceased at 12 Ma. In stage 1, cooling and exhumation rates were 5.8°C/km and 0.26 km/my, respectively, and in stage 2, cooling and exhumation rates were 4.25°C/km and 0.2 km/my, respectively. The deformation of the SerranIa prior to the collision of the Caribbean plate with South America is probably related to the convergence of the North and South American plates.

[发布机构] Rice University