223 D27. Structural Geology & Tectonics III

Thursday, 29 October 2020
5:30 PM - 8:00 PM
Meeting Rooms

CENOZOIC EVOLUTION OF THE NORTHERN CARIBBEAN PLATE BOUNDARY: INSIGHTS FROM THERMOCHRONOMETRIC, KINEMATIC AND GEOMORPHIC DATA

Paper number: 223-9
Program: Technical Sessions
Time: 7:10 PM – 7:20 PM

Authors

Abstract

It is widely accepted that the Northern Caribbean plate boundary transitioned from compressional to transcurrent deformation in the Paleogene in response to collision with the Bahamas platform and accompanied by an eastward shift of the locus of subduction. However, the temporal and along-strike spatial onset of this transition, from Cuba to Puerto Rico, remain poorly constrained. The deformational and magmatic history of the island of Hispaniola is key to understanding the plate boundary kinematic transition in the early Eocene (~50 Ma). However, Hispaniola lacks critical constraints on the timing of deformation and exhumation. This study presents new data from zircon and apatite (U-Th)/He analyses from central Hispaniola in the Dominican Republic and constrains the exhumation history of tonalitic plutons in the Cordillera Central. These data are combined with >500 U-series, noble gas, and fission-track compiled ages from across the Greater Antilles to elucidate the locus and timing of this plate-boundary reorganization. We integrate these data with geological and structural field observations and measurements of kinematic indicators, as well as a geomorphic analysis of tectonically influenced channel steepness and concavity, and knickpoint migration in the Cordillera Central and Cordillera Septentrional. These data provide critical new insights into the timing and kinematics of plate-boundary deformation in Hispaniola and their connection to exhumation along faults bounding the Cordilleras, and at the broader scale, the timing of plate reorganization within the geodynamic framework of the Northern Caribbean Plate Boundary.

Geological Society of America Abstracts with Programs. Vol. 52, No. 6

doi: 10.1130/abs/2020AM-353996

© Copyright 2020 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.