Cenozoic Tectonic and Sedimentary Development of the North American-Caribbean Transform Boundary: ABSTRACT

Abstract

The North American-Caribbean plate boundary consists of strike-slip deformation extending 3,200 km from the Middle American volcanic arc in western Guatemala to the northern Lesser Antilles. The authors have reconstructed the complex sedimentary and tectonic evolution of this zone over the past 65 m.y. by integration of onshore geologic data and offshore geophysical data. Onshore geologic data consists mainly of detailed structural maps and biostratigraphic studies from uplifted sedimentary basins in Hispaniola and Jamaica. Offshore data consists of single and multichannel seismic profiles and side-scan sonar maps. Both onshore and offshore data have been synthesized into a set of computer-based, paleogeographic maps for the following Cenozoic periods: late Paleocene, middle Eocene, late Oligocene, early Miocene, late Miocene, Pliocene, and Holocene. These data allow them to generalize the tectonic evolution of the boundary into three stages. Stage 1: Paleocene to early Eocene rifting and bimodal volcanism associated with formation of the Cayman Trough pullapart basin. Nonmarine to shallow marine sedimentation was controlled by northwest-northeast-striking normal faults formed at a high angle to the direction of plate motion. Stage 2: middle Eocene to early Miocene strike-slip faulting across a broad, California Borderlands-type margin. Shallow marine to marine sedimentation was controlled by strike-slipmore » faults parallel or at a low angle to the direction of plate motion. Stage 3: middle Miocene to present strike-slip faulting along a single major fault. Deep-marine sedimentation was controlled by a major strike-slip fault scarp formed approximately parallel to the direction of plate motion over most of the length of the boundary. Eustatic sea level effects are recognizable in all three stages.« less