Plate boundary readjustment in oblique convergence: Example of the Neogene of Hispaniola, Greater Antilles

Abstract

The Haitian fold‐and‐thrust belt is the major mountain belt of Haiti (western part of Hispaniola, Greater Antilles) and resembles a compressive restraining bend between the two major faults which have driven the opening of the Cayman Basin since the Eocene. During the rifting stage, from the middle to the late Eocene, this area underwent an extensional evolution with fissural volcanic activity along NE‐SW tilted blocks. The Haitian fold‐and‐thrust belt was constructed from the Early Miocene until the Present by stacking sedimentary units into a collisional wedge perpendicular to the tilted blocks, which was propagating to the southwest. During the construction of the wedge, piggyback basins were formed and progressively uplifted. During the late Neogene, convergence is localized in the Cul‐de‐Sac‐Enriquillo trough where the active front proceeds southward onto the Beata ridge. In this area, Miocene to Quaternary wrench structures of the lower plate, like the Southern Peninsula and the Enriquillo‐Plantain Garden faults, are reactivated as normal faults, owing to the loading of the fold‐and‐thrust belt.