The Neogene stratigraphy of the Azua and Enriquillo basins of south-central Hispaniola (Dominican Republic) records the uplift history of central Hispaniola. The marine sequences change upward from deep-marine pelagic strata of the Sombrerito Formation to coastal clastic rocks of the Arroyo Blanco and Las Salinas Formations. A 2,000-m-thick southeastward-prograding turbidite sequence, the Trinchera Formation, reflects infilling of the Azua Basin. A transition from finer grained outer fan-type facies to coarser grained inner fan-type facies is evident in measured sections.

Planktonic foraminiferal and ostracode evidence indicates that the marine section of the Azua basin extends from lower to upper Miocene in its northwestern part and from middle Miocene to lower Pliocene in its southern part. The shallow-marine and lagoonal section of the Enriquillo basin extends from the lower Pliocene upward. Benthic foraminiferal paleobathymetry from the Azua basin is consistent with lithofacies data and indicates shoaling from depths near the lower-middle bathyal boundary to marginal-marine depths.

The Azua and Enriquillo basins evolved in two stages: a tectonically quiet open ocean stage before the late Miocene; and a tectonically active, laterally constrained clastic basin stage from the late Miocene to the present. The second stage records rapid uplift and erosion of the Cordillera Central of central Hispaniola and the formation of northwest west-northwest-striking ramp basins in south-central Hispaniola.