Potassium-argon age determinations from the Central Inlier and the southern Blue Mountains of Jamaica are consistent with recent evaluations of the structural and stratigraphic relations among Cretaceous and Tertiary sequences exposed on the island. Cooling of the Ginger Ridge granodiorite stock in the eastern section of the Central Inlier in the Late Cretaceous (85 m.y.), metamorphism of the Blue Mountain schists (>76.5 m.y.), and dike intrusion (∼68.7 m.y.) mark important thermal and orogenic events during the Cretaceous in Jamaica. Radiogenic argon losses, resetting of metamorphic biotite retention ages in the Eocene (52 to 47 m.y.), and associated post-metamorphic intrusion of minor felsite bodies support other geologic evidence indicating regional uplift of fault-bounded Cretaceous blocks during the early Tertiary.