A bimodal distribution of zircons consisting of rounded, variably radiation damaged grains and clear, euhedral grains is present in the sandstones of the Scotland Formation, part of an accretionary prism exposed in northeastern Barbados. Fission track dating of detrital zircons indicates the presence of a component with ages ranging from 20 to 100 Ma with a strong grouping between 20 to 50 Ma. Results indicate that the Scotland Fm. , previously dated by paleontologic methods as Eocene, may actually be as young as late Oligocene. **4**0Ar/**3**9Ar age spectrum analysis of detrital feldspars from the Scotland formation provides additional evidence of a cratonic source for these sediments. Results from this study, together with paleogeographic constraints, suggest that the source area for these sediments was an area of the Guyana Shield which was drained by the proto-Orinoco river and deposited in a submarine fan north of the Unare depression.
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