Stable isotopic study of the groundwater of the Martha Brae River Basin, Jamaica

The hydrology of a small karst drainage basin in Jamaica, the Martha Brae River basin, was examined using stable isotopes. Variations in the isotopic composition of the groundwaters sampled and their positions relative to the local meteoric water line on a δD/δ 18 O diagram permitted the identification of two distinct groundwater types. The isotopic data also provided evidence that the most productive portion of the aquifer is divided by a major fault, which impedes groundwater flow. Information regarding the mechanisms and elevation of recharge was inferred from the δD versus δ 18 O relationships and differences in isotopic composition, respectively.