This dataset comprises a vector shapefile of the Puerto Rico geologic map from Bawiec et al. (1999), clipped to study areas in the Lares, Utuado, and Naranjito municipalities, with a modified basal contact of the Tertiary Lares Limestone (Tla) re-mapped using a lidar-derived digital elevation model (DEM) (USGS, 2018). The limestone unit of interest forms a prominent break in slope with the underlying geologic units, and this break in slope was mapped as the Tla basal contact. Only the southern contact of the Tla unit was modified. References: Bawiec, W.J., ed., 1999, Geology, geochemistry, geophysics, mineral occurrences and mineral resource assessment for the Commonwealth of Puerto Rico: U.S. Geological Survey Open-File Report 98-038, available online only. U.S. Geological Survey, 2018, USGS Lidar Point Cloud PR Puerto Rico 2015, accessed October, 2018 at URL https://nationalmap.gov/3DEP/