Lower Quintuco carbonates are comprised of: (1) oolitic grainstones, (2) burrowed, dolomitized oolite-skeletal-peloid packstones/ wackestones, (3) dolomudstones and bedded anhydrites, and (4) very fine-grained, superficially coated oolite grainstones. These sediments are commonly packaged into shoaling- and coarsening-upward parasequences.

Reservoir-quality porosity and permeability exist almost exclusively in burrowed, dolomitized packstones and wackestones. These strata are interpreted as off-bar facies deposited on the landward side of bar complexes, similar to modern facies analogs known in the Joulters Cay area of the Bahamas. In the lower Quintuco Formation, dolomite preferentially replaced carbonate mud. Below an inferred widespread paleo-exposure surface, ooid-skeletal-peloid grains were then dissolved to leave an open pore network with abundant moldic and intercrystalline porosity.