Limit of Gray Limestone Aquifer, Southeastern Florida, USGS WRIR 99-4213

The lower Tamiami aquifer is mapped as being present in most of western and northeastern Hendry County, which are outside of the study area. However, the limestones of the Tamiami Formation, which are included in the lower Tamiami aquifer, thin to the north, and sand and sandstone layers make up most of the thickness of the formation in central Hendry County.

The easternmost extent of the gray limestone aquifer corresponds closely to the limits previously delineated by Fish (1988) and Fish and Stewart (1991). In northeastern Broward County, the eastern edge of the aquifer occurs at the transition from highly permeable limestone or contiguous shell sand to a significantly less permeable facies composed of sandy, clayey limestone and quartz sand and sandstone. In northeastern Miami-Dade County, the eastern limit of the aquifer is mapped where the aquifer merges with the Biscayne aquifer and the intervening semiconfining unit wedges out.