01 · Figure 2 / Plate 1
Key Wells and Cross Sections
Shows key wells, cluster sites, and cross-section lines used in PP1807. Popups include permanent links to DS760 borehole geophysical logs where matched.
Floridan aquifer system · published web maps
ArcGIS Maps
Explore the regional hydrogeologic framework across Florida and parts of Georgia, Alabama, and South Carolina—from key wells and cross sections to aquifer surfaces, thicknesses, and salinity interpretations.
These 26 ArcGIS Online maps and tools build on USGS Professional Paper 1807 and its associated digital data. Select a thumbnail or Open map to explore a map, or choose Description for its ArcGIS Online item overview. Maps and descriptions open in a new tab.
Download the complete ArcGIS Pro project or raster collection →
Freshwater/Saltwater Interface Estimator
Retrieve regional estimates of the 10,000 mg/L TDS surface elevation and depth, with explicit fresh-to-base and unavailable-data responses.
How it works, reusable popup code, and the public map →Showing 26 of 26 maps
02 · Figure 9
Generalized Geologic Map
Shows generalized regional geologic units and the approximate updip limits of the FAS and productive Upper Floridan aquifer.
03 · Figure 12
Closed Depressions and Major Springs
Shows closed-depression frequency in 25-square-mile grid cells and historical magnitude classes for major springs.
04 · Figure 20
Surficial-Deposit Thickness
Shows estimated thickness of surficial deposits using a classified raster, control points, contours, and regional aquifer areas.
05 · Figure 21 / Plate 3
Upper Confining Unit
Shows thickness and distribution of the upper confining unit using dense control points, contours, and regional confining-unit areas.
06 · Figure 22 / Plate 4
Top of the Floridan Aquifer System
Shows altitude of the top of the FAS using dense control points, contours, and geologic-unit context.
07 · Figure 28
Top of the OCAPLPZ and Head Difference
Shows altitude of the top of the Ocala–Avon Park lower permeability zone and interpreted head-gradient areas.
08 · Figure 30
Top of the Aggregated Avon Park Permeable Zone
Shows altitude and mapped extent of the aggregated APPZ, its limestone boundary, saline areas, control points, and contours.
09 · Figure 17
Top of the Upper Dolostone Unit
Shows altitude and interpreted extent of the upper dolostone unit using control points and contours.
10 · Figure 32
Upper Floridan Aquifer Thickness
Shows Upper Floridan aquifer thickness with component-unit regions, control points, contours, faults, and updip limits.
11 · Figure 33
Top of the Lisbon–Avon Park Composite Unit
Shows altitude of the top of the LISAPCU and its component areas using control points and contours.
12 · Figure 38
Top and Estimated Properties of the Middle Avon Park Composite Unit
Shows altitude, head-difference wells, and regional hydraulic-property classifications of the MAPCU.
13 · Figure 43
Top of the Bucatunna Clay Confining Unit
Shows altitude and regional extent of the Bucatunna clay confining unit with index and intermediate contours.
14 · Figure 44
Top of the Lower Floridan Aquifer
Shows altitude of the top of the Lower Floridan aquifer and regional hydrogeologic units that overlie it.
15 · Figure 46
Top of the Lower Avon Park Permeable Zone
Shows altitude and extent of the lower Avon Park permeable zone and estimated areas exceeding 10,000 mg/L TDS.
16 · Figure 45
First Permeable Zone Beneath LISAPCU/Bucatunna Clay
Shows altitude and extent of the first permeable zone beneath regional confining units and estimated areas exceeding 10,000 mg/L TDS.
17 · Figure 48
Top of the Glauconite Marker Unit
Shows altitude and interpreted regional confining character of the glauconite marker unit.
18 · Figure 19
Glauconite Marker Horizon
Shows altitude of the marker horizon with enrichment polygons depicting the extent and character of the underlying glauconite marker unit.
19 · Figure 49
Top of the Oldsmar Permeable Zone
Shows altitude of the OLDSPZ, Boulder Zone and Fernandina permeable-zone regions, and saline areas.
20 · Figure 24
Top of the Low-Resistivity Interval Below the OLDSPZ
Shows altitude of the low-resistivity interval beneath the OLDSPZ and estimated areas exceeding 10,000 mg/L TDS.
21 · Figure 23 / Plate 5
Base of the Floridan Aquifer System
Shows altitude of the FAS base and the geologic units that compose it, with control points, contours, faults, and updip limits.
22 · Figure 25 / Plate 6
Floridan Aquifer System Thickness
Shows full-system thickness and areas where the lower FAS is fresh to its base or exceeds 10,000 mg/L TDS.
23 · Kinnaman and Dixon, 2011
May 2010 Potentiometric Map
Shows the May–June 2010 Upper Floridan aquifer potentiometric surface, authoritative contours and wells, and head relative to the top of the FAS.
24 · PP1807 Figure 53 / DS926 Figure 54
Estimated 10,000 mg/L TDS Boundary
Shows the estimated regional position of the 10,000 mg/L total-dissolved-solids boundary in the FAS.
25 · PP1807 Figure 54 / DS926 Figure 55
Fresh- and Brackish-Water Zone Thickness
Shows a 12-class thickness raster, control points, and contours for the fresh- and brackish-water zones of the FAS.
26 · FAS — Freshwater/Saltwater Interface Estimator
Freshwater/Saltwater Interface Estimator
Click to retrieve the estimated 10,000 mg/L TDS surface elevation and depth, or identify fresh-to-base conditions. Includes a methods page and reusable Arcade popup code. Regional estimates on a 1,000-meter grid.
Source publications
- Williams, L.J., and Kuniansky, E.L., 2016. Revised hydrogeologic framework of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina (ver. 1.1, March 2016). USGS Professional Paper 1807, 140 p., 23 pls.
- Williams, L.J., and Dixon, J.F., 2015. Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system. USGS Data Series 926, 24 p.
- Williams, L.J., Raines, J.E., and Lanning, A.E., 2016. Geophysical log database for the Floridan aquifer system and southeastern Coastal Plain aquifer system (ver. 1.1, December 2016). USGS Data Series 760, 12 p.
- Kinnaman, S.L., and Dixon, J.F., 2011. Potentiometric surface of the Upper Floridan aquifer in Florida and parts of Georgia, South Carolina, and Alabama, May–June 2010. USGS Scientific Investigations Map 3182, 1 sheet.
Web-map adaptation and publication: LogicCloud Geo, Lester J. Williams. The maps are regional scientific interpretations intended for scientific, educational, and planning purposes; they are not intended for site-specific engineering, regulatory, or navigational use.