USGS - science for a changing world

Georgia Water Science Center

  home   information/data   projects   publications   GWIN   RiverCam   drought   flood   about   contact

PUBLICATIONS

ABOUT THE GEORGIA
WSC

USGS IN YOUR STATE

USGS Water Science Centers are located in each state.

There is a USGS Water Science Center office in each State. Washington Oregon California Idaho Nevada Montana Wyoming Utah Colorado Arizona New Mexico North Dakota South Dakota Nebraska Kansas Oklahoma Texas Minnesota Iowa Missouri Arkansas Louisiana Wisconsin Illinois Mississippi Michigan Indiana Ohio Kentucky Tennessee Alabama Pennsylvania West Virginia Georgia Florida Caribbean Alaska Hawaii New York Vermont New Hampshire Maine Massachusetts South Carolina North Carolina Rhode Island Virginia Connecticut New Jersey Maryland-Delaware-D.C.

Georgia Water Science Center Publications

Hydraulic Properties of the Floridan Aquifer System and Equivalent Clastic Units in Coastal Georgia and Adjacent Parts of South Carolina and Florida

Georgia Geologic Survey Information Circular 109, 50 pages (Published August 2004)

John S. Clarke, David C. Leeth, DáVette Taylor-Harris, Jaime A. Painter, and James L. Labowski

ABSTRACT

Cover photograph: Ship in Savannah Harbor, Georgia, 2001. Photograph by: Ed Martin.Hydraulic-property data for the Floridan aquifer system and equivalent clastic sediments in a 67-county area of coastal Georgia and adjacent parts of South Carolina and Florida were evaluated to provide data necessary for development of ground-water flow and solute-transport models. Data include transmissivity at 324 wells, storage coefficient at 115 wells, and vertical hydraulic conductivity of 72 core samples from 27 sites.

Hydraulic properties of the Upper Floridan aquifer vary greatly in the study area due to the heterogeneity (and locally to anisotropy) of the aquifer and to variations in the degree of confinement provided by confining units. Prominent structural features in the area—the Southeast Georgia Embayment, the Beaufort Arch, and the Gulf Trough—influence the thickness and hydraulic properties of the sediments comprising the Floridan aquifer system. Transmissivity of the Upper Floridan aquifer and equivalent updip units was compiled for 239 wells and ranges from 530 feet squared per day (ft2/d) at Beaufort County, South Carolina, to 600,000 ft2/d in Coffee County, Georgia. In carbonate rock settings of the lower Coastal Plain, transmissivity of the Upper Floridan aquifer generally is greater than 20,000 ft2/d, with values exceeding 100,000 ft2/d in the southeastern and southwestern parts of the study area (generally coinciding with the area of greatest aquifer thickness). Transmissivity of the Upper Floridan aquifer generally is less than 10,000 ft2/d in and near the upper Coastal Plain, where the aquifer is thin and consists largely of clastic sediments, and in the vicinity of the Gulf Trough, where the aquifer consists of low permeability rocks and sediments. Large variability in the range of transmissivity in Camden and Glynn Counties, Georgia, and Nassau County, Florida, demonstrates the anisotropic distribution of hydraulic properties that may result from fractures or solution openings in the carbonate rocks. Storage coefficient of the Upper Floridan aquifer was compiled for 106 wells and ranges from about 0.00004 at Beaufort County, South Carolina, to 0.04 in Baker County, Florida.

Transmissivity of the Lower Floridan aquifer and equivalent updip clastic units was compiled for 53 wells and ranges from about 170 ft2/d in Barnwell County, South Carolina, to about 43,000 ft2/d in Camden County, Georgia. Transmissivity of the Lower Floridan aquifer is greatest where the aquifer is thickest—in southeastern Georgia and northeastern Florida—where estimates are greater than 10,000 ft2/d; at one well in southeastern Georgia transmissivity was estimated to be as high as 200,000 ft2/d. Storage-coefficient data for the Lower Floridan aquifer are limited to three estimates in Barnwell and Allendale Counties, South Carolina, and to estimates determined from six multi-aquifer tests in Duval County, Florida. In the South Carolina tests, storage coefficient ranges from 0.0003 to 0.0004; this range is indicative of a confined aquifer. The storage coefficient for the combined Upper and Lower Floridan wells in Duval County, Florida, ranges from 0.00002 to 0.02.

Vertical hydraulic conductivity was compiled from core samples collected at 27 sites. For the Upper Floridan confining unit, values from 39 core samples at 17 sites range from 0.0002 to 3 feet per day (ft/d). For the Lower Floridan confining unit, values from 10 core samples at 9 sites range from about 0.000004 to 0.16 ft/d. Vertical hydraulic conductivity of the Upper Floridan aquifer was compiled from 16 core samples at five sites, mostly in the Brunswick, Georgia, area and values range from 0.00134 to 160.4 ft/d. Vertical hydraulic conductivity for the semiconfining unit separating the upper and lower water-bearing zones of the Upper Floridan at Brunswick, Georgia, compiled from 6 core samples at three sites ranges from 0.000008 to 0.000134 ft/d. The vertical hydraulic conductivity of the Lower Floridan aquifer in a core sample from a well at Brunswick, Georgia, is 5.3 ft/d; this value is comparable to values for the Upper Floridan aquifer.

TABLE OF CONTENTS

Abstract

Introduction

Purpose and scope

Description of Study Area

Well-Identification Systems

Previous Studies

Acknowledgments

Hydrogeology

Geologic Setting

Floridan Aquifer System

Hydrologic-Property Data

Transmissivity and Storage Coefficient

Vertical Hydraulic Conductivity

Aquifer-Test Data Qualifiers

Hydraulic Properties of the Floridan Aquifer System

Upper Floridan Aquifer and Equivalent Clastic Units

Lower Floridan Aquifer and Equivalent Clastic Units

Vertical Hydraulic Conductivity

Summary

Selected References

Appendix A


Download the PDF file (2 Mb). This report (2 Mb) is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.

The full report can be ordered from the Georgia Geologic Survey. You may order online, or call or write:

Georgia Geologic Survey
19 M. L. King Jr. Drive, S.W.
Room 400, Maps and Publications
Atlanta, GA 30334
Telephone: (404) 656-3214

USGS Home Water Climate Change Core Science Ecosystems Energy and Minerals Env. Health Hazards

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://ga.water.usgs.gov/publications/other/ggs-ic109/index.html
Page Contact Information: webmaster-ga@usgs.gov
Page Last Modified: Tuesday, 04-Feb-2014 08:22:48 EST