EN VI RON MENTAL GEOLOGIC ATLAS
OF COASTAL GEORGIA
GEOLOGIC ATLAS 5
Edited By Madeleine F. Kellam

RESEARCH GEOLOGISTS
Martha M. Griffin Vernon J. Henry Pau l F. Huddlestun Madele i ne F. Kellam Bruce J. O'Connor Mary Lynne Pa t e
Bruce a. Rado

PROJECT COORDINATORS
Martha M. Griffin, Madeleine F. Kel lam and Bruce a. Rado

RESEARCH ASSISTANTS
Thomas M. Loretto Denise McCarthy Lau ra M. Smith

PUBLICATION COORDINATORS
Elisandra S. Black Linda L. Stoutenburg

DEPARTMENT OF NATURAL RESOURCES
J. Leonard Ledbetter. Commissio ner
ENVIRONMENTAL PROTECTION DIVISION
Harold F. Rehe is, Assistan t Director
GEORGIA GEOLOGIC SURVEY
William H. Mclemore , State Geolo gis t

CARTOGRAPHERS
Madeleine F. Kellam L. Jeane Smith

Atlanta 1986
The Department of Iv'atural Resources is an equal opportunity employer and off'ers all persons the opportunity to compete and participa te in each area of Dl'>i'R employnwnt regardless of' race, color, religion, sex, national origin, age, handicap, or other non -merit fa ctorr>.

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TOPOGRAPHY AND BATHYMETRY

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EXPLANATION

30'

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Topographic contour - Shows land surface elevation in feet. Datum is National Geodetic Vertica l Datum of 1929. Contour interval 20 feet. Supple mentary contour (dashed) at 5 feet.
Bathymetric contour - Shows depth of wa ter in feet. Datum is mean low water. Contour interval 6 feet.

The relationship between the two datums is variab le. This map is not intended for navigational use.

31
oo

Plate No.
1

ENVIRONMENTAL GEOLOGIC ATLAS OF COASTAL GEORGIA

81 30'

81 00'

-\/',,

/
GEOMORPHOLOGy

Paul F. Huddlestun

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EXPLANATION
D Alluvial Deposits
Aeolian Sand Deposits Holocene Barrier Island Complex Silver Bluff Barrier Island Complex Holocene - Silver Bluff Back-Barrier Complex
D Princess Anne Barrier Island Complex D Princess Anne Back- Barrier Complex
Pamlico Barrier Island Complex Pamlico Back- Barrier Complex Talbot- Penholoway Barrier Island Complex

BARRIER ISLAND COMPLEXES OF GEORGIA'S COASTAL PLAIN

The coastal counties of Georgia contain numerous marine terraces, many of which contain low elongated ridges that parallel the present coastline. These ridges, and the flat terrain that separates them, are thought to be relic t barrier island and back-barrier complexes similar to those presently found along Georgia's coast. The ridges formed as barrier islands at relat ive sea level still-stands during the Pleistocene Epoch, when sea level worldwide was higher. Changes in mean sea level CM S L) throughout the Pleistocene created a series of barrier island complexes, now preserved as eroded ridges, which decrease in age with decreasing elevation. Most of the barrier islands of Georgia's present- day coast are composed of relict Pleistocene beach/dune deposits of the Silver Bluff complex, fronted by beach/dune deposits of the Recent, or Holocene, sea level rise.

AGE Holocene Pleistocene Pleistocene Pleistocene Pleistocene Pleistocene

COMPLEX Holocene Silver Bluff Princess Anne Pamlico Talbot Penholoway

BARRIER ISLAND ELEVATION average 10-20' above MSL ave rage 10-20 ' above MSL average 15-20' above MSL average 25-40' abo ve MSL average 55-75' above MSL average 75-95' above MSL

BACK-BARRIER ELEVATION average 0- 7' above MSL ave rage 0 -7' above MSL average 10-20' above MSL average 15-25' above MSL average 45-50' above MSL average 55-70' above MSL

Plate No.
2

ENVIRONMEN
v

EOLOGIC ATLAS OF COASTAL GEORGIA

81 30'

SOILS
Bruce Q. Rado

8 1 00'

TYBEE ISLAND

32

32

00'

00'

WASSAW ISLAND

OSSABAW ISLAND

ST. CATHERINES ISLAND

31
30.

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-,-_]

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31 00.

SAPELO ISLAND ST. SIMONS ISLAND JEKYLL ISLAND
CUMBERLAND ISLAND

31

EXPLANATION

30.

D Dominantly very gently sloping and gently sloping deep,
excessively drained to moderately well drained sandy soils on ridges and wet, loamy soils in depressions.
Q Seasonally wet soils that have a sandy or loamy surface
layer and loamy subsoils, on low ridges and wet loamy soils on broad flats and depressions.
c:J Dominantly wet soils that have a sandy or loamy surface
layer and loamy subsoil; on broad flats.

Wet soils that have a loamy surface lay er and clayey subsoil; in low-lying areas and depressions .
D Very poorly drained marshes that have clayey underlying
layers; along eastern seaboard and adjacent tidal streams.

Seasonally wet and wet alluvial soils that have predominantly loamy profiles throughout.

Dominantly very gently sloping to sloping well drained soils

that have a sandy or loamy surface layer and a loamy to

clayey subsoil, on side slopes, uplands, and broad interstream

31

divides.

00'

D Dominantly poorly drained soi ls that have a sandy surface
layer and a sandy to loamy subsoil; on large flat areas and
in depressions.

[J Level, poorly drained soils that have a loamy to peaty muck
sur face laye r and a peaty organic subsoil; in swamp lands and ponded areas.
D Nearly level, somewhat poorly drained and poorly drained
soils that have a predominantly sandy surface layer, and a loamy or clayey subsoil.

Plate No.
3

ENVIRON ME~

10

15 Miles

81 30'

EOLOGIC ATLAS OF COASTAL GEORGIA
81 00'

81 30 '

81 00'

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I
MINING AND MINERAL OCCURRENCES

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Bruce J. O'Connor

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Plate No.
4

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EXPLANATION

.SURFACE MINING OPERATIONS 1980 Sand - Active

31

30.

1:::,. Sand - Reclaimed

Fill - Active

~ Fill - Inactive

0 Fill - Reclaimed
Peat

EXPLORATION DRILL HOLES

Phosphate - One or more intervals
containing greater than 10% bone
phosphate of lime.

<8> Heavy Minerals - One or more inter-
vals containing greater than 1.5% heavy minerals.

MINERAL OCCURRENCES

Phosphate

Throughout the coastal area, phosphate bearing Miocene-age sediments are present in the subsurface.
- - - - - Western limit of concentrated phosphate deposits. Dashed where approximately located.
Southwest of this line phosphate occurs at depths greater than 200 feet.

Heavy Minerals

Throughout the coastal area, Pleistocene

and Holocene -age sediments contain

localized deposits of heavy minerals i.e.,

3 1

titanium, zirconium, and rare earth-bearing

00'

minerals, especially illmenite, rutile, zircon,

monazite. and xenotime.

Area of concentrated heavy mineral deposits.

81 00 '

POTENTIOMETRIC SURFACE OF THE PRINCIPAL ARTESIAN AQUIFER 1880- 1980
Madeleine F. Kellam

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1971

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1979

81'00

82'00

1980

81 00

EXPLANATION
Area where flow from artesian wells could have been obtained.
----50----
Potentiometric contour Shows altitude at which water level would have stood in tightly cased wells. Dashed where approximately located. Contour interval is 10 feet. Below -20 foot contour, contour interval is 20 feet. Datum is mean sea level.
0 5 10 15 20 MILES

The Principal Artesian Aquifer (PAA) is the major source of groundwater in Georgia.The aquifer is composed of Middle Eocene- to Miocene-aged limestone. In the coastal zone, the PAA is formed of several different permeable limestones, sepa rated by semi-confining units. The PAA is overlain by sandy clays and clays of Mi ocene age.The lower confining unit is a dense dolomitic limestone of Middle Eocene age.
Water enters the tilted strata of the aquifer in the recharge area in the upper Coastal Plain. The upper confining unit holds the water under pressure, so that the water will rise above the top of the aquifer 1n tightly cased wells which pene -

trate the PAA. Such wells are known as artesian wells. The height relative to mean sea level CMSL) to which the water in cased wells will rise is illustrated by the potentiometric maps above. When the potentiometric surface exceeds the elevation of the land surface, water in a cased well in the PAA will rise above the land surface. Such a well is known as a flowing artesian well.
Increased use of the PAA has caused a decline in the potentiometric level. For example, a 500 ft. deep well drilled into the PAA in Savannah in 1880 would have resuited in a flowing artesian well, for the water would rise 40ft. above MSL in a cased well. In 1980, the water in the same well would only rise to 130 ft. below MSL, mak-

ing it necessary to pump the water to the surface.
In some areas of heavy pumpage, such as Brunswick, the quality of water has deteriorated. Pumping has caused a lowering of hydrostatic head, known as a cone of depression, in the PAA. This has resulted in the infiltration of brackish water from lower strata into the aquifer. The potential for salt-water intrusion also exists in Savannah.
As use of the PAA increases, the area of artesian flow will continue to decrease. Although a large quantity of ground water is available from the PAA for future use, conservation of this vital natural resource must be practiced.

Plate No.
5

ENVIRONMENTAL GEOLOGIC ATLAS OF COASTAL GEORGIA

COASTAL PROCESSES
Martha M. Griffin

HOLOCENE

PLEISTOC ENE

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Retr eat of ice sheets causes sea level to rise: from approximately -190 to -70 ft. relative to today.

Maximum sealevel low stand probably occurred at this time .

Sea level approximately the same as current level.

Growth of continental glaciers initiates worldw i de lowering of sea level.

6 in,

4

2

0

1940

' 1950

:1960

1970

I I I I I I I I I I I I I I i1 I I I I I I I I i1 I I I I I I I I [ I

Curve showing recent sea-level rise recorded at Fort Pulaski, Georgia , On the east coast, a progressive rise in sea level has occurred since 1890. Mean sea-level curves indicate a rate of 0.09 inches per year for the period 1929-1971 . This gradual rise is the single most important long-term agent of shoreline retreat.

A. SEA LEVEL CHANGE
GEORGIA Vnr";',. ,-"'~
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~ FLA.

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10 Miles

SEA DIAGRAM EXPLANATION
Less th an :3ft. 3-5 ft 5-8 ft. 8-1 2 ft. Greater than 12 ft.
Refers to waves generated by lo cal winds blowing over the water. Bar le ngth shows yearly average percent of time that lo w, medium or high seas have come trom the given direction.

WIND DIAGRAM EXPLANATION
3-7 M.P.H, 8-12 M.P.H, Greater t han 12 M..P.H,

Bar length shows percerH of

time the wind blow s from each

c,<v

direction for each velocity.

Waves most often approach the shore from the south and southeast, but north and northeast waves have higher energy and a much greater impact upon the shoreline. High velocity winds most often approach shore from the northeast, producing tidal surges: hign waves and above normal water levels produce destructive forces along the shore. The winds of a "North easter" storm do not reach hurricane velocity, but they impact a larger area for a longer period of time.

D. WINDS AND SEAS - ST. SIMONS ISLAND

S.C.

1 TYBEE ISLAND
"' ' '
2

GEORGIA

OSSABAW ISLAND 3
ST. CATHE RINES ISLAND

4
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LITTLE ST. SIMONS ISLAND

5

tSea LeY.~,I

SEA ISLAND

30 Feet ',
7

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~ Mile~., FLA.

.0L---'--'10

CUMBERLAND ISLAND

Compare dreclged'"and undredged areas off Tybee ( 1) and Little St.

Simons (4) Islands, both deltaic islands. Extensive shoaling off Oss-

abaw (2) reflects its deltaic nature. Note steep gradients of profiles

1

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off eroding St. Catherines (3) and Sea (5) Islands. The shallow sand

sheet seaward of Jekyll (6) suggests Holocene landward migration.

The Cumberland (7) profile .shows historically stable Stafford Shoal.

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KY. TENN.
GA. ALA.

0

100 200 Miles

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3

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TIDAL RANGE

Variation of tidal range and wave energy along ,the Georgia Bight.

The effect of the regional embayment, which characterizes the south-

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'

eastern coast, is to magnify tidal range and minimize wave energy. The

Georgia coast has an average tidal fluctuation of ~pproximately 6 ft.

Spring ranges of 9 ft. are common. Wave heights of average be!ween 2.6

ft. and 4.1 ft.
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B. TIDAL RANGE
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OCEAN

Unaltered inlets are marked by well-developed ebb-tidal deltas, which are both sediment sources and sinks for adjacent barrier islands. Sand stored in the deltas is eventually transported sou thward to downdrift shorelines. Shoalinduced wave refraction produces a mechanism for onshore transport of stored sediment.
E. INLET DYNAMICS

WASSAW
SOU ND

EXPL ANA TION

ARMORED SHORELINE

JETTY

0

5 Miles

:-:;r

Because barrier islands are dynamic systems, any man-made changes in the coastal zone will modify the sediment budget. Jetties constructed in the late 1800's to facilitate navigation have these side effects: drastic alteration of the ebb-tidal delta, initially intensified deposition adjacent to the jetties, probable elimination of downdrift sediment transport, and development of a sediment sink seaward of the jetties. Protective shoreline structures can prevent the landward encroachment of the mean high water shoreline, but they generally accelerate the natural rate of erosion near the armored shoreline or along adjacent downdrift shorelines. Groins, built perpendicular to the shoreline. generally result in updrift accretion and downdrift erosion.

G. NEARSHORE BATHYMETRY

H. MAN-MADE FEATURES

Northern hemisphere hurricanes

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or,igin<tte in the tropics during

summer,: and fall accon'lrlanied by

,high )ides, heavi' ,rainfall, <;~nd,

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. winds exceeding -74 miles per

lj";, . .';::-:...' . -

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hour.

severe

strikes Georgia's coast once in

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every ten years. Hurricanes greatly influence shoreline sediment distributi0n

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patterns. Island modification occurs by, ero~ioh on the sea_ ward side and

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C. HURRICANE STRIKES

0 1 2 3 Miles ' L__.____,_ __J
Sapelo Island, Georgia illustrates distribution of Pleistocene and Holocene dune ridges and dominant longshore drift: note that the inlet shorelines are flood domin ated. During spring and summer, prevailing fair weather waves induce northward longshore transport of sediment. During fall and winter stonn waves induce southward transport. The net longshore drift is to the south due to the dominant northeast waves. Sediment reworking in the inlets is dependent on patterns and magnitudes of reversing tidal currents.
F. SEDIMENT TRANSPORT
The configuration of the Georgia coastline is controlled by sediment supply and the combination of wave and tidal regimes. The barrier islands of Georgia lie well within the extensive re gional embayment known as the Georgia Bight. Because tidal effects are magnified by this embayment, Georgia has the highest tides of the entire southern U. S. coast , averaging 6 to 10 feet. The coast of Georgia is tide dominated , as compared to wave-dominated coasts north and south of Georgia. To acco mmodate this large volume of water, the Georgia barrier island system is one of short, broad islands separated by deep tidal inlets.
A great quantity of sand is stored in extensive shoal systerns seaward of both the inlets and the central portions of the islands. These shoals absorb much of the wave energy of storm attacks and are thus directly linked to beach configuration.
The broad, shallow continental shelf adjoining Georgia so dampens wind and wave energy that wave heights are tvpically 9 to 12 inches, the lowest on the east coast of the United States. Because the strongest winds are from the northeast, waves strike the shore most forcefully from that direction, resulting in a net movement, or longshore transport of sand from north to south. Any interruption of this flow of sand results in a greatly altered shoreline and. frequently the expenditure of vast sums of money for corrective measures.
I. SUMMARY

Plate No.
6

ENVIRONMENTAL GEOLOGIC ATLAS OF COASTAL GEORGIA

81 30'

81 00'

SHORELINE
I \
Martha M. Griffin and Vernon J. H;sn{y

- 1982

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SAVANNAH HARBOUR PROJECT Project depth - 40 feet MLW

'

Average annual maintenance dredging

'"""~ Ogeechee River -, drainage area 109 mi 2

1965- 1977 was 7,157,571 yd 3

32

2--, average discharge 2358 tt 3/s
J

32

00'

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' 1 I ....... EXPLANATION
- - Mean high tide level

Net erosion 1924-1974

Relative stability 1924-1974

-(

------

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31

)

30.

' "---...

Altamaha River / drainage area 14,399 mi 2
average discharge 13,730tt3/s

D Net accretion 1924-1974

31

19 7 4 -1982 Characterized by overall continuation of erosion/

30'

accretion patterns established prior to 1974, with

some exceptions. New sites of shoreline recession ap-

peared on Cumberland Island south of the jetty and

along the St. Marys Entrance. Tybee Island showed

accretion on the northwestern portion, and Little Tybee

Island showed accretion on the northern portion. These

islands may show the effects of the Savannah Beach

renourishment project.

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1954/57-1974 Characterized by accelerating recession rates,
with a hurricane in 1964. New sites of shoreline erosion include central Wassaw Island. central Ossabaw Island. and northern Little Cumberland Island. Con tinued recession occurred on developed beaches of St. Catheri nes Island and the St. Simons 1 Little St. Simons 1 Sea Island system, offset by major accretion that occurred on Little St. Simons Island.

1924 -1954/5 7 Characterized by dynamic stability. A 1944 hur -

ricane showed only negligible long term effects. New

sites of shore line recession include north- central

BRUNSWICK HARBOUR PROJECT
Project depth -32 feet MLW
Average annual maintenance dredging 1960 - 1977 was 1,365,803 yd 3

Ossabaw Island, and north and north- central Jekyll Island. Net shoreline erosion occurred on Tybee Island 1 Little Tybee and on St. Catherines Islands. Northern Cumberland Island experienced erosion, but

deposition on the southern portion caused the island

to show a net advance. The St. Simons/ Little St. Si-

mons ;Sea Island system also shows net accretion

for this period, although erosion occurred on the cen-

tral strand of Sea Island and southwest St. Simons

00'

Island.

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~Satilla Rive r
drainage area 2790 mi 2
average discharge 2229 tt3/s

1857 -19 2 4 Characterized by shore! ine ace retion. Although
major hurricanes occurred in 1893, 1896, and 1898, the coast of Georgia prograded prior to 1924. Jekyll and St. Catherines Islands were the only islands which did not advance during this time. This period of overall deposition on the coast of Georgia may be due to the following: the 1890 sea level stand, lowest in 115 years; soil erosion which choked Piedmont rivers with sediment, increasing the supply to the coast; and the

\ -

St. Marys River

'--?.--~--'"' 1 drainage area 1180 mi 2

I ,-"'-average discharge 673 tt3/s

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Plate No.

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FL.

--

KINGS BAY PROJECT Project depth -36 feet MLW Average annual maintenance dredging 1955-1976 was 225,238 yd3
ST. MARYS ENTRANCE PROJECT Project depth -55 feet MLW Average annual maintenance dredging 1955- 1979 was 201,690 yd 3

fact that the Savannah River had not yet been impounded .

7

ENVIRONMENuY~AL GEOLOGIC ATLAS OF COASTAL GEORGIA

0

5

10

15 Miles

81 30'

81 00'

81 30 '

81 00'

LAND USE AND LAND COVER
Made l eine F. Kellam

3 2

32

0 0.

00'

Little Tybee Island .

Wassaw Is land

St. Catherines Island

3 1 30 '

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Blackbeard Island

31

EXPLANATION

30'

Sapelo Island
Little St. Simons Island

URBAN OR BUlL T-UP LAND
1 1-RESIDENTIAL, 12-COMMERCIAL, 13-INDUSTRIAL, 14- TRANSPORTATION , COMMUN ICATION , AND UTILITIES, 15-INDUSTRIAL AND COMMERCIAL COMPLEXES , 16- MIXED URBAN OR BUlL T-UP LAND, 17-0THER URBAN
OR BU l L T-UP LAND
lid AGRICULTURAL LAND
21-CROPLAND AND PASTURES, 23-CONF INED FEEDING OPERATIONS, 24-0THER AGRICULTURAL LAND

RANGELAND

St. Simons Island
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31-HERBACEOUS RANGELAND, 32-SHRUB AND BRUSH RANGELAND

Jekyll Is land

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[;) FOREST LAND
41-DECIDUOUS FOREST, 42-EVERGREEN FOREST LAND, 43-MIXED FOREST LAND

31 00'

D WATER

31 00 '

(\~//.,,L i ttle Cumberland Island

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51-STREAMS AND CANALS, 52-LAKES, 53-RESERVOIRS, 54-BAYS AND ESTUARIES
D WETLAND

61-FORESTED WETLAND , 62-NON-FORESTED WETLAND

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D BARREN LAND

Cumberland Island

72-BEACHES, 73-SANDY AREAS OTHER THAN BEACHES , 75-QUARRIES AND GRAVEL PITS, 76-TRANSITIONAL AREAS

Plate No .
8

EN V IRONME

EOLOGIC ATLAS OF COASTAL GEORGIA

81 30.

8 1 00'

\Y',,

/

COASTAL FLOOD HAZARDS

Mary Lynne Pate

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30'
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EXPLANATION

l>c "I Lowest lying areas at greatest risk of
flooding

D Areas where development coincides

with potential for flooding

31

D Developed areas

30.

The principal flood hazard along the coast of Georgia is due to hurricane-induced storm surges. A storm surge is a gradual rise in ocean water level. This rise is caused by the action of wind, and by the reduction of atmospheric pressure on the water surface at the storm's center. The destructive force of these surges is intensified by wind-induced waves.
On the average, Georgia's coast experiences a hurricane once in every 10 years. Georgia has been struck by a number of hurricanes in this century (see plate 6) although none of these are considered to be major hurricanes.
Flooding and destructive winds which accompany hurricanes pose a threat to both lives and property. A severe hurricane struck the Savannah area in 1893, resulting in 2000 fatalities. To reduce the potential for loss of life in the event of a severe storm, hurricane evacuation plans have been devised (see Hurricane Evacuation Plan for Coastal Georgia, Department of Defense, Civil Defense Division, 1981 ).
Low-lying coastal areas have the greatest potential for flooding. Because the majority of coastal land is low , high ground for development purposes is scarce. For this reason, many areas at risk of flooding have been developed. This map shows the lowest-lying coastal areas, which have the greatest potential for flooding, and their relative proximity to developed are as.
For more detailed information on flood hazard areas contact :
Floodplain Management Coordinator, Water Resources Branch, Department of Natural Resources

Plate No.
9

ENVIRON ME

0

5

10

15 Miles

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81 30'

EOLOGIC ATLAS OF COASTAL GEORGIA
81 00'

REFERENCES

PLATE

1. TOPOGRAPHY AND BATHYMETRY

4. MINING AND MINERAL OCCURRENCES

COASTAL PROCESSES (Cont'd.)

U.S. Department of Commerce , 1972. Storm evacuation map, Sava nnah: NOAA, NOS , No. T- 15020, scale 1:62,500.
_ ______ , 197 2. Storm ev ac uation map, Savannah Beach : NOAA, NOS, No. T-15021 , scale 1:62,500.
_______ , 1976. Storm evac uation map, Brunswick: NOAA, NOS, No. T-15070, scale 1:62,500.
, 1976. Storm evacuation map , Darien : NOAA, NOS, No . T-15068, scale 1:62,500.
, 1976. Storm evacuation map , Ludow ici: NOAA, NOS , No. T-15067 , scale 1:62,500.
_______ , 1976. Storm evacuation map, Woodbine : NOAA, NOS , No. T-1507 1, scale 1:6 2 , 5 0 0 .
_______ , 1977. Storm evacuation map , Fernandina Beach: NOAA, NOS, No. T-15071, scale 1:62,500.
___ _ ___ , 1980. Bathymetric map, Doboy Sound to Fernandina: NOAA, NOS, No. 11502, scale 1:80,000 .
U.S. Geological Survey, 1956 (rev . 1977). Topographic-bathymetric quadrangle, Brunswick , Georgia, scale 1:250,000 .
_ _____ , 195 7 (rev. 1966). Topographicbathymetric quadrangle, Jacksonville, Florida: Georgia, scale 1:250,000.

Darby, S.P., 1981. Personal communication. Surface Mined Land Reclamation Program, Macon , Ga .
Department of Natural Resources, 1982. Georgia surface mining and land reclamation activities : Environmental Protection Division , Surface Mined Land Reclama t ion Program, 38 p.
Georgia Geologic Survey, 1984 ( r eprint) . Min eral Resource Map, scale 1:500,000 .
Kline, S.W. and O'Connor, B.J., 1981. Mi n ing directory of Georgia: Georgia Geologic Survey Circ. 2., 18th ed . 49 p.
5. POTENTIOMETRIC SURFACE OF THE PRINCIPAL ARTESIAN AQUIFER 1880-1980
Krause , R.E. and Gregg, D.O ., 1972 . Water from the principal artesian aqu ifer in coa s ta l Ge o rgi a: Georgia Geologic Survey Hydrologic At las 1, 1 plate.
Krause , R.E. and Hayes, L .R., 1981 . Potentiometr ic surface of the principal artesian aquifer in Geor gia, May 1980: Georgia Geologic Survey Hydrologic Atlas 6 , Plate 1.
Mitchell, G.D., 1980. Potentiometric sur f ace of the principal artesian aqui f er in Georgia, November 1979: Georgia Geologic Survey Hydrologic Atlas 4, plate 1.

E. INLET DYNAMICS
Nash, G.J., Historical changes in the mean high water shoreline and nearshore bathymetry of south Georgia and north Florida: Univ. of Georgia, unpub . M.S. Thesis.
F. SEDIMENT TRANSPORT
Hoyt, J .H. and Henry, V.J ., 1967. Influence of island migration on barrier island sedimentation: G.S.A Bull., 78:77-86.
G. NEARSHORE BATHYMETRY
U.S. Department of Commerce, 1980. Bathymetric map, Doboy Sound to Fernandina: NOAA, NOS, No. 11502, scale 1:80,000.
U. S. Geological Survey, 1956 (rev. 1977). Topogr aphic-bathymetric quadr angle, Brunswick, Georgia , scale 1: 250,000 .
, 1957 (rev. 1977). Topographicbathymetric quadrangle, Jacksonville, Florida : Georgia, scale 1:250,000.
, 195 7 (rev. 197 8). Topograph icbathymetric quadrangle, Savannah, Georgia: South Carolina, scale 1:250,000.
H. MAN-MADE FEATURES
Griffin , M.M. and Henry , V.J ., 1984. Historical changes in the me a n high water shoreline of Georgia, 1857- 1982: Georgia Geologic Survey Bull. 98 , 96 p.

______ , 1957 (rev, 1978). Topographic bathymetric quadrangle, Savannah, Georgia: South Carolina, scale 1:250,000.

6 . COASTAL PROCESSES
A. SEA LEVEL CHANGE

2 . GEOMORPHOLOGY
Georgia Geologic Survey , 1976. Geologic map of Georgia, scale 1:500,000.
Huddlestun, P.F., in review . A revision of the lithostratigraphic units of the coastal plain of Geor gia : The Neogene: Georgia Geologic Survey Bull . 104.
3. SOILS
U.S . Department of Agriculture, 1961. Soil survey o f Mcintosh County, Georgia. Soil Conservation Service in cooperation with the University of Georgia, College of Agriculture, Agricultural Experiment Stations: U.S. Government Printing Office, 62 p.
_______ , 1974. So il survey of Bryan and Chatham Counties, Georgia. Soil Conservation Service in cooperation with the University of Georgia, College of Agriculture, Agricultural Experiment Stations: U.S. Government Printing Office, 71 p.
, 1980. Soil survey of Camden and Glynn Counties, Georgia . Soil Conservation Service in cooperation with the University of Georgia, College of Agriculture, Agricultural Experiment Stations: U.S. Government Printing Office, 81 p.
, 1982. Soil survey of Liberty and Long Counties, Georgia. Soil Conservation Service in cooperation with the University of Georgia, College of Agriculture , Agricultural Experiment Stations : U.S. Government Printing Office, 12 9 p.

Blackwelder, B.W., Pilkey, O.H., and Howard, J .D., 1979. Late Wisconsinan sea levels on the southeast U.S. Atlantic shelf based on in-place shoreline indicators : Science, v. 204, 4393 : 618-620.
Hicks , S.D., 1973. Trends and variability of yearly mean sea level, 1893-1971: NOAA Tech. Memo, NOS 12, 14 p.
B. TIDAL RANGE
Hubbard, O.K., Oertel, George, and Nummedal , Dag, 1979. The role of waves and tidal cur rents in the development of tidal inlet sedimentary structures and sand body geometry: Examples from N. Carolina, S. Carolina, and Georgia. Jour. of Sed . Petrology, 49(4): 1073-1092.
C. HURRICANE STRIKES
U.S. Army Corps of Engineers, 1970. Tybee Island, Georgia : beach erosion control and hurricane protection: Serial No. 63, Savannah, Georgia , 78 p.
U.S. Department of Comme r ce, 1979. North Atlantic hurricane tracking chart: National Weather Service.
D. WINDS AND SEAS
U.S. Army Corps of Engineers, 1970. Sea Island and St. Simons Island, Georg ia: beach erosion control and hurricane protection : Serial No. 61, Savannah, Georgia, 55 p.

7. SHORELINE DYNAMICS 1854-1982
Griffin, M.M . and Henry, V.J ., 1984. Historical changes in the mean high water shoreline of Georgia, 1857-1982: Georgia Geologic Survey Bull. 98, 96 p.
8. LAND USE AND LAND COVER
U.S. Geological Survey, 1976. Land use/land cover map, J acksonville, Florid a; Georgia, scale 1:250,000.
1976. Land use/land cover map, Savannah, Georgia; South Carolina, scale 1:250,000.
, 1977. Land use/land cover map, Brunswick, Georgia, scale 1:250,000.
9. COASTAL FLOOD HAZARDS
Federal Emergency Management Agency, 1982. Coastal residential construction workshop training session. Unpublished training manual.
U.S. Geological Survey, var ious dates, Floodprone area maps of Georgia, scale 1:24,000.
, 1976. Land use/land cover map, Jacksonville, Florida; Georgia, scale 1:250 ,000 . ___ _ __ _ , 1976. Land use/land cover map, Savannah, Georgia; South Carolina, scale 1:250,000. _______ , 1977. Land use/land cover map, Brunswick, Georgia, scale 1:250,000.

Plate No.
10

ENVIRONMENTAL GEOLOGIC ATLAS OF COASTAL GEORGIA