MAP SERIES NO. 129

MINERAL RESOURCES OF

JEFFERSON COUNTY, FLORIDA

BY


PAULETTE BOND, P.G.#182, RONALD W. HOENSTINE
AND ED LANE




FLORIDA GEOLOGICAL SURVEY
DIVISION OF RESOURCE MANAGEMENT
DEPARTMENT OF NATURAL RESOURCES


TALLAHASSEE, FLORIDA
1989
ISSN 0085-0624

JEFFERSON COUNTY

INTRODUCTION

In recent years, Florida's population has increased dramatically. This population growth
has been accompanied by extensive douelopmnt. Development, by its very nature, may
render important mineral resources inaccessible to mining even though those resources
are essential to the various activities that accompany growth. The industries associated with
the utilization of mineral resources have a positive impact on Florida's economy. Extraction,
transportation and distribution of mineral resources generate employment for the state's
citizens and are a source of revenue for state and local government.
Utilization and conservation of mineral resources may be in conflict with the goals and
projects that arise from rapid population growth. In 1985 and 1986, the Florida Legislature
enacted legislation which requires each county to establish a comprehensive land use plan
with certain deadlines. These land use plans should serve to reconcile the pressures of
population growth with wise utilization of essential mineral resources. The information
provided here may also be applied to problems involving zoning, road construction and
waste disposal site location.
As a response to this act and at the request of the Apalachee Planning Council, the
Florida Geological Survey initiated a study of the mineral resources of Jefferson County.
The results of the study are presented as a map with an accompanying text written for use
by state and local planners.
At present there is no commercial production of mineral commodities In Jefferson
County. The general assessment of mineral resource potential presented here is not site
specific.
Resource evaluation for this report is based on a number of sources including Florida
Geological Survey reports and unpublished data, field reconnaissance, state and federal
statistical data, and state and federal officials. The diversity of sources as well as their close
association with the various aspects of resource evaluation lend substantial confidence to
the general assessments and inferences of this report.
METRIC CONVERSION FACTORS

in order to prevent the awkward duplication of English and metric units in this report the
following conversion factors are provided.

MULTIPLY BY TO OBTAIN

feet 0.3048 meters
mies 1.609 kilometers

GEOMORPHOLOGY

White, Vernon and Purl (in Purl and Vernon, 1964) divided the state into a number of
general regions. Jefferson County includes three of these regions: the Northern Highlands,
the Gulf Coastal Lowlands and the Coastal Swamps. Calico Hill, a minor feature
superimposed on the Gulf Coastal Lowlands of Jefferson County is mapped by White,
Vernon and Purl (in Puri and Vernon, 1964) but is not discussed In their work. Yon (1966)
completed a detailed study of Jefferson County in which he described landforms which are
locally superimposed on the regionally extensive features proposed by White, Purl and
Vernon.
The Cody Escarpment separates the Northern Highlands from the Gulf Coastal Lowlands
in Jefferson County (Figure 1). The Northern Highlands is a series of gently sloping, well
drained plateaus which have been dissected by dendritic streams. This geomorphic region
extends north into Georgia and Alabama. The Cody Escarpment, which is considered to be
one of the most persistent topographic breaks in Florida, extends east from the
Apalachicola River Valley to central Putnam County and is locally breached by the valleys of
major streams.
The Northern Highlands have been locally subdivided; in the region that includes
Jefferson County they are represented by the Tallahassee Hills. The Tallahassee Hills have
been extensively dissected by stream erosion and subsurface dissolution of underlying
limestone (Yon, 1966). They are characterized by relief ranging from less than 50 feet to
approximately 100 feet with elevations locally of approximately 160 feet above mean sea
level (MSL). In Jefferson County, the Tallahassee Hills are characteristically interspersed
with lakes, ponds and numerous small streams. The Tallahassee Hills of eastern Jefferson
County in the vicinity of the Aucila River are characterized by numerous wetland areas. Hills
in this area are isolated and relief is somewhat lower than relief noted in westem Jefferson
County (Yon, 1966). The area of Jefferson County, which is characterized by the
Tallahassee Hills, is underlain mainly by the Pliocene Series (COSUNA chart, Gulf Coast
Section, Braunstein et al., 1988), Miccosukee Formation (Hendry and Yon, 1967).
The Gulf Coastal Lowlands are bounded to the north in Jefferson County by the Cody
Escarpment. They are low in elevation, poorly drained and extend south to the Gulf of
Mexico. In Jefferson County, this geomorphic region is occupied by the extension of the
Woodville Karat Plain from Leon and Wakulla Counties (Yon, 1966) (Figure 1). The
Woodvile Karst Plain (Hendry and Sproul, 1966) is a low, gently sloping plain characterized
by dune sands lying on a limestone surface. The porous dune sands have allowed water to
percolate downward, causing dissolution in underlying limestones. Collapse of these
limestones has resulted In the development of shallow sinkholes (Yon, 1966).
The coastline is marshy and Irregular without sand beaches or barrier slelands. It is placed
Into the Coastal Swamps region by White, Puri and Vernon (Puri and Vernon, 1964). The
absence of beaches and barriers is due to the shallow offshore slope which results in a lack
of wave actMty and an Insufficlent sand supply.
Virtually all of the valleys in Jefferson County are associated with rivers which flow
through the county and may be classified as river valley lowlands (Yon, 1966). Although a
number of streams originate in Jefferson County or (low through it the three major ones are
the Auclla. Waciesa and St Marks Rivers (Mineral Resources Map).
Healy (1975) mapped four marine terraces In the Tallahassee Hils of Jefferson County
(Figure 2). These terraces Include the Haziehurst Terrace (215-320 feet MSL), the Coharie
Terrace (170-215 feet MSL), the Sundedand Terrace (100-170 feet MSL), and the Wicomico
Tenace (70-100 feet MSL) (Figure 2). Healy mapped these four terraces in Jefferson County
on theastes of contour elevations and topographic expression of land forms. A morede-
taled study (Yon. 19),. which considered bedrock and cowering sediments in addition to
topographic elevaons and rlxpreselon, did not recognize marine terraces In the Tallahassee
His of Jefferson County. Thus, the Hazlehurat, Cohade, and Sunderland Terraces probably


represent elevation zones, as opposed to true marine terraces and will not be discussed
further In this report.
The three marine terraces superimposed on the Gulf Coastal Lowlands of Jefferson
County are discussed by Yon (1966) and Healy (1975), who also provide summaries of the
historical development of the terrace nomenclature pertinent to Jefferson County.
Reference should be made to those publications for additional Information.
The Wicomico Terrace (70-100 feet MSL) in Jefferson County (Yon, 1966) is bounded to
the north by the Cody Scarp and includes the area between the northern bounding scarp of
the Pamlico Terrace and the Cody Scarp. Healy (1975) extends this terrace Into the
Northern Highlands based on elevation. Sediments associated with the Wicomico Terrace.
include sand and clayey sand which are deposited almost entirely on Suwennee Limestone
(Yon, 1968).
The Pamlico Terrace in Jefferson County extends from the 10-foot contour (the elevation
of the base of the small scarp which marks the landward limit of the Silver Bluff Terrace)
inland approximately eight miles (Yon, 1966). The northern boundary of the Pamlico
Terrace in Jefferson County is marked by a scarp, which has Its toe at an elevation ranging
from 26 to 30 feet, and exhibits eight to ten feet of relief. The Pamlico Terrace in Jefferson
County is a limestone plain which is covered by varying thicknesses of sand and clay. The
surface is well drained in eastern Jefferson County but is poorly drained with swamp
development to the west (Yon, 1966). Calico Hill is described by Yon (1966) as a sand ridge
with approximately 12 feet of relief oriented parallel to the Wacissa River and may represent
a Pamnlico dune.
The Silver Bluff Terrace, the youngest and lowest coastal terrace, extends from the coast
to the 10-foot contour line which marks the base of the small scarp (Yon, 1966). Adjacent to
the present coastline the Silver Bluff Terrace is characterized by coastal marshlands
developed on the underlying Suwannee Limestone.
GEOLOGY

The rocks and sediments that underlie Jefferson County range in age from Mesozoic to
Recent. To date, the deepest penetration of subsurface sediments in the county occurred at
a depth of 7,909 feet (MSL). These sediments, obtained from an oil well (W-1854, section 1,
Township 2S, Range 3E), were identified as Triassic (?) diabase and related igneous rocks
deposited approximately 210 million years ago (Applin, 1951; Arthur, 1988).
Thousands of feet of Mesozoic Era siliciclastics and carbonates limestones and
dolomites) are overlain by carbonates and near-surface sillciclastic sediments Including
sand, silt, and clay that were deposited during the Cenozoic Era. Figure 3a shows the
location of shallow geologic cross sections used In this report.
The oldest exposed unit In Jefferson County is the Suwennee ULimestone, deposited 24 to
37 million years before present (B.P.), during the Ollgocene Epoch. It crops out extensively
(although locally covered by a veneer of Pleistocene sands) south of Wacissa in southern
Jefferson County (Yon, 1966) and limited data suggests its thickness ranges from 150 180
feet (Figure 3b). Uthologically It is a pale orange, finely crystalline, fossliferous limestone.
Locally, the Suwannee Umestone may be silicifled or dolomitized (Yon, 1966).
The Miocene age St Marks Formation lies above the Suwannee Limestone in much of
Jefferson County, although locally it is absent (Yon, 1966). In Jefferson County, it is a white
to very pale orange, finely crystalline, sandy, slty, clayey limestone. Its major outcrop areas
occur in southern Jefferson County. The St. Marks Formation may be silicified or
dolomitized in outcrop as well as in the subsurface (Yon, 1966). It ranges in thickness from
approximately 20-110 feet (Figure 3c).
In Jefferson County, the Miocene age, 15 to 23 million years B.P., Hawthorn Group
overlies the St.Marks Formation and, locally, the Suwannee Umestone where the St. Marks
is absent. Lithologically, the sediments of the Hawthorn Group in Jefferson County consists
of pale olive, light greenish-gray, yellowish-gray, light gray, and moderate yellow, sandy,
waxey, phosphatic clay. The clay is Interbedded with very fine to medium, clayey quartz
sands that contain phosphate. The clays and sands are frequently cherty and often
associated with stringers of sandy calcilutites. The Hawthorn Group usually ranges in
thickness from approximately 50 to 70 feet, although, In eastern Jefferson County Yon
(1966) noted that this unit locally attains thicknesses of approximately 240 feet.
The Miccosukee Formation, which lies above the Hawthorn Group In Jefferson County,
was considered by Hendry and Yon (1966) to be Late Miocene In age. As more data has
become available, recent workers have assigned the Miccosukee Formation to the Pliocene
(COSUNA Chart, Gulf Coast Section, Braunstein et al., 1988). Locally, the Miccosukee lies
above the St. Marks Formation or the Hawthorn Group. Lithologically the Miccosukee
Formation Is an assemblage of lenticular clayey sands and clay beds which are laterally
discontinuous (Yon, 1966). Generally, the Miccosukee Formation is a moderately to poorly
sorted, coarse to fine grained, variably colored, clayey quartz sand. The thickness of the
Miccosukee Formation in Jefferson County is Irregular but ranges up to 160 feet in thickness
(Yon, 1966). These distinctive sediments can be observed along numerous road cuts
throughout the northern half of the county.
Variable thicknesses of Pleistocene, 2.8 million to 0.1 million years B.P., clayey quartz
sand overle the St. Marks Formation and the Suwannee Umestone in southern Jefferson
County and the MIccosukee Formation northwest of Waclssa. Younger Holocene, 0.1
million years B.P., deposits consisting of reworked Pleistocene sand and quartz sand
derived from the Miccosukee Formation occur along stream valleys (Yon, 1966).
MINERAL RESOURCES

The intent of this discussion is to provide Information on the distribution of various mineral
resources in Jefferson County. It will also present the results of tests applied to specific
samples from the county. These tests were carried out to define properties of a sample
related to its potential industrial uses. The data presented here are from scattered locations
and are Intended, where favorable, to provide a basis for further investigation.
The mineral commodities, which are discussed here, include limestone, dolomite, clay,
clayey sand and peat. It is essential to note that many factors must be considered before a
commodity is actually mined. These include the quality or purity of a mineral deposit, the
amount of material ultimately available for mining and the thickness of overlying but
unusable material (overburden) as well as transportation costs and distance to market.
Occasional variations between the geologic cross-sections and the mineral resources
map may occur. The mineral resources map Is designed as an overview of mineral
resources In Jefferson County. The geologic cross-sections are Included to provide
information on the distribution of llthologies from the surface to depths for which data Is
generally available. This report is Intended to document the general distribution of potential
mineral resources.
Utmestone

Limestone is a sedimentary rock composed mainly of the mineral calcite (calcium car-
bonate) with the chemical formula CaCO3. Yon (1966) noted that the Suwannee Limestone
of Ollgocene age is the most important potential source of limestone in Jefferson County.
The limestone shown on the mineral resources map accompanying this report is almost
entirely Suwannee Umestone, which contains in excess of 95 percent calcium carbonate.
The thickness of overburden should not inhibit mining in most areas as the Suwannee
Umestone lies within approximately 20 feet of the surface from just south of the town of
Wacissa to the coast and, In most areas, Is covered by 10 feet or less of overburden as
shown on the geologic map of Jefferson County (Yon, 1966).
There is no current commercial production of limestone In Jefferson County and the
limestone of the county were rated in a statewide report on mineral resources as having
low potential for development (Schmidt, et al., 1979). This rating was based on the fact that
even though limestone is present in southern Jefferson County (Knapp, 1978; Schmidt,
1979), it has not been proven economic. Yon (1966), however, noted that in 1964 limestone
was mined by the county road department and Buckeye Cellulose Company for roadbase In
the southern part of the county. Yon (1966) suggested that the Suwannee Limestone might
potentially be used as roadbase course material, agricultural limestone, or quick and
hydrated lime.

Dolomite

Dolomite is a sedimentary rock containing more than 50 percent of the mineral calcite
and dolomite, in which dolomite is the most abundant (Schmidt, et al., 1979). Although not
currently being mined, the distribution of dolomite in Jefferson County is shown on the
Mineral Resources Map. Yon (1966) noted that the dolomite in Jefferson County Is primarily
located along the Aucilla River. The thickness of the dolomite has not been determined.
Schmidt et al. (1979) classify an area In southernmost Jefferson County as having low
potential for the development of dolomite. "Low potential" In this report Indicates that
although some dolomite is present it has not been proven economic.


Clay

Clay has not been mined in Jefferson County to date. In Jefferson County, Yon (1906)
reported that montmorlonites and kaolinites are associated with the Hawthorn Group, the
Miccosukee Formation and the undiferentiated sediments of Pleistocene age. It is noted
that some of the clays from the Miccosukee Formation have a very low sand content, which
is favorable for commercial use. However, It Ia also noted that these delays generally occur In
discontinuous lenticular deposits Terrace deposits of southern Jefferson County contain
sandy mrnonrllonitcc days.
Calver (1949) sampled day sediments from a 9-1/2 foot test boring located one and one-
half mie east of Waciasa (Jf-1, section 14, Township IS, Range 3E). Tests Indicated that it
may be suitable for porous common brick (Table 1, Mineral Resources Map).
Yon (1966) arranged for seven clay samples from Jefferson County to be tested for
various physical properties. Of seven samples tested, two samples were found to be
suitablefor malng brick and one sample with the addition of alkali was poesibly suitable or
pottery or decorative tie (Jf-2, section 33ac, Township 18, Range 4E, Table 2 and Jf-3,
section 19bb, Township 18, Range SE, Table 3, Mineral Resources Map).
Clayey Sand

Sand deposits In Jefferson County are mainly associated with the Miccosukee Formation.
The sand ranges in size from very fine to very coarse grained and is predominantly fine to
medium grained. The Florida General Soils Atlas for Regional Planning Districts I and II
assigns the Lakeland-Troup soil association to much of the area mapped as clayey sand on
the Mineral Resources Map. The Lakeland-Troup association is further noted to be a good
source of sand and Is described as sandy throughout with "very thick sandy layers over
loamy subsoils" (Florida Division of State Planning, 1974). This rating of "good" Indicates
that the soil generally contains a layer of sand at least three-feet thick which has its top
within at least six-feet of the surface. It is noted, however, that the ratings do not consider
location of the water table, quality or quantity of the deposit or other factors affecting
mining.
Yon (1966) had divided the sands in Jefferson County Into primary clayey quartz sands
and secondary clayey quartz sands based on the relative purity of the sands. It must be
noted, however, that sands examined in this area are generally mixed with clay and are iron
stained so that the outlook for their commercial development is not good. Sand Is not
currently mined in Jefferson County. Past

Peat accumulates when plant material Is deposited In a wet environment in which the
action of decomposing organisms Is inhibited (Bond, at al., 1986). Although peat Is not
currently mined in Jefferson County, the county has extensive wetlands. Davis (1949) in his
comprehensive survey of Florida peatiands noted that there are a few small marshes which
contain peat as well as some tyty and bay swamps which are characterized by peat
accumulation. Jones at al., (1907) also noted the presence of organic underlying several
small marshes. Peat is used extensively in a variety of horticultural and agricultural
applications in Florida.
Undifferentiated Resources

Large areas of the county have surface and near-surface sediments comprised of sands,
sandy clays, clay, mad, and organic muck. These undifferentiated resources are present
throughout much of the northeastern and southwestern parts of Jefferson County.
The heterogeneous nature of these sediments would tend to preclude their large scale
economic marketability. Two sites in this area were sampled for grain size analysis (JF-4
and JF-5, Mineral Resources Map). Results of these analyses are shown in Table 4. The
values obtained Indicate that the sands have no economic potential at this time. Locally,
however, where costs are not prohibitive and the need is present for uses such as top soil or
road fill, extraction Is feasible. The possibility does exist that a future comprehensive
Investigation of these undifferentiated sediments may lead to economic or industrial
applications.
REFERENCES

Applin, P. L, 1951, Preliminary report on buried pre-Mesozoic rocks in Florida and adjacent
states: U.S. Geological Survey Clrcular 91, 28 p.
Arthur, J. D., 1988, Petrogenesis of Early Mesozoic tholelitein the Florida basement and
overview of Florida basement geology: Florida Geological Survey Report of investigation
97,39 p.
Bates, R. L, and Jackson, J. A., eds. 1980, Glossary of geology (2nd edition): American
Geological Institute, Falls Church, Virginia, 751 p.
Bell, 0.G., 1924, A preliminary report on the clays of Florida (exclusive of fuller's earth): in
Florida State Geological Survey, Fifteenth Annual Report 1922 1923, 266 p.
Bond, P., Campbell, K. M., and Scott, T. M., 1986, An overview of peat in Florida and related
issues: Florida Geological Survey Special Publication 27,151 p.
Braunstein, J., Huddlestun, P., Blel, R., 1988, Gulf Coast Region: Correlation of stratigraphic
units of North America (COSUNA) Project, The n Association of Petroleum
Geologists.
Calver, J. L, 1949, Florida kaolins and days: Florida Geological Survey Information Circular
2, 59 p.
Davis, J. H., Jr., 1949, The peat deposits of Florida, their occurence, development, and uses:
Florida Geological Survey Bulletin 30,247 p.
Florida Department of Transportation, 1984, Manual of Florida sampling and testing
methods, sieve analysis of fine and coarse aggregates: FDOT, designation FM 1-T 027, 6
p.
Florida Division of State Planning, 1974, The Florida general soils atlas with interpretations
for regional planning districts I and II: Florida Department of Administration, Division of
State Planning, Bureau of Comprehensive Planning, 35 p.
Healy, H. G., 1975, Terraces and shorelines of Florida: Florida Geological Survey Map
Series 71, scale 1:2,000,000.
Hendry, C. W., Jr., and Sproul, C. R., 1966, Geology and ground-water resources of Leon
County, Florida: Florida Geological Bulletin 47, 178 p.
and Yon, J. W., Jr., 1967, Stratigraphy of Upper Miocene
Miceoeukee Formation, Jefferson and Leon Counties. Florida: American Association of
Petroleum Geologists Bulletin, v. 51, p. 250-256.
Jones, G. B., Tharp, W. E., and Belden, H. L, 1907, Soils survey of Jefferson County,
Florida: U.S. Department of Agriculture, Bureau of Sols, 34 p.
Knapp, M. S., 1978, Environmental Geology Series Valdosta Sheet: Florida Bureau of
Geology Map Series 88, scale 1:250,000.
Purl, H. S., and Vernon, R. 0., 1964, Summary of the geology of Florida and a guidebook of
the classic exposures: Florida Geological Survey Special Publication 5 (revised), 312 p.
Schmidt, W., 1979, Environmental Geology Series Tallahassee Sheet: Florida Bureau of
Geology Map Series 90, scale 1:250,000.
Hoenstine, R. W., Knapp, M. S., Lane, E., Ogden, G. M., Jr., and Scott, T. M.,
1979, The limestone, dolomite and coquina resources of Florida: Florida Bureau of
Geology Report of Investigation 88, 54 p.
Yon, J. W., Jr., 1966, Geology of Jefferson County, Florida: Florida Bureau of Geology
Bulletin 48, 119 p.
Table 1
Physical Properties of Wacissa Clay JF-1, Mineral Resources Map
(From Calver, 1949)

SPlasticity, judged by feel............................................... Good
W ater of plasticity......................................................... 31.01%
Linear air shrinkage....................................................... 8.6%
Modulus of rupture, average.. 210.0 pounds per square Inch.
Slaking tst..........................................................................Fast
Color ............................................................................ Brown


Fire Tests:


Temp. Near Sheer Absorption
OF Percent Percent


Porosity or
Par cat


1742 1.0 14.9 34.8 Reddish Orange
1922 2.5 14.8 35.0 Reddish Orange
2102 2.0 14.1 34.0 Brick Red
2174 2.5 14.4 34.0 Brick Red
2246 2.5 13.6 32.5 Brick Red
2390 2.5 13.8 33.3 Brick Red


Table 2


Table 2
Physical Properties for Clay JF-2, Mineral Resources Map
(From Yon, 1966)

Working characteristcs................... short working, stick, plastic
Water of plasticity..................................................... 25.0
Drying shrinkage............................ ..........
Dry strength.............................................................Fair, warping


Slow Firing Test:

Temp. near Shrinkage Absorption
OF Per coa Per cent Hardness Color


Fair Hard
Fair Hard
Hard
Hard
Very Hard
Very Hard


ULight Brown
Light Brown
Brown
Chocolate
Chocolate
Chocolate


Table 3
Physical Properties for Clay JF-3, Mineral Resources Map
(From Yon, 1966)

Working characteristics............... long working, smooth, plastic
W after of plasticity................................................. ............ 2 .0%
Drying shrinkage................................................... ......... .. 5%
ry strength...........................................................Fair, warping

Slow Firing Test:


Temp. Unear Shrinkage
OF Per cent


Absorption
Par cent


arridnew


Fair Hard
Fair Hard
Hard
Hard
Very Hard
Steel Hard


cnlnr


Tan
Tan
Tan
Tan
Buff Tan
OUve Tan


Potential use: light color, some cracking, shrinkage a little
high, addition of alkali might make a pottery or decorative tie.

Table* Screen aoyse of sand In Jefferson county, Florida.

Labortory Tet hte
eponelts sron Iinylsis
iteem no. and Crauitatie weiht Percent Retained

Section Nsthod Finenssu
slipte N. Trmhp, SRen of Satin 4 8 16 30 0s 100 Noduts*

sec 3bs
Jf-4 m, MN Spot 6.73 8.12 10.81 19.21 43.35 100.0 1.M

ms ltbb
Jft- TIN. RMa pot 0 0.27 0.85 6.94 .09 t0.o 1.41


*Finenss Nodulus: A mew of evaluating and and s ort deposits tthlh consists of sieving sempls
through stant rd set of steves, sdlirn the ctmultatiln eight percentes of the Individual screens,
dividing by 100, and comparin the resultant finienss modulus uber to various specflcetloen
roqulrson ts(tese and Jackluen, 19M).

The finr e modulus is an Indt of the finens or coarMeM u of an aggregate., but gives no Idea of
grading. The higher the finenesso moduus the coMer the greete (ASM, 197).
The method of leve analysis presented here folious that outlined In AST 107., v. 4.02, section
C 136-11. The redr I s ao referred to the Floride DOT Manual of Forid suptingn ad testing
asthodi for susgnltes, FDOT, dsinttion FN I-T 027.


The well and quarry system used in this report uses
the rectangular system of section. township and
rang tfor identification. The weal or outcrop number
consilsts of six parts: W lotr well or L for quarry.
county abreviation, the Township, Range. and
Section, and the quarter/quarter location
within the section.


FIGURE 1
GEOMORPHOLOGY
(modified from White, 1970)


-N-




11


SCALE FOR FIGURES 1,2 AND 3a


FIGURE 3a

CROSS SECTION LOCATIONS


P55TfaTSR

":0I.. r,


VTiTIMCL IAEXAMdATIOS I APIUATKLY 1M W TiNG

FIGURE 3b
CROSS SECTION A-A'


P5519657565


EXPLANATION

215'-320' HAZLEHURST TERRACE

170"-215' COHARIE TERRACE

100'-170' SUNOERLAND TERRACE

70'-100' WICOMICO TERRACE

42"-70' PENHOLOWAY TERRACE

25'-42' TALBOT TERRACE

10'-25' PAMLICO TERRACE

0-10' SILVER BLUFF TERRACE


FIGURE 2
TERRACES AND SHORELINES
(modified from Healy, 1975)


FIGURE 3c
CROSS SECTION B-B'


SCALE FOR FIGURES 3b AND 3c


~___


_~