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CAROLINA GEOLOGICAL SOCIETY
Guidebook for 1992 Annual Meeting
Pages 83-86
UPPER CLAIBORNIAN COASTAL MARINE SANDS OF EASTERN GEORGIA AND THE SAVANNAH RIVER
AREA
Paul Huddlestun
Georgia Geologic Survey
19 Martin Luther King Jr. Dr., SW
Atlanta, Georgia 30334
INTRODUCTION
Hetrick (1990) and Huddlestun and Hetirck (1991)
named the Perry Sand for a distinctive formation west of the
Ocmulgee River in Georgia. The Perry sand consists of stratified,
relatively pure, well to very well sorted, fine to very
fine grained quartz sand. All along its outcrop belt in Georgia,
from Randolph County in the west to Houston County in
the east, the Perry Sand occurs as a band not much greater
than 10 miles (16 km) across (Fig. 1). Huddlestun and
Hetrick (1991) correlated the Perry Sand with the Lisbon
Formation on physical grounds. Except for local concentrations
of burrows, the Perry Sand is not known to be fossiliferous.
The Lisbon Formation occurs in the stratigraphic
position of the Perry Sand in the shallow subsurface a few
miles to the south of outcropping Perry Sand. Conversely, a
few miles north of cores that contain Lisbon Formation and
overlying and underlying units, only Perry Sand occurs in
the stratigraphic position of the Lisbon.
The Perry Sand is considered to be a coastal marine
lithofacies of the inner to middle neritic Lisbon Formation.
In west central Georgia, the facies change is abrupt and there
appears to no transgressive or regressive facies relationships
between the Perry and the Lisbon.
The Perry Sand can be traced in outcrop as far east as
the vicinity of the Ocmulgee River in Georgia (between the
south side of Warner Robins and the brewery north of
Clinchfield). We could not trace it farther east because, if the
Perry lithofacies is a mappable unit east of the Ocmulgee
River, it occurs only in the shallow subsurface where we currently
have no core control (Fig. 1).
In west central Georgia, the Perry Sand grades laterally
updip (landward) into the Mossy Creek Sand of Huddlestun
and Hetrick (1991). The Mossy Creek Sand is lithologically
more variable than the Perry Sand. In its finer grained lithofacies,
the Mossy Creek Sand resembles the Perry Sand but
is coarser grained (generally medium grained sand), is less
well sorted, and the bedding is larger in scale and more
crude. In its coarsest lithofacies, the Mossy Creek occurs as
coarse grained, poorly sorted, tidal channel deposits with
large scale cross bedding and common clay (kaolin) rip up
clasts. Typical Ophiomorpha nodosa and bioturbation occur
locally in this facies. The Mossy Creek Sand is also a coastal
marine formation, deposited landward of the Perry Sand and,
in places, the coarser facies of the Mossy Creek Sand
strongly resembles the coarser facies of the younger Tobacco
Road Sand in Georgia. In west central, Georgia, the areal
extent of the Mossy Creek is much broader than that of the
Perry and geometrically is a blanket deposit.
The Mossy Creek Sand grades laterally eastward across
the Ocmulgee River into the Tertiary hard kaolin or Claiborne
kaolin (Jeffersonville member of the Huber Formation
of Huddlestun and Hetrick (1991) [informal name]). I have
seen upper Claibornian Mossy Creek sand lithofacies in only
a few mines between the Ocmulgee and Oconee Rivers in
Georgia. However, the coarse grained and intensely cross
bedded channel lithofacies facies of the upper Claibornian
may not be easy to distinguish from the Lower Paleocene
Marion Member of the Huber Formation of Huddlestun and
Hetrick (1991) or from the basal Upper Eocene channel
sands (LaMoreaux, 1946; Huddlestun and Hetrick, 1991).
The upper part of the type section of the Huber Formation as
described by Buie (1978) may be Claibornian and consists in
part of cross-bedded, poorly sorted, coarse-grained sands
(see Huddlestun and Hetrick, 1991, p. 117 – 118). Unfortunately
the type section of the Huber Formation has been
excavated and is not longer accessible. I also have not identified
any sand lithofacies of the exposed Claibornian east of
the Oconee River in Washington County, Georgia. In that
area, it appears that the Barnwell Group overlies the Marion
member of the Huber Formation, Claiborne hard kaolin, or
Upper Eocene channel sands.
In outcrop in the Savannah River area in Georgia, the
only deposits of probable late Claibornian age that I have
identified (also pers. Com., J. Hetrick, 1992) fall within the
range of the lithologies of the Jeffersonville member of the
Huber Formation. Neither the Perry nor Mossy Creek Sands
have been identified in outcrop in the Savannah River area of
Georgia.
In western South Carolina, on the other hand, there are
two exposures of Perry like sand that I am familiar with: one
being deposits identified as Huber Formation at Stop 7 of
Nystrom and others (1982). The upper sand overlying the
Cretaceous kaolin at the Bell kaolin pit in western Aiken
county is, to me, indistinguishable from the finer grained
lithofacies of the Mossy Creek Sand. These three sand exposures
contain the appropriate lithologies and occur in the
same stratigraphic positions of the Perry Sand and Mossy
Creek Sand of southwestern and central west Georgia. The
question is whether these sand bodies are continuous fro
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