• By: Trent Southerland

• Georgia is the site of a rich geologic history, covering at

least 1 billion years.

• The state can be divided into five regions or provinces:

Coastal Plain, Piedmont, Blue Ridge, Valley and

Ridge, and Appalachian Plateau.

• A large percentage of Georgia’s wealth is derived from

geological resources such as marble, granite, and kaolin.

• Georgia’s geology is some of the most varied and

interesting terrain, with each region having its own

distinctive look, rock types, and geological history.

I collected samples

from Piedmont and

Valley and Ridge

regions.

• Metamorphic rocks form by applying

heat, pressure, and/or chemically active fluids to

preexisting igneous, sedimentary, and other metamorphic

rocks.

• An example of a foliated metamorphic rock is slate. Slate

generally appears dull and displays an admirable rock

cleavage.

• An example of a non-foliated metamorphic rock is

marble. Marble is composed basically of the mineral

calcite. Marble is fairly malleable, allowing it to be used to

create monuments such as the Taj Mahal.

Sample #1

• This rock appears dull

and displays excellent

rock cleavage (Two

pieces came off while

I was taking a

picture!). I believe this

rock is slate, a foliated

metamorphic rock.

• Sedimentary rocks are created from weathering of

preexisting rocks.

• Three categories of sedimentary rocks are recognized:

detrital, chemical, and organic.

• Detrital sedimentary rocks are derived from both

mechanical and chemical weathering.

• Chemical sedimentary rocks are produced by chemical

weathering (inorganic or biologic processes).

• Organic sedimentary rocks are created from undecayed

plant structures such as leaves, bark, and wood.

I think this rock is jasper, a type of chert. It is a

compact, hard, chemical sedimentary rock and has a reddish

tint (my camera doesn’t pick up the red very well).

Sample #3

Sam

ple

#4

• Igneous rocks are derived from magma that cools and

solidifies.

• Extrusive igneous rocks form when lava solidifies on the

surface.

• Intrusive igneous rocks are created by magma that

crystalizes beneath the Earth’s surface.

• Crystallization is the process of ions from cooling magma

arranging themselves into orderly patterns. The slower

the cooling the larger the crystals.

• The mineral composition of an igneous rock is directly

tied to the chemical makeup of the parent magma and

the type of crystallization.

Sample #5

• Pamela J. W. Gore (2007, Jan 7). Geologic History of

Georgia: Overview. Retrieved from

http://www.georgiaencyclopedia.org/nge/Article.jsp?path=

/ScienceMedicine/EarthSciences/GeologicalProvinces&id

=h-3510

• William J. Frazier (2007, Jan 7). Geologic Regions of

Georgia: Overview. Retrieved from

http://www.georgiaencyclopedia.org/nge/Article.jsp?path=

/ScienceMedicine/EarthSciences/GeologicalProvinces&id

=h-1159

• Edward J. Tarbuck, Frederick K. Lutgens, & Denise Tasa.

(2011). Earth: an introduction to physical geology (10th

ed.). Upper Saddie River, NJ: Prentice Hall