Go back to the NC Map Go to the New River Page Go to the Stone Mountain Page Go to the Pilot Mountain Page Go to the Medoc Mountain page Go to the Carolina Beach page Go to the Jones Lake page Go to the Pettigrew State Park page Go to the Singletary Lake page Go to the Waccamaw State Park page

Stone Mountain is a granitic exfoliation dome that attracts rock climbers, hikers, and naturalists and dominates Stone Mountain State Park. The park contains an impressive 200-foot high waterfall where Big Sandy Creek plunges over a granitic face.

Some features that you may encounter at Stone Mountain include:


Exfoliation


Yosemite Nation Park
Photograph byJimmie D. Agnew

Yosemite Nation Park
Photograph byJimmie D. Agnew

 

Erosion strips away surface rocks such that over time it can expose rocks that were once several miles deep within the Earth. When these once underlying rocks are on the surface, they are no longer subject to the great pressure that comes with being positioned at a greater depth. The release in pressure on these underlying rocks causes them to expand upward and develop fractures parallel to the present ground surface. The slabs of rock that form are referred to as exfoliation sheets. When exfoliation of an igneous mass occurs it is akin to the flaking off or removal of layers of an onion---as already exfoliated sheets are eroded away new layers are exposed, fractured, and themselves exfoliated. Sheeting is another term for exfoliation.



Yosemite Nation Park
Photograph byJimmie D. Agnew

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Joints

Joints- Mohonk Reserve, NY
Photograph by Heidi Glaesel

Joints are cracks that develop in rock due to stress but along which there has been no appreciable movement. Joints may develop during the exfoliation process and be parallel to the surface. Outdoor enthusiasts may use steep angled and vertical joints as ascent routes for rock climbing.

Joints- Wind River Range, WY
Photograph by Heidi Glaesel

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Monadnocks

Stone Mountain, GA
Photograph by Heidi Glaesel

Monadnocks are erosional remnants of resistant rock that rise slightly above a landscape of limited relief. They often take the form of isolated hills on a peneplain, an extensive area that owes its overall low relief to erosion.

Stone Mountain, GA
Photograph by Heidi Glaesel

Waterfalls

Wind River Range, WY
Photograph by Heidi Glaesel

 

Waterfalls are formed by the abrupt descent of a stream over a prominent knickpoint or irregularity in a stream-channel profile. Especially tall or wide waterfalls are often of interest to sightseers.

Ithaca, NY
Photograph by Heidi Glaesel

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Weathering Pits

Weathering Pits- Top of Stone Mountain, NC

Weathering Pits are rounded, irregularly shaped depressions in rock that are formed by chemical and physical processes. The depressions occur where certain minerals weather more rapidly than others. The depressions collect water and enlarge over time to the extent that they merge with other depressions to create a distinctive "pock marked" surface which in turn serve as an area where lichen and mosses grow. The mosses and lichen provide organic acids that decompose the minerals to produce a thin soil layer which grows over time such that it may eventually support communities of grass, flowers, or even trees.

Weathering Pits- Top of Stone Mountain, NC

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Links

References
P. Albert Carpenter, III 1989. A Geologic Guide to North Carolina's State Parks. NC Geological Survey. Bulletin 91.
Tom L. McKinght 1999. Physical Geography. Upper Saddle River, NJ: Prentice Hall.