Question: Which are the oldest rocks in the Great Smoky Mountains?
About the article "Great Smoky Mountains National Park", section "Geology".

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Bote Mountain is a mountain in Great Smoky Mountains National Park of Tennessee, in the United States.
Bote Mountain is located in the Great Smoky Mountains, which began forming in the late Carboniferous and through the early Triassic, approximately .
The oldest rocks of the Great Smoky Mountains, however, date from the Neoproterozoic, approximately .
Those rocks are sedimentary rocks, and were deposited on an ancient ocean floor on the edge of a supercontinent.
Bote Mountain was named because of a misunderstanding when, in the 1830s, Cherokee workers were asked which route a new road would follow.
They pointed towards Bote Mountain and said "vote", which was interpreted by the white workers, who thought they were naming the mountain, as "bote".
Hence, the mountain was named "Bote Mountain".
The Bote Mountain Trail follows the crest of the mountain, and intersects the Appalachian Trail at Spence Field. 
The majority of rocks in the Great Smoky Mountains National Park are Late Precambrian rocks that are part of the Ocoee Supergroup formation.
This group consists of metamorphosed sandstones, phyllites, schists, and slate.
Early Precambrian rocks are not only the oldest rocks in the park but also the dominant rock type in sites such as the Raven Fork Valley and upper Tuckasegee River between Cherokee and Bryson City.
They primarily consist of metamorphic gneiss, granite, and schist.
Cambrian sedimentary rocks can be found among the bottom of the Foothills to the northwest and in limestone coves such as Cades Cove.
One of the most visited attractions in the mountains is Cades Cove which is a window or an area where older rocks made out of sandstone surround the valley floor of younger rocks made out of limestone.
The oldest rocks in the Smokies are the Precambrian gneiss and schists which were formed over a billion years ago from the accumulation of marine sediments and igneous rock.
In the Late Precambrian period, the primordial ocean expanded and the more recent Ocoee Supergroup rocks formed from the accumulation of eroding land mass onto the continental shelf.
At the end of the Paleozoic era, the ocean deposited a thick layer of marine sediments which left behind sedimentary rock.
During the Ordovician period, the collision of North American and African plates initiated the Alleghenian orogeny that created the Appalachian range.
The Mesozoic era was dictated by the rapid erosion of softer sedimentary rocks and re-exposed the older Ocoee Supergroup formations.
The Lower Mount Cammerer Trail is an American hiking trail, in the Great Smoky Mountains National Park of Cocke County, Tennessee.
The trail ascends Mount Cammerer (elev.
; 1,502 m), leading (via a connection with the Appalachian Trail) to a small, untraditional firetower at the summit, from which panoramic views of Cocke County, the main range of the Great Smoky Mountains, and the dominating presence of Mount Guyot are all prominent. 
Smoky Mountain is an adjective for things related to the Great Smoky Mountains (as in the Smoky Mountain National Park) and may refer to the following landforms: Smoky Mountain (California), a Guadalupe Mountains summit at [http://maps.google.com/maps?hl=en&q=%22Smoky+Mountain%22+California&ie=UTF8&hq=&hnear=Smoky+Mountain,+Mariposa,+California+95338&gl=us&ei=SRKFTMOrMoSdlgeL0NGtDg&ved=0CBMQ8gEwAA&ll=37.441064,-120.031857&spn=0.020547,0.052142&t=p&z=15] Smoky Mountain (Idaho), a Cassia County, Idaho, summit at  Smoky Mountain (Tennessee), a Cumberland Mountains summit of  Smoky Mountain (Utah), a summit northwest of the Glen Canyon National Recreation Area at  Smoky Mountains (Moon)  
Most of the rocks in the Great Smoky Mountains consist of Late Precambrian rocks that are part of a formation known as the Ocoee Supergroup.
The Ocoee Supergroup consists primarily of slightly metamorphosed sandstones, phyllites, schists, and slate.
Early Precambrian rocks, which include the oldest rocks in the Smokies, comprise the dominant rock type in the Raven Fork Valley (near Oconaluftee) and upper Tuckasegee River between Cherokee and Bryson City.
They consist primarily of metamorphic gneiss, granite, and schist.
Cambrian sedimentary rocks are found among the outer reaches of the Foothills to the northwest and in limestone coves such as Cades Cove.
The Precambrian gneiss and schists— the oldest rocks in the Smokies— formed over a billion years ago from the accumulation of marine sediments and igneous rock in a primordial ocean.
In the Late Precambrian period, this ocean expanded, and the more recent Ocoee Supergroup rocks formed from accumulations of the eroding land mass onto the ocean's continental shelf.
By the end of the Paleozoic era, the ancient ocean had deposited a thick layer of marine sediments which left behind sedimentary rocks such as limestone.
During the Ordovician period, the North American and African plates collided, destroying the ancient ocean and initiating the Alleghenian orogeny— the mountain-building epoch that created the Appalachian range.
The Mesozoic era saw the rapid erosion of the softer sedimentary rocks from the new mountains, re-exposing the older Ocoee Supergroup formations.
Around 20,000 years ago, subarctic glaciers advanced southward across North America, and although they never reached the Smokies, the advancing glaciers led to colder mean annual temperatures and an increase in precipitation throughout the range.
Trees were unable to survive at the higher elevations, and were replaced by tundra vegetation.
Spruce-fir forests occupied the valleys and slopes below approximately .
The persistent freezing and thawing during this period created the large blockfields that are often found at the base of large mountain slopes.
Between 16,500 and 12,500 years ago, the glaciers to the north retreated and mean annual temperatures rose.
The tundra vegetation disappeared, and the spruce-fir forests retreated to the highest elevations.
Hardwood trees moved into the region from the coastal plains, replacing the spruce-fir forests in the lower elevations.
The temperatures continued warming until around 6,000 years ago, when they began to gradually grow cooler.