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Vagabonds & Sojourners Tramping Geology The Appalachian Mountains Session 3
The Southern Appalachian Mountains: North Carolina, Tennessee, Georgia, and Alabama
Remember from previous sessions:
But first, Geology in the News
Extraction begun of lithium, magnesium, & copper from very hot brines used to generate electricity in the Salton Sea of southern California
Lithium and magnesium are important industrial raw materials in short
supply in the USA
The Canadian-USA oil pipeline
Bringing oil from the Canadian tar sands to mid-America
Unhappy “campers” in the exploration for Marcellus shale gas in Pennsylvania
Unhappy “campers” in the exploration for Marcellus shale gas in Pennsylvania
A new book you may or may not want to read
The Quest: what’s in the future and our options
Let’s try serious conservation of our energy resources
From Patricia Windsor
From Patricia Windsor
Government bureaucracy is delaying the creation of a large number of new, high pay jobs by delaying permits to drill in the USA offshore,
New York state, etc.What’s not mentioned is the need now to begin the recruiting and training of 1,000’s of new geologists and engineers to handle the phenomenal growth of the oil and gas industry in the next 40 years
Remember from previous sessions:
Appalachian Mountains
Pre-Clovis artifact sites15,000 years ago
Possible Area of Human Habitation 15,000 Years Ago
Also from previous sessions:
1. mountains are created when rocky crustal plates collide and when they shear past one another
2. mountain building creates a variety of newmetamorphic and igneous rocks
3. the Appalachian Mountains were modified by a continental glacier about 12,000 years ago
4. the Appalachian Mountains have exposed rocks at the surface that have shaped the history of eastern North America
Rocks of the Appalachian Provinces
Blu
e R
idge
Mou
ntai
ns
Gre
at V
alle
y
Valley & Ridge Piedm
ont
Coa
stal
Pla
in
Con
tinen
tal S
helf
Rocks in the Geologic Provinces of the Appalachians
Let’s find these provinces in North Carolina
A. J. Eardley, 1962,Structure Geology of North America
Allegheny Plateau
SandstonesShalesLimestones
ShalesSlateLimestonesMarble
SchistGneiss Granite
Gneiss
Blue Ridge mountains
300 milli
on year old m
etamorphic rocks
Geologic Provinces of North Carolina
Coastal P
lain
1 to 65 m
illion year o
ld sand & clay
Offshore
Contin
ental Shelf
Recent sand &
clay
Piedmont hills
300 m
illion year o
ld
metamorphic & ig
neous rocks
The Piedmont geologic province Igneous & metamorphic rocks
Where do we find igneous basalt rocks?
Triassic age red sandstones & shales and black lava basalt
Great Smoky Mountains 600 million year old sandstones & shales
Low lands: Valleys of red sandstones & shales Ridges & domes of black lava rock (basalt)
North Carolina
“Red sandstones & Black lava basalt rocks” Triassic Age
How old is Triassic?
Geologic Time: Last 570 Million Years
TriassicPeriod
570
,000
,000
yea
rs
Back to the red and black rocks of eastern North America
Appalachians formed
Geologic Map of the USA
Rocks at the surface below soil and vegetation
Can you find North Carolina?
North Carolina
“Red & Black Rocks” Triassic Age
Geological Map: Northeast USA
Triassic best seen in New Jersey, so let’s look there
Geologic Map of New Jersey
Triassic age rocks
Ridges of black basalt rocks
Let’s look at the basalt ridges
Hudson River
NY
NJ
Cliff face of Triassic age
black igneous Basalt rock
The Triassic Palisades in NJ Opposite New York City
Very old metamorphic rocks
Triassic age red shale
Triassic age basalt
Triassic age red shale& sandstone
Hudson River
NY NJ
View seen on Google Earth
Now that we know all about rocks, let’s begin our traverse of the Appalachians in the Blue Ridge Mountains of North Carolina
Geologic Cross Section: Hudson River Valley at NYC
New York City
Fold
ed V
alle
y & R
idge
Offshore
Contin
ental S
helf
Great Valley
Blue Ridge Mountains
Great Smoky Mountains
Piedmont “hills”
Coastal Plain
Geological Provinces of the Appalachians
Focus on western North Carolina
Blue Ridge mountains 300 million year old metamorphic rocks
Geologic Provinces of North Carolina
Coastal P
lain
1 to 65 m
illion year o
ld sand & clay
Offshore
Contin
ental Shelf
Recent sand &
clay
The Piedmont geologic province Igneous & metamorphic rocks
Focus on the Great Smoky & Blue Ridge mountains
Triassic age red sandstones & shales and black lava Basalt
Great Smoky Mountains 600 million year old sandstones & shales
West-East Geologic Cross Section North Carolina
From P. B. King, 1959, The Evolution of North America
Tenn NC
Let’s see how the Great Smoky Mountains fit into the regional topography
Tennessee River
Hammond Citation World Atlas, 1962
Great Smoky Mountains
Rivers & the Great Smoky Mountains
How might rivers have affected the arrival of First Nation Peoples?
Tennessee River
Hammond Citation World Atlas, 1962
Great Smoky Mountains
How might rivers channeled the arrival of First Nation Peoples?
Remember the glacier 15,000 years ago
Possible track of early human migration during glacial time
Mountains might have provided a refuge away from glacial melt water
Let’s see what’s interesting in theGreat Smoky Mountain province
Visitors to the Great Smoky Mountains National Park wait for darkness, when fireflies emerge. For two weeks each June, thousands of them blink in synchrony
Let’s see what else is interesting in the Great Smoky Mountain province
Great S
moky Mountains-600 m
illion year o
ld\
meta-sandsto
nes & shales
Blue Ridge Mountains- m
etamorphic & igneous ro
cks
Valley & Ridge-Sandstones, li
mestones, & shales
What’s special in the Great Smoky Mountains in North Carolina?
Road Map: Western North Carolina and Eastern Tennessee
Great Smoky Mts.National Park
North Carolina
Gatlinburg, Tenn.
Ancestral home of the Eastern Cherokee Indians
The Great Smoky Mountains of North Carolina
Up close
Great Smoky Mts. National Park
Cherokee
Gatlinburg
600 millio
n year old ro
cks of the Great S
moky Mountains
270
mill
ion y
ear o
ld
Met
amorp
hic &
igneo
us ro
cks
of the
Blue
ridge
Mounta
ins
North Carolina
Rock ages on the geologic time chart
Age of rocksGreat Smoky Mts
Age of Blue Ridge Mts
Appalachian geosynclinal sedimentary rocks convertedinto metamorphic & igneous rocks of the Blue Ridge Mountains
What natural resources** are found in the Great Smoky & Blue Ridge mountains?
**Resource that Native Americans &
Colonial Americans might need.
Natural Resources of North Carolina
Focus on western North Carolina: Natural resources and rock types
Ashville
Geologic Map: Western North Carolina
Natural Resources of North CarolinaFocus on western North Carolina
Metamorphic industrial materials of no value until late in the industrial age
Copper could have been used by early humans
Widely scattered re
sources in th
e metamorp
hic
& ig
neous rocks of th
e Piedmont Pro
vince
Great S
moky M
ountain
s rocks
Blue Ridge Mountains ro
cks
What counties have these resources?
Note the concentration of mineralization near the Smoky-Blue Ridge contact
Counties in western North Carolina with commercial resources
What are some of the well known places in western North Carolina?
Ashville
Spruce PineMineral District
Focus on the Blue Ridge Mountains
The Blue Ridge Mountain boundary with the Piedmont Province
Blue
Ridge M
ounta
ins
Piedmont province
Ashville, the big city of the Blue Ridge Mountains
Ashville
Ashville and the Blue Ridge Parkway
Blue Ridge P
arkway
North Carolina
Ashville, North Carolina
Blue Ridge Mountains
Ashville to Black Rock to Spruce Pine
Black Mountain & Montreat
Black Mountain
Spruce Pine
Montreat
Black Mountain & Montreat, NC
Blue Ridge Mountains
Blue Ridge Parkway to Spruce Pine, Mitchell Co, NC: center of the Spruce Pine Mineral District
Spruce Pine
Up the Blue Ridge Parkway to Spruce Pine
Up the Blue Ridge Parkway to Little Switzerland
Blue Ridge Parkway
Little Switzerland to Spruce Pine, NC
Spruce Pine
Blue Ridge Parkway
Quarry
Spruce Pine & Pegmatites quarries
What is a pegmatite?
Spruce Pine & nearby quarries
Pegmatites are important because they often contain rare earth minerals and gemstones, such as aquamarine, tourmaline, topaz, fluorite, and apatite. They are also mined for feldspar and mica used in industrial products.
A pegmatite is a very coarse-grained granite usually in veins or irregular rock masses in schists and gneisses
Sandi in Spruce Pine, age 2
Feldspar - Feldspar was first mined in North Carolina in 1911 in the Spruce Pine district, the main feldspar-producing district in North America. Original mining was from pegmatite bodies but current mining is from alaskite,a very coarse-grained, light-colored, feldspar-quartz-muscovite rock. By-product mica and silica are also recovered. Most of the production is from mines in Mitchell County, The main uses of feldspar are in whiteware, tile, and glass fiber insulation. Feldspar is used both in the body of the ware and the glaze of ceramics
Mica - Mica mining began on a large scale in western North Carolina about 1868. The area has become the most important producer of mica in the U.S. Sheet mica was the principal product for many years, but other materials have eliminated many of the uses for sheet mica. Consequently, North Carolina has not produced significant amounts of sheet mica since about 1962. Scrap mica is still produced in large quantities. Primary sources are the alaskite and pegmatites rocks that produce feldspar.North Carolina annually leads the nation in the production of scrap mica, producing about 60 percent of the total. Primary production is from Mitchell County in the Spruce Pine district,
http://www.geology.enr.state.nc.us/Mineral%20resources/mineralresources.html
Some old, abandoned pegmatite mines
Today, Panning for gem stones: Little Switzerland, North Carolina
Piedmont geologic pro
vince:
metamorp
hic & ig
neous rocksAshville
Black Mountain
Montreat
Spruce Pine
Blue Ridge M
ountains Province
metamorp
hic & ig
neous rocks
Why are so many pegmatites found here?
Pegmatites
Valley & Ridge Province
GreatSmokyMtsProvince
Blur RidgeMountainsProvince
Piedmont Province
Granites
Cross Section: Tenn-North Carolina
But why concentrated in and around Mitchell Co?
Natural Resources of North Carolina
Widely scattered re
sources in th
e metamorp
hic
& ig
neous rocks of th
e Piedmont Pro
vince
Great S
moky M
ountain
s rocks
Blue Ridge Mountains ro
cks
Note the concentration of mineralization near the Smoky-Blue Ridge contactWhy here?
Sierra Nevada Mountains: Melted Paleozoic Sediments
Sierra Nevada ProvinceBasin & RangeProvince
Great BasinProvince
Apply the Sierra Nevada model to the Blue Ridge Mountains
Granite
Sierra Nevada Mountains Analog Analog Applied to Appalachia
Piedmont Province
Valley & Ridge Province
Atlantic OceanBlue Ridge Province
Great SmokyGreat Valley provinces
Spruce PinePegmatites
But why only here near Spruce Pine?
Today’s surface of theBlue Ridge Mountains
Metamorphic Rocks Metamorphic Rocks
Granite furnace
Spruce PinePegmatites
What natural resources are west of North Carolina in Tennessee?
Spruce Pine Mineral District; top of a granite column?
Valley &
Ridge P
rovince
Great Smoky Mountains Province
Knoxville Area: Favorable naturalresources for early civilizations: major river, iron, & coal
Great S
moky Pro
vince
Blue Ridge P
rovince
Appalachians in Georgia
Is there farming in the Tennessee River flood plain east of Knoxville?
Tennessee River East of Knoxville
Tennessee River
Tennessee River Flood Plain
possible area of early
Native Americ
an farm
ing
What Native Americans lived here in the area of Knoxville?
Native American Tribal Areas
http://www.google.com/#sclient=psy&hl=en&rlz=1R2GPEA_en&source=hp&q=native+american+tribes&rlz=1R2GPEA_en&aq=3&aqi=g5&aql=&oq=&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=c924775ad1dac27b&biw=1242&bih=638
Up close here
Knoxville Spruce Pine
Georgia
Back to the regional geologic map and then to Georgia
Native American Tribal Lands: SE USA
Valley &
Ridge P
rovince
Great Smoky Mountains Province
Knoxville Area: Favorable naturalresources for early civilizations: major river, iron, & coal
Great S
moky Pro
vince
Blue Ridge P
rovince
Piedmont Pro
vince
Appalachians in Georgia
GeorgiaNote: Iron but no nearby coal
What’s going on here in Alabama?
GeorgiaAlabama
Piedmont metamorphic & igneous ro
cksBlue Ridge
Valley & RidgeMajor iron & coal at Birmingham
Birmingham is on a river. Does it have a flood plain?
Birmingham
No river flood plains
Conclusion: Native Americans living in the Birmingham area had access to iron & coal but no extensive flood plain farm land.
What Native American tribal nation lived in the Birmingham area?.
Knoxville Spruce Pine
Georgia
Native American Tribal Lands: SE USA
Birmingham
Alabama
Back to the regional geologic map
North Carolina
Georgia
Coastal Plain: “young” sandstones & shales
Piedmont: old metamorphic & igneous rocks
Alabama
Valley & Ridge: sandstones & shales
Great Smoky M
ountains
old meta- s
andstones & shales
Blue Ridge M
ountains:
old metamorp
hic & ig
neous rocks
Cumbe
rland
Pla
teau
: san
dsto
nes
& sha
les
Review: Southern Appalachia Mountains
And next week: Virginia to New England
North Carolina
Georgia
Coastal Plain: “young” sandstones & shales
Piedmont: old metamorphic & igneous rocks
Alabama
Valley & Ridge: sandstones & shales
Great Smoky M
ountains
old meta- s
andstones & shales
Blue Ridge M
ountains:
old metamorp
hic & ig
neous rocks
Cum
berla
nd P
late
au: s
ands
tone
s &
sha
les
What natural resources will we find up here in Virginia?
Virginia
Great Valley
First, what natural resources are found in theValley & Ridge and Cumberland Plateau provinces?
Virginia to New England
First, what natural resources are found in theValley & Ridge and Cumberland Plateau provinces?
North Carolina
Southern Appalachians
Cumberland Plateau &Valley & Ridge provinces
Coal Deposits: Eastern USA
Cumberland Plateau &Valley & Ridge provinces
Coal Deposits: USA
Yellow=ligniteGrays=bituminousRed=anthasite
http://www.eia.gov/oil_gas/rpd/shale_gas.pdf
Why are there some of the world’s largest coal, oil and gas deposits in the western margin of the Appalachian Mountains?
Cumberland Plateau &Valley & Ridge provinces
After Eardley, 1962
App
alac
hian
Geo
sync
line
20,
000
plus
feet
thic
k be
fore
mou
ntai
n bu
ildin
g
Origin of Coal, Oil, & Gas Deposits in Appalachia
Paleo-geologic map by Eardley shows thickness of rocks 310 million years old
LandCoastal tropical swamps & marshes rich in plant debris = coal sources
Ocean
Mou
ntai
ns
Deep water, organic plankton rich shales = oil & gas sources
A modern example of future sources of coal, oil, and gas
Modern Example of Future Coal, Oil, & Coal Deposits**
Marsh & swamp tropical muds = future coal
Deep water organic rich muds = future oil & gas source rocks
These areas must be located in the Tropics in order to be good source rocks
New subject: Stream Capture Do you remember this slide?
GeorgiaAlabama
New subject: Stream Capture Notice the two rivers
Whenever you find a right angle in the main course of a river; suspect a Stream Capture
Appalachia is “full” of right angle rivers!
Let’s see what’s going on
Hammond Citation World Atlas, 1962
Rivers of Eastern & Central USA
Notice the Tennessee-Mississippi rivers
Tennessee River today
Hammond Citation World Atlas, 1962
Rivers of the Southern Appalachians
Mobile River today
Headwaters of theMobile River before capture by the Tennessee River
Main channel of theMobile River before it was “beheaded” by the Tennessee River
Austin to Alamogordo, NM
PecosRiver
Rio GrandeRiver
Note the “dog leg” in the Rio Grande at Big Bend Nat. Pk.Upper Rio Grande captured by the Pecos River River Capture
Rivers
River Capture
Head-ward erosion
What natural resources are essential forthe development of early civilizations?
Let’s look at the world’s early civilizations?
Natural Resources & Early Civilizations Historically what was required?
1. Northern Temperate Zone 2. Shielded from melting continental glacier
by mountain range(s)3. Major river flood plain suitable for farming4. Access to ores of copper, tin, &/or arsenic
Bronze AgeLarge scale farming & metal tools and weapons
5. Iron and coal6. Iron, coal, and oil7. Iron, coal, oil, and uranium
Iron Ages
A quick review
Eastern Hemisphere:Eurasia-
1. elongated west-east 2. located in Northern Temperate Zone
Northern Temperate Zone
A quick review
Eastern Hemisphere: Eurasia: 1. elongated west-east 2. located in Northern Temperate Zone Africa: 1. elongated north-south 2. located in the tropical climate zone
A quick reviewIndia and Africa collide with Eurasia forming west-east mountains
extending from the Atlantic to the Pacific oceans
A quick review
African rift valleys formHuman species appears
Humans migrate into Eurasia “channeled” by the collision mountains
A quick review
African rift valleys formHuman species appears
Humans migrate into Eurasia “channeled” by the collision mountains
Most recent continental glacier creates hostile climate for humans living north of collision mountains
A quick review
African rift valleys formHuman species appears
Most recent continental glacier creates hostile climate for humans living north of collision mountains
Humans migrate into Eurasia “channeled” by the collision mountains
Most favorable latitude for early human civilizations
A quick review
African rift valleys formHuman species appears
Most recent continental glacier creates hostile climate for humans living north of collision mountains
Most favorable latitude for early human civilizations
China: most favored geological province for early civilizations
Humans migrate into Eurasia “channeled” by the collision mountains
African rift valleys formHuman species appears
Mountain Trend, aka remnant of Tethys Seaway: 1. erosion exposes natural resource ores; Cu, Sn, & Fe and Coal 2. provides 10,000 mile long west-east avenues of commerce3. greatest concentration of iron and coal at each end of trend
Most favorable latitude for early human civilizations
4. intermediate concentrations of Iron and Coal
Most favorable latitude for early human civilizations
Erosion & deposition create six major river flood plains in the most favorable latitude for early human civilizations
YellowYangtze
GangesIndus
TigrisEuphrates
Nile
The geological province of China has most favorable natural resources for developing and maintaining major early civilizations.
YellowYangtze
GangesIndus
TigrisEuphrates
Nile
Natural Resources;1. Metallic ores2. Major river flood plains3. Mountain shield
So let’s look in North America for a major river, ores of copper and tin as well as iron, coal, & oil