The Geology of Kentucky
Notes
Kentucky Is Divided Into 6 Distinct Regions
1._________________________________________________________________
2.________________________________________________________________________
3._________________________________________________________________________
4._________________________________________________________________________
5._________________________________________________________________________
6._________________________________________________________________________
Bluegrass Region
• Characteristics of this region are gently rolling hills and __________________________
_________________________________________________________________________________
• Layers of Ordovician aged limestone has been _________________________________ along
the crest of a region called ___________________________________________.
• The rolling hills are caused by the weathering of these thick beds of ________________
__________________ which is characteristic of Kentucky.
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Eastern Kentucky Coal Field
Is dominated by forested hills and deeply________________________________ valleys.
In southeastern Kentucky the highest elevation in the State, (before mining), was
________________________ in Harlan County ___________________ feet.
Pine Mountain another important feature is best described as a _________________-mile long
ridge that extends from Jellico, Tennessee to Elkhorn City, Kentucky.
It is _______________feet high in Letcher County and is a direct result of the Pine Mountain
Thrust Fault.
Appalachian Mountains built for the last time during end of ______________________, block of
Earth's crust was ____________ and __________________________________.
The Eastern Kentucky Coal Field
•
This region is formed from resistant Pennsylvanian-age ___________________________
and___________________________ in the form of an __________________________.
•
An escarpment is a ridge of gently tipped rock strata with a long,
_______________________________________________________________________.
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The sandstones weather and are eroded along the escarpment.
•
It is the region bordering the Bluegrass. It consists of____________________________, steep
sloping,_____________________________________________.
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The hills are monadnocks or erosional remnants that were originally continuous with the
_________________ Plateau, but were _______________________________________.
•
Hills composed the Mississippian-age “Borden Formation” shales, which are
_______________________________to erosion than the overlying limestones and
_____________________________________.
The results cliffs, ____________________________________, rock shelters, waterfalls,
____________________ and __________________, the most scenic areas in Kentucky.
Knobs Region
Jackson Purchase or Mississippi Embayment
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Cretaceous and Tertiary & Quaternary ______________________ occur at the surface.
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Local relief is less than _______________________, and the lowest spot in the State, at only
________________________________________________ sea level, is found here.
These deposits are _________________________ (not cemented) sediment instead of rock.
Are easily __________________________________________, so, this part of Kentucky is flat
with numerous ______________________________________________________.
• Is underlain by ___________________________ of the __________________________ Fault
Zone, the most active __________________________ in the central United States.
• The strongest earthquakes in the history of the United States occurred during the winter of
______________________ were caused by movements along the________________
________________________________ and extreme western _____________________.
Mississippian Plateau /Pennyrile Region
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Consists of __________________________________________________bedrock.
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Karst is used to define this type of terrain.
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This terrain occurs because ______________________________ in the eastern and southern
parts are ______________________________________(i.e. will dissolve) by waters moving
____________________________________________.
Characterized by tens of thousands of sink holes, _______________________________,
_______________________________, springs, and ____________________________.
Region dominated by thick deposits of ________________________________________
____________________________.
• This type of region contains some of the _____________________________________
_______________________________________________.
• The ____________________________________________________________________ cave
system is the _____________________________________________ in the world.
• ____________________________, in ________________________, is very well known.
• All of theses systems are formed in _____________________________________ in the
_______________________________________________________________ Region.
Western Kentucky Coal Field
• Smaller than____________________________________________________________.
• It is the southern edge of a larger geologic feature called ________________________, includes
Indiana & ___________________________________________________ fields.
• An outcrop of __________________________________________, defines the limits of the
_____________________________________________________________ Fields.
Pennsylvanian aged strata
•Pennsylvanian aged strata ____________________________________________________
___________________________________________________on the geologic maps we will use.
•The ____________________________ in Kentucky is composed of ___________________
_______________________________________, and coals. Thin limestone beds may also occur.
•____________ is Kentucky's leading ____________________ commodity.
•Because of the coal-bearing ______________________ strata, we are among the top ______
states in the Nation in annual __________________________(160 to 180 million tons annually).
•All of Kentucky was covered by _________________ of ____________________ age at one
time but, _____________ has completely removed them from all areas but the _________ fields.
•Pennsylvanian Period, often called __________________, was a time of _________________
land and ____________.
•When ________________________, the low coastal plains were covered with luxuriant
__________________ of seed ferns, ferns, scale trees, and dense vegetation.
•During heavy ________________, this dense vegetation fell to the _____________________
to form (___________).
•This peat later became (millions of years) _________________.
•When _______________________, and it did periodically, it covered the peat & ___________
large inland ________________ seas.
•During these times, (many thousands of years), many types of ______________ (sea-
dwelling) ________________________________________ lived in the shallow seas that would
become _________________.
•Now Pennsylvanian ____________________ are found in Kentucky; like _________________
(Cnidarians), _______________, ______________, snails (gastropods), clams (pelecypods),
squid-like animals (cephalopods), ______________ (Echinoderms), fish teeth (Pisces), and
microscopic animals.
Mississippian-age strata
•Mississippian-age strata shown in light blue on the geologic map, are ___________________
______________________________________________________________________________.
•A thick sequence of ________________ can contain numerous ________________________
beneath the surface.
•Then the same limestone is ___________________ where it occurs at the surface. Reed
quarry in western Kentucky, produces more limestone than any other quarry in the United
States.
•The limestone also ______________________ systems, including the Mammoth Cave-Flint
Ridge cave system, and ______________________________.
•Mississippian rocks are exposed at the surface in the ________________________
(Pennyrile) and occur below the surface in both of the _________________________.
•Mississippian rocks are absent in the ___________________ Region and in most of the
____________________ region.
•During most of the Mississippian, _________________________________________________
______________________________ may have been visible at times in central Kentucky.
•Periodically, during the _______________ of the Mississippian, ________________ and low
___________________ covered large parts of Kentucky.
•During _________________ the sea would come in and cover the region.
•At this time _________________________ were created in these shallow seas.
•Through the _________________________ many caves were developed in these limestones.
•So this area is now known as one of the world's most famous ____________________ areas.
Mississippian Fossils
•Mississippian fossils in Kentucky are very similar to _____________________________ fossils.
•Also some different life forms appeared like _________________ and
____________________ forms of echinoderms.
•When there was visible land in the form of _________________________, land plants and
animals thrived. So we have fossils of them as well.
•Since this area was a shallow sea we can also find ____________________.
These were
_________________________ in the state until one was found in western Kentucky.
Devonian aged strata
•Devonian aged strata shown in red.
•Devonian strata consists of _____________________________ and a thick deposit of dark
gray to black ____________________.
•The limestones are mined in the _________________ area and sometimes contain abundant
fossils.
•The thick, dark gray to black shales are the ____________________________in many areas
of Kentucky.
•The color of the shales comes from ______________________________________________.
•Late in the Devonian, organic ____________ were deposited in a shallow ____________ that
covered most of the eastern ______________________.
•When these ___________________ sediments were buried deeper beneath the surface,
_______________________________________ converted some of the organic material in the
rock to liquid and gaseous forms.
• The liquid form is called __________. The gaseous form is ___________________________.
•Eastern Kentucky has the largest gas field in the state and is estimated to contain
____________________ feet of gas. (Big Sandy Gas Field).
•The oil found in Kentucky started out in _________________________, but due to gravity
migrated to other rock layers
Silurian Strata
•The Ordovician rocks are ______________________________________________, shown in red.
•These rocks out crop in the __________________ & consist mainly of limestones & _______________.
•In the Big Sinking-Irvine area, these rocks dip beneath the ______________, and because they are very
_______________ they form natural reservoirs for __________.
•The Silurian rock strata pinches out to the south in Boyle, Casey, Lincoln, & Montgomery Counties.
•At this point, where Silurian strata are missing, __________________ tend to take their place and lie
over _________________ rocks.
•This is called an _______________________ because a large segment of geologic time is missing from
the rock record.
•Silurian strata almost completely surrounds the ________________________ in the form of the Knobs.
•In the Blue Grass Silurian rock strata does not exist but, ___________________________ in other parts
of Kentucky.
•A shallow __________________ covered Kentucky during most of the Silurian which allowed for the
formation of thin beds of ____________________.
•All Silurian rocks found in Kentucky are marine (sea-dwelling) so all the fossils are the invertebrates.
Ordovician Strata
•The Bluegrass Region of the State is composed of ___________________________ from the
Ordovician Period, and are colored pink on the geologic map.
•The Ordovician strata lies _________________________ the surface.
•The oldest rocks at the surface in Kentucky are ______________________ from the ____________
______________________________ (approximately 450 million years ago).
•These rock strata are exposed along the _________________________ of the Kentucky River (for
example, near Camp Nelson, in Jessamine County.
•Ordovician limestones are quarried from _____________________________________ in construction.
•Some of the limestones also produce _________________________________ that is bottled and sold
for drinking water.
•The city of ____________________ was founded at ________________________, which flows from
Ordovician limestones.
•The oldest rocks exposed at the surface in Kentucky are _____________________ and are exposed in
the Blue Grass Region.
•Rocks deposited during the first half of the Ordovician Period occur entirely below the surface
throughout Kentucky.
•Some of these deep rocks contain oil, so some oil wells have been drilled down to them.
•During most of the Ordovician, ______________________________by shallow tropical seas.
•Accordingly, the fossils found in Kentucky's Ordovician rocks are ___________________________
invertebrates.
•All common Ordovician fossils found in Kentucky are virtually the same as Pennsylvanian except
_____________________________________now makes an appearance.
Strata of Cretaceous Age
•In western Kentucky, ________________________________________________________________,
older rocks are not overlain by Pennsylvanian rocks.
•However, are overlain by Cretaceous (________________________________) strata shown in green
on the geologic map.
•This relationship is another unconformity.
•Cretaceous strata on the map are the only areas in Kentucky where _____________________________
might be found, although none yet.
•The Cretaceous Period was the last period in the _____________________________.
•Much of the Cretaceous strata in Kentucky are ________________________________ (i.e., they are
not rocks yet).
•Sediment grains (sand, silt) have not been _______________________ to form rock in many cases.
•Some areas contain a __________________________________________________ (some peat still
present), but it is not currently economic to mine.
•The most common fossils are coalified tree limbs, but no dinosaurs yet.
Neogene and Paleogene (Tertiary) Age Strata
•Paleogene and Neogene (_______________________________) rocks & sediments were deposited
after the dinosaur ____________________, during the ___________________________ Shown in green.
•Tertiary sediments in Kentucky include many deposits of ______________________, which can be
used for ceramics and enameling.
•Kentucky is the second largest producer of ball clay.
•Common fossils are coalified _________________________________________of lignite rank, few
others.