Download ch11 - earthjay science

THE EARTH THROUGH TIME
TENTH EDITION
H A R O L D L. L E V I N
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
1
CHAPTER 11
Late Paleozoic Events
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
2
PALEOZOIC
OVERVIEW
FIGURE 10-1 Major events of the
Paleozoic Era.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
3
PALEOZOIC ERA
Paleozoic can be divided into:

Early Paleozoic = Cambrian, Ordovician and
Silurian

Late Paleozoic = Devonian, Mississippian,
Pennsylvanian, and Permian
 160

million years long
Mississippian & Pennsylvanian Periods are also
referred to with one name - Carboniferous Period.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
4
LATE PALEOZOIC PLATE GEOGRAPHY


The supercontinent
Pangea assembled
as the continents
collided during Late
Paleozoic.
Larger continents
grew by addition of
island arcs and
microcontinents
around their edges.
FIGURE 11-1 Paleogeography of the
Late Paleozoic.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
5
LATE PALEOZOIC OROGENIES OF
EASTERN NORTH AMERICA
Continental collisions caused several orogenies
or mountain-building events in eastern
North America.
Acadian orogeny and Caledonian orogeny
Laurentia + Baltica  Laurasia
and
A volcanic island arc (Avalon terrane or Carolina terrane)
collides with eastern North America.
Alleghanian orogeny (eastern North America) and
Hercynian orogeny (central Europe)
Laurasia + Gondwana  Pangea
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
6
LATE PALEOZOIC OROGENIES IN
EASTERN NORTH AMERICA

The Acadian and Alleghanian orogenies were
the result of the closure of the Iapetus
Ocean and continental collisions which
resulted in the formation of the
supercontinent Pangea.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
7
PHYSIOGRAPHIC
PROVINCES OF THE
APPALACHIAN REGION
IN EASTERN NORTH
AMERICA.
FIGURE 11-27 Eastern U.S. physiographic
provinces.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
8
LATE PALEOZOIC SEDIMENTARY SEQUENCES

Shallow epicontinental seas transgressed
and regressed across Laurasia (North
America) during Late Paleozoic as the
glaciers melted and enlarged.

These sequences are bounded by (or
separated by) unconformities.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
9
LATE PALEOZOIC SEDIMENTARY
SEQUENCES

Two major transgressions occurred in North
America during Late Paleozoic:
 Kaskaskia (Devonian-Mississippian)
 Absaroka (Pennsylvanian-Permian)

During regressions, such as the one between
Mississippian and Pennsylvanian, the former
seafloor was exposed to erosion, creating one of
the most widespread regional unconformities in
the world.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
10
NORTH AMERICAN CRATONIC SEQUENCES
Green = sedimentary
deposits
Yellow = missing
strata associated with
unconformities
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
11
DEVONIAN PALEOGEOGRAPHY
(After C. R. Scotese, et al., 1979, Jour. Geol. 83(3):217–277)

As Late Paleozoic began, the continents were fairly
fragmented and separate, particularly in the Northern
Hemisphere.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
12
DEVONIAN PALEOGEOGRAPHY
(After C. R. Scotese, et al., 1979, Jour. Geol. 83(3):217–277)


There is an extensive sedimentary record for Devonian.
Note that North America sat on the equator, with warm, tropical
climatic conditions.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
13
DEVONIAN PALEOGEOGRAPHY
(After C. R. Scotese, et al., 1979, Jour. Geol. 83(3):217–277)

A large continental landmass named Gondwana (composed
of South America, Africa, India, Antarctica, and Australia)
was present in the southern hemisphere, on or near the
South Pole.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
14
DEVONIAN PALEOGEOGRAPHY
(After C. R. Scotese, et al., 1979, Jour. Geol. 83(3):217–277)

Laurentia and Baltica collided to form Laurasia in the
Caledonian orogeny affecting northeastern Canada,
Greenland, and Europe).
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
15
DEVONIAN PALEOGEOGRAPHY
(After C. R. Scotese, et al., 1979, Jour. Geol. 83(3):217–277)

A volcanic island arc or exotic terrane, called the Avalon
terrane (or Carolina terrane), collided with Eastern North
America in the Acadian orogeny. A thick sequences of
sedimentary rocks are interbedded with rhyolitic volcanic
rocks and granitic intrusions.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
16
DEVONIAN
PALEOGEOGRAPHY
FIGURE 11-4


© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
The Acadian highlands
in eastern North
America (orange), form a
continuous belt with the
Caledonian Mountains
adjacent to Greenland
and Europe.
Erosion of these
mountains resulted in
the deposition of the
Catskill Red beds in the
Appalachian area, and
the Old Red Sandstone
in Europe.
17
DEVONIAN
PALEOGEOGRAPHY

Sea levels were high
worldwide during
Devonian (indicating that
there were no glaciers).

Much of the North
American continent was
flooded by shallow seas.
FIGURE 11-4
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
18
DEVONIAN SEDIMENTARY DEPOSITS
The seas regressed from the continents at
the end of Early Paleozoic as a result of the
Ordovician-Silurian glaciation.
 Gradual flooding of the North American
craton occurred during Late Paleozoic,
reaching its maximum extent during
Mississippian Period. This new inland sea
was called the Kaskaskia sea.

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
19
DEVONIAN SEDIMENTARY DEPOSITS
In eastern North America, initial deposits of the
Kaskaskia sea were clean quartz sands, such
as the Devonian Oriskany Sandstone, used for
glass making because of its purity.
 As the sea continued to transgress, shales,
and then limestones with reef-forming coral
were deposited over the sands.
 In areas where water circulation was more
restricted, evaporites were deposited.
 Reefs and carbonates indicate a warm climate.
 Evaporites suggest dry conditions.

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
20
DEVONIAN SEDIMENTARY DEPOSITS




After the Acadian orogeny, carbonate
sedimentation was followed by deposition of clastic
sediments.
Clastic sediments are thicker and coarser to the
east, nearer their source area in the Acadian
highlands.
Primarily continental red beds (stream deposits).
Wedge-shaped deposit called the Catskill clastic
wedge or Catskill delta (although these are not
deltaic deposits).
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
21
DEVONIAN SEDIMENTARY DEPOSITS

Similar Devonian red beds are also present
in Europe, such as the Old Red Sandstone.

The red color of the sandstone indicates
deposition under oxidizing conditions in
continental or non-marine environments.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
22
DEVONIAN SEDIMENTARY DEPOSITS
FIGURE 11-21
Panorama of the
Catskill clastic wedge
viewed from a point
above southcentral
Pennsylvania.
FIGURE 11-20 Upper
Devonian sedimentary rocks
in the northeastern U.S.;
Catskill clastic wedge in New
York.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
23
DEVONIAN SEDIMENTARY DEPOSITS
Catskill clastic wedge deposits



© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Isopach (sediment
thickness) and
lithofacies map of
Upper Devonian in the
eastern U.S.
The Catskill clastic
wedge sediments are
thicker and coarser in
the east.
The sediments become
finer-grained westward,
away from the Acadian
highland source area.
24
CHATTANOOGA SHALE





Farther west, black shales were deposited in a thin
unit (less than about 10-20 m thick) over a wide
area (Chattanooga Shale) during Late Devonian
and Early Mississippian.
Offshore equivalent of the 3000 m thick Catskill
clastic wedge.
An important marker bed for regional correlation.
High organic carbon content, along with finely
disseminated pyrite, and uranium.
Chattanooga Shale was deposited in stagnant,
oxygen-deficient water.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
25
WILLISTON BASIN
In the Williston Basin area (South Dakota,
Montana, and adjacent Canada), extensive
reefs formed.
 Restricted circulation within the reefencircled basin led to the deposition of thick
evaporite deposits.
 The reefs of the Williston Basin provided
permeable structures into which petroleum
migrated, forming rich oil fields.

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
26
CARBONIFEROUS
In North America, Carboniferous consists of
two periods: Mississippian and
Pennsylvanian.
 Mississippian
is Early Carboniferous.
 Pennsylvanian
is Late Carboniferous.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
27
MISSISSIPPIAN

The name "Mississippian" is derived from
exposures of rock in the valley region of the
Mississippi River.

Mississippian sedimentary deposits contain
abundant limestone with fossils of crinoids,
blastoids, bryozoans, and fusulinid
foraminifera.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
28
PENNSYLVANIAN

Pennsylvanian rocks are dominated by coalrich sediments that were deposited in
swamps and deltas.

Coal deposits are particularly well developed
in Pennsylvania.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
29
MISSISSIPPIAN
PALEOGEOGRAPHY
Landmass in eastern
North America and
Europe (yellow),
formed as the
mountains (orange)
eroded after
Caledonian and
Acadian orogenies.
FIGURE 11-8 Mississippian
Period paleogeography.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
30
MISSISSIPPIAN
PALEOGEOGRAPHY

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Although a large
mountain range was
present in the
Appalachian area,
another orogeny was
soon to occur, as
indicated by the
arrows and the words
"Africa approaching"
along the right side of
the map.
31
MISSISSIPPIAN
PALEOGEOGRAPHY
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.

Much of North America
was covered by a
shallow epicontinental
sea.

North America sat on
the equator, so
temperatures were
warm.

Note the Antler
highlands in the
western U.S.
32
MISSISSIPPIAN SEDIMENTARY DEPOSITS

By Mississippian, the Acadian highlands were
reduced in size by erosion, and were no longer
releasing large quantities of sediment.

In the east, near the remaining highlands, nonmarine shales, sandstones, and conglomerates
were deposited.

These sediments belong to the Pocono Group.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
33
MISSISSIPPIAN SEDIMENTARY DEPOSITS




As muddy sediment from the eroding highlands
decreased, carbonate deposition became
widespread in the warm, shallow Kaskaskia sea.
Mississippian limestones contain abundant
crinoids, blastoids, bryozoans, and fusulinid
foraminifera.
The widespread blanket of carbonate rocks
deposited during this time is called the great
Mississippian lime bank.
In places, Mississippian limestones are more than
700 m thick.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
34
CRINOIDS
(top) National Museum of Natural History/ Smithsonian Institution;
(right) Harold Levin)
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
35
MISSISSIPPIAN SEDIMENTARY DEPOSITS




Sands, clays, and thin layers of carbonates were
deposited during Late Mississippian time as the
Kaskaskia sea regressed.
These rocks are a source of petroleum in Illinois.
They appear to have been deposited in stream
valleys developed on the former seafloor.
Farther west, the Williston basin (South Dakota,
Montana, and part of Canada) continued to have
extensive reefs developed around.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
36
MISSISSIPPIAN SEDIMENTARY DEPOSITS




In the Gulf Coast area, slow
deposition continued from Early
Devonian to Late Mississippian.
Carbonates predominated in the
more northerly shelf zone.
Cherty rocks called novaculites
were deposited in deeper waters
to the south. Novaculites are
composed of microcrystalline
quartz, which has been
subjected to heat and pressure.
Arkansas novaculite is used as a
whetstone to sharpen steel
knives and tools.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Harold Levin
37
MISSISSIPPIAN SEDIMENTARY DEPOSITS


Graywackes and shales spread into the
depositional basin near the end of Mississippian,
forming a clastic wedge more than 8000 m thick,
that thickened and coarsened to the south, where
a new mountain range had formed and was
eroding.
The remnants of this mountain range are the
Ouachita Mountains of Arkansas and Oklahoma,
and the Marathon Mountains of southwestern
Texas.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
38
MISSISSIPPIAN SEDIMENTARY DEPOSITS
The Kaskaskia sea retreated from the craton
at the end of Mississippian.
 This event is marked by one of the most
widespread unconformities in the world.
This unconformity separates Mississippian
from Pennsylvanian.
 The overlying Pennsylvanian rocks were
deposited under very different conditions.

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
39
ALLEGHANIAN OROGENY
FIGURE 11-1


During Late Paleozoic, northwestern Africa collided with southeastern
North America, causing the Alleghanian orogeny, and building the
Appalachian mountains.
The orogeny began during Mississippian and continued through
Pennsylvanian and Permian.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
40
ALLEGHANIAN OROGENY
• South America collided with the Gulf Coast region of North
America, forming the Ouachita Mountains, a
southwestern continuation of the Alleghanian orogenic belt.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
41
THE ALLEGHANIAN OROGENY
The Alleghanian orogeny produced folds in the
Appalachian Valley and Ridge province, and large
thrust faults in the southern Appalachians.
Many folds are asymmetrically overturned to the
northwest, and surfaces of thrust faults dip to the
southeast.
FIGURE 11-27
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
42
THE ALLEGHANIAN OROGENY
Blue Ridge and Piedmont metamorphic and igneous
rocks form a sheet ranging from 6-15 km thick,
overlying relatively flat-lying lower Paleozoic
sedimentary rocks. This type of tectonic deformation
is called "thin-skinned tectonics."
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
43
PLATE TECTONICS MODEL FOR THE
CONTINENTAL COLLISIONS DURING LATE
PALEOZOIC
FIGURE 11-26 Plate tectonic model for late Paleozoic continental collisions.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
44
PANGEA

By Late Carboniferous, a large continental landmass called
Pangea, had formed by the collision of Laurasia (North America
plus Europe) with Gondwana (the southern continents of Africa,
South America, Australia, Antarctica, and India).
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
45
LATE PALEOZOIC OROGENIES OF
WESTERN NORTH AMERICA

In the western part of North America, the Antler orogeny began
during Devonian with the subduction of oceanic lithosphere
beneath the western margin of the continent.

The Antler Orogeny continued into Mississippian and
Pennsylvanian.
FIGURE 11-32 Interpretation of the Cordilleran orogenic belt shortly after the Antler orogeny.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
46
LATE PALEOZOIC OROGENIES OF
WESTERN NORTH AMERICA

A volcanic island arc collided with the western margin of North
America, crushing sediments and causing thrust faulting (Roberts
Mountains Thrust Fault of Nevada).

Continental rise and slope deposits were thrust as much as 80
km over shallow water sediments of the former continental shelf.
FIGURE 11-32 Interpretation of the Cordilleran orogenic belt shortly after the Antler orogeny.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
47
PANGEA ON THE SOUTH POLE

The supercontinent, Pangea, sat over the South Pole. When a
continent is over a pole, conditions are right for a glaciation, if
the climate is cold and if sufficient moisture is present.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
48
IAPETUS OCEAN CLOSED


The Iapetus Ocean (or Proto-Atlantic), completely closed by Late
Carboniferous.
Closure of the Iapetus Ocean disrupted global ocean circulation
and caused currents to be diverted from the tropics to more
polar areas, contributing to glaciation.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
49
LATE PALEOZOIC EVAPORITES


The presence of evaporites (E) indicates that the
climate was at least locally dry.
This was probably due in part to changes in global
oceanic and atmospheric circulation induced by the
closure of the Iapetus, as well as by orogeny.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
50
LATE PALEOZOIC GLACIAL DEPOSITS

Glacial deposits are present in the southern hemisphere,
indicating that a glaciation occurred during Carboniferous
and Permian.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
51
PENNSYLVANIAN
PALEOGEOGRAPHY

Large landmass in the
east, with extensive
lowlands (yellow).

Appalachian
Mountains (orange)
have formed as a
result of the
Alleghanian orogeny.
FIGURE 11-9 Pennsylvanian Period
paleogeography
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
52
PENNSYLVANIAN PALEOGEOGRAPHY

Sediment eroding from the Appalachian
Mountains was transported to the west into
the epicontinental sea that covered much of
North America during Mississippian.

These sedimentary deposits have built a
broad plain to the west, with alternating nonmarine and marine deposits, as the sea
transgressed and regressed.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
53
PENNSYLVANIAN
PALEOGEOGRAPHY

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Coal swamps
formed along the
western edge of the
Appalachian
Mountains, in what
was basically a
tropical rainforest
setting.
54
PENNSYLVANIAN
PALEOGEOGRAPHY

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Uplifts in the
southern and
southwestern North
America
(Uncompahgre
mountains or
ancestral Rockies,
and others), and the
Antler Mountains in
the western U.S.
55
PENNSYLVANIAN SEDIMENTARY DEPOSITS

The erosion of the Antler Mountains provided
detrital sediment that was transported into
adjacent basins.

Thick sequences of Pennsylvanian and
Permian shelf sediments accumulated in the
area now occupied by the Wasatch and
Oquirrh Mountains in Utah.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
56
PENNSYLVANIAN SEDIMENTARY DEPOSITS

The Absaroka sea began to transgress upon the
North American craton near the beginning of
Middle Pennsylvanian.

The rocks in the eastern half of the U.S. are
predominantly interbedded marine and nonmarine
sediments, indicating the advance and retreat of
the sea.

Each nonmarine-marine sequence is called a
cyclothem.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
57
PENNSYLVANIAN CYCLOTHEM



A typical Pennsylvanian
cyclothem contains 10
units.
The lower half consist of
nonmarine sediments,
topped by a coal deposit.
The coal is overlain by
marine deposits,
indicating the advance of
the sea into the swampy,
vegetated area.
FIGURE 11-11 Coal-bearing cyclothems.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
58
MARINE AND NON-MARINE DEPOSITS

The repetitious interbedding of non-marine
and marine sedimentary deposits indicates
either:
 Episodic
regional subsidence and uplift
OR
 Eustatic (worldwide) sea level changes related to
Carboniferous-Permian glaciation in Gondwana.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
59
COAL AND PLANT FOSSILS


Pennsylvanian coal deposits
are mined extensively in the
Appalachian area, the Illinois
basin, and in Europe.
They are commonly associated
with rocks containing plant
fossils.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
60
SOUTHWESTERN NORTH AMERICA

SW part of the North American craton experienced mountain
building during Pennsylvanian.

The highlands are called the Uncompahgre Mountains (or
ancestral Rockies) in southwestern Colorado, and the
Oklahoma Mountains of western Oklahoma.

These mountains and
related uplifts resulted
from movement along
large, nearly vertical
faults.
FIGURE 11-12 Principal highland
areas, southwestern part of the
craton, Pennsylvanian time.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
61
COLORADO FRONT RANGE

The Colorado Front Range-Pedernal uplifts
extending north-south through central
Colorado formed at this time.

Precambrian igneous and metamorphic rocks
are now exposed in the cores of these eroded
mountain ranges.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
62
PENNSYLVANIAN AND PERMIAN
SANDSTONE DEPOSITS

Erosion produced great wedge-shaped deposits of red arkosic
sandstone during Pennsylvanian and Permian, some of which is
exposed in Colorado as:
 The "flatirons" near Boulder
 The rocks at Red Rocks Amphitheatre near Morrison, west of Denver
 The Garden of the Gods, near Colorado Springs
FIGURE 11-13
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
63
OTHER UPLIFTS

Other uplifts also formed, including the Zuni-Fort
Defiance uplift, the Amarillo mountains, and the
Oklahoma mountains (represented today by the
Arbuckle and Wichita mountains).

The origin of these mountains may be related to
the collision of Gondwana along the southern edge
of the North American craton in the Ouachita
orogenic belt.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
64
OTHER UPLIFTS
Crustal adjustments to relieve stress may have resulted in
the deformation that produced the highlands and
associated basins (such as the Early Pennsylvanian Paradox
basin, which contains evaporites and petroleum deposits).
FIGURE 11-15 Generalized cross-section through the Paradox
basin in Utah/Colorado.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
65
PARADOX
BASIN

The Paradox basin lies southwest of the
Uncompahgre mountains.

Clastic sediments from the mountains were deposited
along the northeastern side of the basin.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
66
PARADOX
BASIN
• The Paradox basin was flooded by the Absaroka sea during
Early Pennsylvanian.
• Shales were deposited over Mississippian limestone.
• The basin became restricted and thick beds of evaporites
(salt, gypsum and anhydrite) were deposited.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
67
PARADOX
BASIN
• Reef-like algal mounds, associated with fossiliferous and
oolitic limestones, developed along the western rim of the
basin.
• The reefs serve as petroleum reservoirs.
• Near the end of Pennsylvanian, the basin filled with arkosic
sediments eroded from the Uncompahgre highlands.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
68
REGRESSION OF THE ABSAROKA SEA

The Absaroka sea, which began its
transgression at the beginning of
Pennsylvanian, began a slow and irregular
regression before the end of Pennsylvanian,
which continued into Permian.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
69
PERMIAN PALEOGEOGRAPHY



During Permian, the continents collided and joined to form the
supercontinent, Pangea.
Pangea was surrounded by a huge ocean called Panthalassa.
The oceanic area east of Pangea, and between Africa and
Europe was called the Tethys Sea.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
70
PERMIAN PALEOGEOGRAPHY

Continental collision was accompanied by orogeny,
and the Appalachian mountain chain reached its peak
during the Alleghanian orogeny.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
71
PERMIAN PALEOGEOGRAPHY



Late Permian was a time of widespread regression of the
seas.
The global map above indicates that sea levels were low
worldwide.
The vast epicontinental seas that once covered North America
and parts of other continents were gone.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
72
PERMIAN PALEOGEOGRAPHY

The Gondwana part of Pangea continued to sit
atop the South Pole, and glaciation continued
into Permian.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
73
PERMIAN PALEOCLIMATIC INDICATORS
Red circles are coal
deposits (humid climates
during interglacial
periods, possibly
associated with glacial
meltwaters).
Blue triangles are glacial
tillites.
Irregular green areas are
evaporites (arid climates).
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
74
PERMIAN EVAPORITES
Cold air holds less moisture
than warm air, and the
climate became arid during
Permian.
Evaporite deposits (gypsum
and salt) accumulated in the
green areas on the map.
There are more Permian salt
deposits than any other age.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
75
END OF THE COAL SWAMPS

Drying of climates at low latitudes led to
contraction of coal swamps and extinctions
among spore-bearing plants and amphibians
that required moist conditions.

Because of the drying, gymnosperms (seed
plants, including conifers) replaced many
spore-bearing plants, which require moist
conditions.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
76
OROGENY AND CLIMATE

Orogenies probably also affected the climate.

Locations of mountains can affect climate
and control precipitation (rain-shadow effect).

Deserts form on the downwind side of
mountain ranges.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
77
PERMIAN
PALEOGEOGRAPHY
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.

The eastern 2/3 of
North America consisted
of lowlands, undergoing
erosion.

Continental red beds
were deposited locally.
78
PERMIAN
PALEOGEOGRAPHY





© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
Appalachian mountains
in the east.
Ouachita mountains in
the southeast.
Farther west are the
"Ancestral Rockies."
Antler Mountains have
been eroded, and are
called uplands.
Subduction and
volcanism continue in
the far west.
79
PERMIAN SEDIMENTARY DEPOSITS
The Absaroka sea continued its regression
during Permian.
 Fossiliferous limestones were deposited in
the Absaroka sea, overlain in places by
shales, red beds, and evaporites.
 The Kaibab Limestone, which forms the cliffs
along the rim of the Grand Canyon, is a
Permian carbonate deposit.

© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
80
PHOSPHATE DEPOSITS IN NW U.S.




Deep marine basin in the Wyoming, Montana, and
Idaho area filled with cherts, sandstones, and
mudstones of the Phosphoria Formation.
Formation named for layers of dark phosphatic
sediments and phosphorites.
Phosphorite = dark gray variety of calcium
phosphate. May have formed by upwelling of
phosphorus-rich sea water from deeper parts of
basin.
Phosphate is mined for fertilizers and other
products.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
81
PERMIAN BASINS IN WEST TEXAS AND
NEW MEXICO

Several irregularly subsiding basins (such as the
Delaware basin) developed between shallow
submerged carbonate platforms.
FIGURE 11-16
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
82
PERMIAN BASINS IN WEST TEXAS AND
NEW MEXICO

Reefs formed along the basin
edges (Capitan Limestone).

The ancient reef forms the
steep El Capitan promontory
in the Guadalupe Mountains.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
83
PERMIAN BASINS IN WEST TEXAS AND
NEW MEXICO

In the shallow water lagoons behind the reefs, thin
limestones, evaporites, and red beds were deposited.
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
84
PALEOZOIC
REVIEW
© 2013 JOHN WILEY & SONS, INC. ALL RIGHTS RESERVED.
85
IMAGE CREDITS
•FIGURE 11-27 Eastern U.S. physiographic provinces. Source: After F. A. Cook et al., 1979, Geology 7:563–567.
• FIGURE 11-4 Devonian Period paleography. Source: Harold Levin.
• FIGURE 11-20 Upper Devonian sedimentary rocks in the northeastern U.S.; Catskill clastic wedge in New York.
Source: (A) After W. D. Sevon, 1985, Geol. Soc. Amer. Special Paper ZOI: 71–90, and W.G. Ayrton, 1963,
Pennsylvania Geol. Survey Report. 39(4):3–6. (B) Based on Classic Studies by G. H. Chadwick and G. A. Cooper
Completed between 1924 and 1942.
• FIGURE 11-21 Panorama of the Catskill clastic wedge viewed from a point above southcentral Pennsylvania.
Modified from Woodrow, D.L. and Sevon, W.D., eds., The Catskill Delta: Geological Society of America Special Paper
201:51-63.
• FIGURE 11-8 Mississippian Period paleogeography. Source: Harold Levin.
• FIGURE 11-26 Plate tectonic model for late Paleozoic continental collisions. Source: After P. E. Socks and D. T.
Secor Jr. 1990, Science 25:1702–1705.
• FIGURE 11-32 Interpretation of the Cordilleran orogenic belt shortly after the Antler orogeny. Source: Harold Levin.
• FIGURE 11-9 Pennsylvanian Period paleogeography. Source: Harold Levin.
• FIGURE 11-11 Coal-bearing cyclothems. Source: Harold Levin.
• FIGURE 11-12 Principal highland areas, southwestern part of the craton, Pennsylvanian time. Source: Harold Levin.
• FIGURE 11-13 The Pennsylvanian Period across eastern Colorado and New Mexico. Source: Harold Levin.
• FIGURE 11-15 Generalized cross-section through the Paradox basin
in Utah/Colorado. Source: After D.L. Baars et al., 1988, Basins of the Rocky Mountain region, in Sloss, L.L., ed.,
Sedimentary Cover of North American Craton. Geological Society of America.
• FIGURE 11-16 Division of the Permian Period into four stages in North America. Source: After P. B. King, 1948,
U.S. Geol. Survey, Professional Paper 215.
86