Late Paleozoic Chapter
late Paleozoic was the time of forming the supercontinent Pangea.
and Baltica collided along a convergent plate boundary to form Laurasia during Silurian.
collision closed the Northern Iapetus
ocean and is called Caledonian orogeny.
Devonian Laurasia and Gondwana have started colliding as Southern Iapetus got
narrower. This orogen is called Acadian
tectonic events were in the Cordilleran, the Antler
orogeny, the Ellesmere orogeny
along the northern margin of Laurentia (collision between Laurentia and
Siberia). There was an other mountain range forming, the Uralian which marked the collision between Baltica and Siberia.
moved over the south pole, resulting extensive continental glaciation. indicated
by tillites. These icesheets spreaded and they well extended into the middle
temperate latitudes during max. glaciation.
advance and retreat of these glaciers resulted in global sea level changes, that
affected sedimentation patterns on the cratons.
moved north and collided with Laurasia, and it continued throughout the
collided with Kazakhstania and moved toward the Uralian margin of Laurasia
colliding with it during early Permian.
end of Carbonifeorus the various masses of the different continents were very
close to each other, and Pangea the supercontinent of the Phanerozoic began
is the time of formation of huge coal
deposits on the earth. Plants on the land;
assembly of Pangea was essentially concluded during the Permian with the
completition of many collisions (Hercynian, Alleghanian, Ouachita)
supercontinent was moving northward during the Permian. The enormous single
ocean is called Panthalassa, surrounded Pangea spanned from pole to pole. The
water in this ocean circulated more freely than at the present which resulted
more equal temperature.
condition!!!!! Because of the super continent. The fact of supercontinent
changed wind patterns, climate zones...... The climate pattern were troubled by
the newly formed mountains.
Paleozoic history of North America
boundary between Tippeccanoe and Kaskaskia sequence is marked by a major
the transgression of the Kaskaskia seawater in the early Devonian clean mature
sandstone covered much of the craton as basal depositis. (Oriskany sandstone,
NewYork, Pennsylvania). Their source area was the Appalachian mobile belt which
is contained older sandstone facies.
the sandstone basal sediment, the majority of kaskaskian rocks are carbonates
including reefs, and associated evaporite deposits. In many other areas of the
world same kind of sediments could be found. (England, Belgium, Central Europe,
Reefs in Western Canada
and Late Devonian reefs are very important in Western Canada (huge oil reservoar
By the middle Devonian they had a huge barrier reef arrangement and the lagoonal
areas behind them become restricted!!!!
Late Devonian the character of the sediment has changed from shallow water
carbonates to black shales and coarser detrital rocks. The source of these
sediments were the mountains formed by the Acadian orogeny in northern America.
Eastern Us. this black shale is
called Chattanooga shale. These shale deposits are the best developed along the
Appalachian mobil belt to the Mississippi valley, they can be found elsewhere
This shale usually thin bedded, non calcareous, less than 10 m thick, and
rich in land plants. They sometimes are
bitominous, containing mostly degraded algal material. (Source material for
Presence of black shale indicate anaerobic bottom condition, reduced
supply of coarse sediment and high organic productivity of the overlying
oxigenated water layer.
the black shale formation, during Late Devonian early Mississippian, the
carbonate deposition returned. Crinoideal limestone, oolitic limestone, dolomite
were common. These carbonates display cross-bedding, ripple marks, and well
sorted fossil fragments, all of which indicate shallow marine environment.
the Late Mississippian regression of Kaskaskia sea from the craton resulted in
deposition of detrital sedimentary rocks. Sandstone in the Illinois basin,
(petroleum reservoar). These detrital sediments were followed by an unconformity
because of the ongoing regression.
includes uppermost Missisipian through Lower Jurassic rocks. The big unconformities between Kaskaskia abd Absaroka divides
the Carboniferous into the Mississippian and Pennsylvanian sequence. These two
system are equivalent to the Europian lower and upper Carboniferous.
sequence contains a little bit different rocks, than what is characteristic to
those in the Kaskaskia sequence.
have a well developed foreland basin, behind the Caledonian, Acadian highland
which is very deep fast subsiding basin on its east side, and become gentle
sloping on its west side.
in the foreland basin
Nonmarine detrital rocks with coal deposits on the east (Pennsilvanian cyclothems)
marine detrital rocks and limestone on the west
The Pennsylvanian rock are characterized by cylical pattern. The cycles
are alternating marine and nonmarine deltaic strata. (the formation of the cycles is the result of small scale sea level changes along the
Nonmarine unit:deltaic, fluvial sediment
clay, coal (accumulation of plant material) transgressive
Marine unit of limestone and shale with marine fauna.
Modern examples for this:
cratons are stable areas, in the Pennsylvanian period, there was some unusual
deformation in the American craton and resulted in uplift and big part of the
Precambrian rocks exposed. During this deformation arches and domes formed, and
some older highlands became activated such as the Cincinnati arch, Nashwille
dome, and Ozark dome.During
the late Absaroka the area of greatest deformation was the southwestern part of
North-America, where fault-bounded uplifted blocks formed the Ancestral rockies.
As these mountains were uplifted and became source of large scale
erosion, huge amount of coarse grained red arkosic sandstone and conglomerate
were deposited in the surrounding basins. (Colorado Springs beautiful red
sandstone, Denver’s red sandstones).
various basins bordering the ancestral Rockies contain extensive marine and
basin and the four corners region (Arizona, New Mexico, Colorado, Utah) was
covered by the Absaroka sea. During the Middle Pennsylvanian thick cyclical
deposits of gypsum, anhydrite and salt formed in the central basin area.
Fossiliferous and oolitic limestones were deposited around the perimeter,
with patch and barrier reefs grew along the western margin, further restricting
the central basin. (oil reservoar).
the Late Pennsylvanian, the whole Paradox basin was filled, by arkosic red
Absaroka sea started to retreat, it wes restricted to West Texas and Southern
New Mexico, forming a complex of lagoonal, reef and open shelf environments.
reefs grew around the basin margins. While limestones, evaporites and red beds
were deposited behind the reefs in the lagoonal areas.
Mountains of Texas and New Mexico where the Capitan limestone formed.
end of the Permian the Absaroka sea had retreated from the craton leaving
continental red beds over most of it.
late Proterozoic and early Paleozoic this belt was passive continental margin
along which extensive continental shelf sediments were deposited.
in the Middle Paleozoic an island arc (Klamath arc) formed on the western margin
of the craton.
the Late Devonian, early Mississippian there was a collision between this
eastward moving island arc and the western border of the craton. As a result a
highland have formed. This orogenic event is
the so called Antler orogeny.
highland produced lots of sediment that were deposited toward the east
in an epiric sea covering the craton, and to the west into a deep sea.
was also a passive margin, which became active convergent margin during the
Mississippian. Volcanic arc to craton subduction hapeened to the south. Rapid
sedimentation produced clastic vedge, which thickened to the south. 16,000 m of
Mississippian and Pennsylvanian aged rocks crops out in the Ouachita mountains
representing the really rapid sedimentation rate of this time. The collision of
Gondwana and Laurasia is marked by a big mountain range.
cratonic uplift most likely is also related to this compressional force.
mobile belt extends along the western border of Baltica.
the Middle Ordovician, subduction along the boundary between Iapetus plate and
most extensive phase of the Caledonian orogeny occured during the Late Silurian
and Early Devonian with the formation of mountain range along the margin of
Baltica. Red colored sediments deposited along the front of the Caledonian
high-land forming a large clastic vedge. Old Red Sandstone.
Acadian orogeny occured along an oceanic continental convergent plate boundary,
and later during the Devonian Baltica finally collided with Laurentia forming a
continental-continental convergent plate boundary along zone of collision.
was longer and more intensive, than Taconian. 360-400 million years ago.
and weathering of the Acadian highland produced a very thick clastic vedge,
called Catskill delta. These sediments are composed of red, coarse
conglomerates, sandstone, and shale, with much more sediment then the queenston
the west the red beds grade laterally into gray sandstones and shales containing
fossil tree trunk, which indicate marsh and swampy environment.
the collision of eastern Laurasia with Gondwana.
collision began during Mississippian. The greatest deformation occured during
Pennsylvanian and Permian. (Hercinian orogeny). The central and southern part of
the Appalachian mobile belt were folded and thrust toward the craton as eastern
Laurasia and Gondwana were sutured (Alleghanian orogeny)
orogenesis represent the final joining of the supercontinent Pangea during Permian.
Devonian to Permian rocks (Michigan basin, Illinois basin, Williston basin of
Montana, South Dakota)
reefs in the western US. Texas also important.
and mid western US.
coal more than 80% C)
the coal is metamorphosed and become antracite 98%C.
evaporites in Europe
Virginia, Maryland, Pennsylvania.
and it is found everywhere
type lead and zink deposits in Missouri, Virginia, Tenessee.