(245-66 million years ago)
divided into three periods
37 million years (Mountains in Germany)
64 (Jura mountains in Switzerland)
78 million years (Paris basin France)
Mesozoic the major event was the break up
of the supercontinent Pangea.
course very much influenced the climate, and the ocean currents, of course
the evolution of life was also influenced. Populations became separated
or were brought into contact giving rise to lots of evolutionaly possibilites.
most commonly is called the age of “Dynosaurs” or Reptiles, it was also the
time for the evolution of birds, mammals and angiosperms (flowering plants).
up of Pangea
of the new Wilson cycle the supercontinent started to breake up almost as soon
as it got together.
break up has four general stages.
between Laurasia and Gondwana during the Late Triassic.
end of the Triassic the expanding Atlantic Ocean had separated North America
from Africa. This was followed by
the rifting of North America from South America during Late triassic, Early
of Tethys and Pacific, and Pacific ocean waters flowed into the new forming Gulf
of Mexico. (low latitude, arid climate lots of evaporite!!!)
and movement of the various Gondwana continents during Late Triassic, Early
Jurassic periods. As early as the Late Triassic, Antarctica and Australia
separated from South America and Africa, while India split away from all
Gondwana continents and began to move northward.
Jurassic South America and Africa began to separate.
basins have been formed and thick evaporates developed.
this stage the Tethys seaway began to close as a result of clockwise rotation of
Laurasia and the northward movement of Africa, ---- Mediterranean sea. By the
end of Late Cretaceous Australia and Antarctica had separated, India riched the
equator, South America and Africa were widely separated, and Greenland started
to separate from Europe.
sealevel rise happened in the Cretaceous. Uniqe conditions again.
happened during Cenozoic, Australia moved northward and Greenland completely
separated from Europe and rifted from north America to form a separate land
of the breakup on the climate
of the Pangea!!!!! Megamonsoon
continental landmasses. Temperate climate only at high latitude. Triassic is ice-free,
therefore the temperature gradient is small.
break up caused larger temperature gradient, cooling toward the Jurassic.
However, the general climate remained warm, bec. there were no continents at the
The Triassic essentially is the same as the Permian. Red beds are
wide spreaded on the caton and in the Appalachian, Greenland region.
continental area remained very large, sea level was still low, and rivers
carried sandstone to the bordering seaways.
Along the eastern and southern margin as the biginning of the break up of
Pangea, normal faulting and igneous activity had started. The faulting started
during the Late Triassic, and continued into the Jurassic.
Marine deposition was continuous over much of the Cordilleran region,
however the island arc continued to collide with the craton during the Triassic.
This activity is called Sonoma orogeny. During the Jurassic the whole
Cordilleran region has experienced a serious of mountain forming episodes that
resulted in the formation of the Sierra Nevada and the Rocky Mountains. The
entire mountain building event is called Cordilleran orogeny.
the Mesozoic most of the craton was well above the sea level and did not
experience epiric sea indunation. However the Triassic and early Jurassic period
still belong to the Absaroka sequence. The next cratonic sequence is called Zuni
and we will incorporated its sediments into the three continental margin
the Early and Middle Triassic coarse detrital sediments derived from the erosion
of the newly rised Appalachian filled the different intramountain basins. The
erosion of the Appalachian almost completely finished, by the end of the
the Late Triassic the first stage of the Pangean breakup resulted in the
formation fault block basins from Nova Scotia to North Carolina.
the chain of rift basin block faulted mountains gave source for the huge amount
sediment in this basin. 6000 m of immature, coarse grained detrital sediment
accumulated here preserve the best climate induced cyclicity in the whole earth
name of the whole rift basin sedimentation is Newark Supergroup. The basins are
clearly freshwater basins, and they contain lots of evaporite, lots of important
fossils, Dinosaur footsteps.
with the sediment wide basalt lava flows blanketed the basin floors. Formation
of basalt sills and dykes also important. The most famous basalt sill is the so
called Palisades sill (200 million years old) along the Hudson river in New
York-New Yersey area.
Atlantic ocean started to grew the rifting ceased along the eastern marging
which finally became a passive margin. The block faulted mountains formed during
the rifting continued to be the source of detrital sediment filling up the ocean
basin of the newly forming Atlantic ocean.
the Cretaceous the Appalachian mountain reelevated again and shed sediment onto
the continental shelf, forming a gently dipping seaward thickening wedge
of rocks up to 300m thick. These rocks today exposed in a belt expending
from Long Island toNewYork, to Georgia.
area was above the sea level until the Late Triassic, when the Gulf of Mexico
began to form as the result of breaking up of North America and South America.
Some oceanic water flew into this narrow, restricted basin and with arid
continental climate it produced huge amount of evaporite. More than 1000 m of
evaporite has formed. (These evaporites made it possible to study the great salt
dome tectonism during Tertiary, which associeted with great oil formation).
the late Jurassic the basin was not that much restricted, and evaporite
deposition ended. Normal marine condition has returned and cyclic deposition of
sandstone, shale and limestone started.
the early Cretaceous the area was experienced transgression and deep marine wter
covered this region during the rest of the Cretaceous.
forming became characteristing for this area during the Cretaceous.
reefs during the Cretaceous were different from the Jurassic ones. During the
Cretaceous the major reef builders are Bivalves called Rudists. These reef are
also excellent oil reservoirs, because of their high porosity. (Texas)
the Early Triassic the island arc collided with the continent forming an oceanic
continent convergent boundary. The tectonic event is called Sonoma orogeny. The
subduction here was steep and fast in response of the westward moving craton as
the Atlantic ocean was opening up. During these tectonic event the
sedimentationof this region consisted of shallow marine sandstone, shale and
limestone. During the Late Triassic the regression of the sea brought even lower
sea level, so the exposed areas of the former seafloor experienced erosion.
During this time over this region red sandstone which are as spectacular as the
ones from Permian in the Painted desert in Western North America.
the most famous Triassic Formation of the western margin Triassic is the Late
Triassic Chinle Formation widely exposed over the Colorado Plateau spectacularly
exposed in Petrified Forest National Park, Arizona. (Conifers (Gymnosperms).
Fossilization resulted here from the silification of plant tissues. The Chinle
Formation also famous about the Labirinthoid amphibians, phytosaurus, and small
Cretaceous Cordilleran tectonism
very complex. Its name is Cordilleran orogeny. The tectonic activity started
during the Jurassic and continued into the Cenozoic. Most of this activity
related to the westward movic North American continent. The orogeny has three
began during the Late Jurassic and continued into the Cretaceous.
this phase the major event is the generation of large amount
grenite-granodiorite magma (huge batoliths of Sierran Nevada, Idaho, Southern
California, Coast Range.
happened mostly in the Cretaceous. The major event of this phase was the
formation of low angle thrust faults as a result of the subduction of the
pacific plate beneath the North American plate. This thrusting produced north to
south trending mountain ranges consisting blocks of the paleozoic shelf and
slope strata.Southern California-Utah and from Montana to Western Canada.
Cretaceous, early Cenozoic, east of the Sevier orogenic belt in the present day
Rocky Mountain areas of New Mexico, Colorado and Wyoming.
this phase there were some thrust faulting, but more commonly folding has
occured. As a result anticlines, domes and basins formed in the Middle and
sediment in the Western region of North America during the Early Jurassic was
clean, crossbedded sandstone, indicative of windblown deposits.
thickest and most prominent of this is the Navajo
Sandstone (Zion National Park, Utah). The most fantasting pattern of this
sandstone is the large scale cross beds, some of which are more than 25 m high.
The upper part of the sandstone has smaller cross beds and contain Dynosaur and
Crocodilian fossils. Based on its features it is most probably represent a
coastal dune environment.
the Middle Jurassic a transgression happened Sundance
sediments accumulating from the closeby highlands.
the regression of Sundance sea, the area was covered by multicolored sandstone
called Morrison Formation. Morrison Formation represent continental lake
environment, which cyclically dried out having just a few stream. The Morrison
Formation is world famous, because it contains a very rich dynosaur fauna.
Minimum of 50 individuals have been found in a small flood plain area along
stream beds. The amount of skeletons indicate, that they were brought together
during floods (Dynosaur National Monument Vernal, Utah).
the Late Cretaceous a big marine transgression
happened Cretaceous Interior seaway, that occupied the area east of the
Sevier orogenic belt. This seaway is more than 1500 km wide and it effectively
divided North America into two large land masses until just before the end of
margin did not have more than 100 m thickdeposit, indicating, that sucduction
was very low. On the west however, lots of sediment formed from the erosion of
the newly uplifted mountains; congl. sandstone, siltst. shale, depending on the
small scale sealevel changes.
building, and continental accretion not only possible by partial melting along
subduction zones. Geologists discovered, that parts of mountains formed by
accretion of small lithospheric blocks, that are clearly foregin in origin.
evidence indicates that at least 25% of the entire
Pacific coast from Alaska to Baja California consists of accreted
are composed of island arc, oceanic plates, and small fragments of continents.
The growth by microplates are faster along active margin, than passive ones.
lignite and bituminous coal, with some local antracite
russia, China, Hungary
Triassic, Jurassic sandstone