• Cenozoic (Current)
• Mesozoic (Mid)
• Paleozoic (Early)

• Cretaceous (Began 144 MYA)
• Jurassic (Began 208 MYA)
• Triassic (Begain 248 MYA)

• Lots of basalt (new oceans forming)
• Major climate changes (volcanic outgassing)

• Took place during the Triassic period
• N. America seperates from Gondwana and Africa
• Rifting, volcanism, normal faults, new Atlantic Ocean
• Mexico, S. America seperation

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• Took place in the early Jurassic period
• Africa and Antartica seperate
• Alot of basalt

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Phase 3:

• Took place during the late Jurassic - Cretaceous
• N. Atlantic Ocean widens
• S. America and Africa seperation
• Greenlan and N. America seperation

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• Increase in temperature difference between the poles and tropics

• Acceleration of oceanic and atmospheric currents; individual continents became less arid and human

• Late Cretaceous regression
• Sea level drop may have made the global conditions more arid
• Tethys Ocean closure began as Africa and India moved north (Eurasia)
• Deccan Traps in India, largest basalt deposit on earth

North American Events

What were major tectonic events that occurred during the Mesozoic Era?

• Absoraka sequence ends

• Zuni sequence begins and lasts early Jurassic - Cretaceous period

• Super plume beneath N. American craton increased spreading rates, sea level rises
• Zuni is the las epieric sea to completely cover the continent

E. North America

What were some important events that occurred in the Eastern Section of N. America?

• Erosion of the Appalachian Mountains
• Growth of the Atlantic Ocean

W. North America

The Moenkopi formation formed during the Zuni sequence.  What are the characteristics of the Moenkopi formation?

Moenkopi formation (early Triassic):

Shallow water, sandstone, shale, limestone, gypsum; mud cracks, ripple marks, amphipians, and reptiles

W. North America

Chinle formation was formed during the Zuni sequence.  What are the Chinle formation's characteristics?

• Late Triassic
• Petrified wood

W. North America

What are the characteristics of Navajo Sandstone?

W. North America

What are the characteristics of the Morrison formation?

• Mid Jurassic
• Deposited during Zuni transgression; 600k - sq mi
• Sandstone, siltstone, shale, conglomerate, great dinosaur fossils

Central North America

Important Zuni sequence rocks in Central North America include:

• Cretaceous limestone, black shale, and coal deposited in the Cretaceous Interior Seaway
• Similar deposit world wide (e.g. White Cliffs of Dover, England extensive chalk deposits)

E. North America

What were some geologic events happening in Eastern North America?

• Atlantic ocean grows
• Appalachian mountains erode
• Fault bound basins
• Newark group is the most significant: up to 6km thick, non-marine, arkosic sandstone, poorly sorted, dinosaur tracks
• Extensive basalt lava

Gulf of Mexico

What geologic events were happening in the Gulf of Mexico during the Mesozoic era?

• Gulf exented to its present day position during late Jurassic
• Extensive salt deposits
• Current subsidence today due to thermal cooling & weight of sediment
• Rudist reefs - bivalves that from high permeability Lst (Gulf Oil)

W. North America

What was happening within the Cordilleran?

• Lots of compression and deformation
• 4 Major orogenies
• Sonoma
• Nevadan
• Sevier
• Laramide

What is accretionary tectonics?

• Subduction
• Obduction=exotic terranes onto N. American continent 

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• Baholiths: lots of magma generated from easterly dipping subduction
• Franciscan Complex: deformed, chaotic mix of all 3 rock types; 7 km thick accretionary wedge

• Late Jurassic - Cretaceous (toward end of Nevadan orogeny)
• Subduction zone shallowed: igneous activity moved E
• Low angle thrust faults & N-D trending mountains

• Rocky Mountain Coal
• Persian Gulf Petroleum
• Gulf Coast Petroleum
• Uraniam deposits - Colorado Plateau
• South African Diamonds
• Gold deposits in Ca
• Copper belts

• Huge coral reefs
• Resurgence of marine invertebrates 
• Flower plants
• Dinosaurs
• Birds & Mammals
• Mass Extinction 

• What was the Mesozoic climate like?

• Warmer climates in Mesozoic, especially Jurassic & Cretaceous
• Extensive coal beds
• High latitude substropical plants

• Invertebrates became increasingly complex and diverse
• bivalves & echinoids (sea urchins, sand dollars)
• Scleractinian corals in shallow epieric seas
• Brachiopods diminish in abundance
• Age of the ammonites 

• Either straight or coiled cephalopods
• Most believed to be predators

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• Dominant reef organism w/one valve attached to the sea floor
• Jurassic-Cretaceous 
• More abundanct than corals in Tethys & Gulf of Mexico

• Modern amphibians (frogs)
• Cartilaginous fish abundant (sharks)
• Bony fish more complex

• Furry, warm-blooded, legs underneath, differentiated teeth, and altered jaw

• Dinosaurs
• Flying reptiles
• Crocodillians
• Marine reptiles

• Teeth in individual sockets - less likely to lose
• Single skull opening in front of eye modern have 2
• Include crocs, dinos, pterosaurs
• Triassic (arid H20 conservation) - recent

Saurischia

• Lizard-hipped
• Pelvic bones radiate in different directions from hip socket 
• Teeth all around jaws

Ornithischians were primarily plant eaters. What are some examples?

• Stegosaurs
• Anklyosaur
• Pachecephalosaur
• Hadrosaurs
• Iguanodon