Ch 14 Mesozoic

1

• Ch 14 Mesozoic
• Triassic
• Jurassic
• Cretaceous

Movie end of Permian http//www.pbs.org/wgbh/evo
lution/library/03/2/l_032_02.html
2
Breakup of Pangaea
3
Columnar jointing of basalt, Palisades Sill, New
York
4
(No Transcript)
5
Fig. 14.6
6
Sandstones and shales filling Newark Aulacogen,
New Jersey, Triassic
7
Non-marine and marine rift valleys
Evaporites later trapped petroleum
8
Fig. 14.9a
Typical redbed Triassic-Jurassic sequence,
Wyoming, Triassic red Chinle Formation under
Navajo Formation
9
Dry periods left gypsum from dry lakes, Spearfish
Formation, Black Hills, South Dakota, Triassic
10
Late Triassic Paleogeography
11
Cross-bedding, Navajo Sandstone, Zion National
Park, Utah dunes 300 ft high
12
Current sand deposition in Namibian Desert,
southwest Africa (photo inverted for comparison
with North America)
13
Fig. 14.12
Early Jurassic Paleogeography
14
Zuni
You are here!
Absaroka

• Six major sequences bounded by unconformities
• Sea level change
• Extinction event

Kaskaskia
Tippecanoe
Sauk
15
Late Jurassic Paleogeography
16
Cordillera formation
17

• Terranes in the Cordillera and Asia
• Suspect
• Exotic
• Fossils
• Paleomagnetism
• Stratigraphy
• Igneous rocks

18
Stikinia Wrangellia
19
Fig. 14.19
Limestone and shale over basalt, Wrangellia
terrane, Wrangell Mountains, Alaska
20
Mississippian to Jurassic Development of
Cordillera
21

• Model for Cordillera
• Andes Mountains
• Trench
• Accretionary prism
• mélange
• Forearc basin
• Volcano arc
• Foreland Basin

22
Botholiths emplaced in cordillera during Mesozoic
23
Fig. 14.25a
Dinosaur fossils at Dinosaur National Monument,
Utah Morrison Formation, Jurassic

• Morrison Formation

24
Cretaceous East-west cross-section of foreland
basin east of Cordillera
25
From eastBackarc basin - Nevada and
UtahVolcanic arc - Sierra Nevada
MountainsForearc basin - Great Valley Group
Central Valley, CaliforniaAcrretionary prism
- Franciscan Melange
26
Franciscan Melange, San Simion, California
27
Fig. 14.29b
Pillow lava of ophiolite, Oregon
28
Fig. 14.29c
Marine shales and turbidite sandstones, San
Francisco, California probably deposited in
forearc basin, Cretaceous
29
Conglomerate, Canyon State Park, Utah, Cretaceous
probably deposited on alluvial fans during
Sevier orogeny
30
Simplified cross-section through Canadian Rocky
Mountains Sevier Orogeny 80 mya
31
Fig. 14.32

• Laramide orogeny
• Gentle subduction angle
• Magmatic null
• Deep rock was folded and thrust upward
• Volcanic arcs to north and south

32
Middle Cretateous Paleogeography
33
Chalk of Niobra Formation, Kansas, Cretaceous
34
Fig. 14.33b
Interfingered shale and sandstone indicating
transgressing and regressing coastline, Utah,
Cretaceous
Alternating coal and sandstone indicating
transgressing and regressing swampy shore, Utah,
Cretaceous
35
Late Cretaceous Paleoclimate
36

• Black organic shales
• Increased organic carbon
• Decreased marine

37

• Mesozoic Ocean
• Coral
• Scleractinian coral
• Sponges
• Cephalopods (mollusks)
• Ammonites, belemnites
• Crustacians
• Lobsters, crabs
• Mollusks
• Fish, sharks, rays
• Teleost

• Marine reptiles
• Placodonts
• Plesiosaurs
• Ichthyosaurs
• Marine turtles
• Mososaurs
• Echinoderms
• Phytoplankton
• Coccolithophores
• Zooplankton
• Foraminifera

38
Belemnites
39
Fig. 14.41
Coccolith calcareous shell from Coccolithophore,
phytoplankton
40

• Land
• Archosaurs
• Crocodiles
• Phytosaurs
• Dinosaurs
• Birds

41

• Dinosaurs
• Saursichian
• Sauropod
• Theropod
• Birds
• Ornithischian

42

• Evolution of dinosaurs to birds
• Archaeopteryx
• Skull, long tail, hind limbs, and wrist and ankle
  like small dinosaur
• Wishbone, long fingers and feathers like bird

43
(No Transcript)
44

• Amphibian
• Frogs, salamanders, turtles, lizards, snakes
• Mammals
• Marsupials
• Placental

45
End of Mesozoic - Extinction
46
(No Transcript)