1. Mesozoic Era (Age of the Dinosaurs)
Three Periods
Triassic
Jurassic
Cretaceous

2. MESOZOIC ERA KNOWN AS THE MIDDLE ERA
TIMEFRAME: Occurred between 248 to 65 million years ago

3. IMPORTANT EVENT Time marked by rapid movements of plates
A major geologic event of the Mesozoic was the break-up of the super continent of Pangaea into several large continents.
HAD WARM CLIMATE

4. Mesozoic Era Triassic Period (225-180 MYA)
Pangaea (supercontinent) existed

5. PANGAEA

6. LAND (GEOLOGICAL) FEATURES THAT FIRST APPEARE:

7. Mesozoic Era Cretaceous Period (135-65 MYA)
Flower plants CALLED (angiosperms) 1ST APPEARED

8. ANIMALS/ORGANISMS (BIOLOGICAL) FEATURES THAT FIRST APPEARED:

9. Mesozoic Era Triassic Period (225-180 MYA)
First Dinosaurs (small in size)
Pisanosaurus
Length:3 feet Height:1 foot Weight:15 pounds
Eoraptor:
Length:3 feet Height: 1 foot Weight:20 pounds

11. Mesozoic Era Jurassic Period (180-135 MYA)
Pangaea starts to separate

12. Mesozoic Era Jurassic Period (180-135 MYA)
1st mammals (small rodents).

13. Mesozoic Era Jurassic Period (180-135 MYA)
1st birds (Archaeopteryx).
Jaws and bone structure like dinosaurs
Bones are hollow, like birds
Had feathers

14. Mesozoic Era Jurassic Period (180-135 MYA)
Reptiles in the sea - Icthyosaurs – 8 m; Plesiosaurs – 15 m.

15. ANIMALS/ORGANISMS (BIOLOGICAL) & GEOLOGICAL FEATURES THAT BECAME DOMINANT

16. Mesozoic Era Jurassic Period (180-135 MYA)
Dinosaurs BECAME DOMINANT

17. Mesozoic Era Cretaceous Period (135-65 MYA)

18. Mesozoic Era Cretaceous Period (135-65 MYA)
Continents in modern positions

19. Mesozoic Era Triassic Period (225-180 MYA)
GYMNOSPERMS BECAME DOMINANT

20. WHAT CATASTROPHIC EVENT CAUSED THE MASS EXTINCTION?

21. MASS EXTINCTION
Asteroids, METEORITE, or Comets collided into the Earth AND CAUSED Mass Extinction

22. How could a meteorite impact cause a mass extinction?
The impact caused shock waves, tidal waves, and sent a tremendous amount of dust into the atmosphere
As the dust re-entered the Earth’s atmosphere, it would have instantly heated the atmosphere causing tremendous forest fires
Dust from impact blocked out the sun and caused major climate change and plants to die
Plants, animals, etc. went extinct due to the climate changes and competition between organisms

23. Mesozoic Era Cretaceous Period (135-65 MYA)
Mass Extinction: 50% of all plant and animal groups die out
Alvarez’s Meteor Impact Theory- 10 km wide meteorite hits Earth

24. Scientists now have fresh evidence that such a cosmic impact ended the age of dinosaurs near what is now the town of Chixculub in Mexico.

25. Mesozoic Era Cretaceous Period (135-65 MYA)
Evidence of Impact: Iridium
An element that is very rare in Earth rocks and very common in meteorites
The layer of rocks above the last dinosaur bones contain ~ 160x normal levels of iridium
Called the K/T Boundary