1. Precambrian Era Paleozoic Era Mesozoic Era Cenozoic Era
Geologic History
Precambrian Era
Paleozoic Era
Mesozoic Era
Cenozoic Era

2. Geology – science of the earth’s structure
Geologic Time – history of the earth from its formation 4.6 billion years ago to present
Era – a major geologic time lasting 10s to 100s of million of years.
Oldest Era to the Most Recent Era:
Precambrian
Paleozoic
Mesozoic
Cenozoic

3. Breaking Up Each Era
-each era is broken up into periods, named for the area where the rocks from the time period were first discovered

4. Videos Early History http://www.youtube.com/watch?v=-2YEJBK9yJM
First 5 mins only
Early Earth and Plate Tectonics

5. How old is the Earth? -Scientists cannot determine exactly
how old the Earth is
Why?
-They use rocks and Earth’s oldest rocks have been destroyed or recycled by plate tectonics
-The oldest rocks (4 billion years old) ever found were found in Canada near Great Slave Lake
How?
Radiometric Dating
-they use what’s called radioactive isotopes naturally occurring in rocks and minerals on the Earth

6. 4.6 BILLION YEARS Give or take a few million years
So, how old is the Earth?
4.6 BILLION YEARS
Give or take a few million years

7. Fill in the blanks on your handout
You will only need to write the TEXT that is in BLACK

8. Precambrian Era 4.6 billion to 570 million years ago (earliest life)
Canada-the land-chart 12
4.6 billion to 570 million years ago (earliest life)
areas of land and ocean developed and disappeared many times
the Canadian Shield was the first and largest landform in Canada
the rest of Canada formed hundreds of millions of years later
peaks of the Canadian Shield (mountains) were at one time 12,000m above sea level, NOW most peaks of the Canadian Shield are about 500m above sea level

9. Precambrian Era

10. Precambrian Era Mount Thule on Baffin Island
is the highest peak reaching over 1700 m high.
folding, faulting and erosion were responsible for the changes over the eras

11. What were the major geological and biological events of this era?
Canadian Shield formed
Life begins on Earth – age of single and multi celled organisms

12. Canada’s Landform Regions

14. Paleozoic Era 570 to 245 millions years ago
sediments were moved by rivers and deposited by shallow seas to surround the Canadian Shield
sediment is compressed to form sedimentary rock
North America (N.A.) was located by the equator during this time
Oil and gas deposits formed when N.A. was located here
Swamps turned into Coal mines in Nova Scotia
Pangaea formed 300 million years ago during this period

15. Pangaea

16. Pangaea

17. Paleozoic Era
in the beginning of the era the only living organisms were in the seas
at the end of the era there were plants and forests that began to develop
during the last 600 million years 5 mass extinctions occurred, the largest during this era where 80% of all sea life disappeared and animals/plants became extinct in large numbers
Do you think that Pangaea was the cause of this?

18. Major Geological and Biological Events:
this collision of the continents caused the formation of the Appalachian Mountains
Age of fish, insects and large swamps = coal
plants and animals on land

19. Mesozoic Era 245 to 66 million years ago
the beginning of this era is marked with the breaking up of the super continent Pangaea
at times seas and swamps covered much of Western Canada
while under water new layers of sedimentary rock formed on top of older rock
Coast Range Mtns. formed when tectonic forces caused the Pacific Plate and the N.A. Plate to collide
Rocky Mountains formed from tectonic forces folding

21. Mesozoic Era
Innuitian Mtns. formed as the N.A. plate moved north
climate was warm enough to sustain dinosaurs and reptiles in huge forests and swamps
Dinosaur Provincial Park in Alberta is where many dinosaurs bones were found because of the great inland sea that was located east of the Rocky Mountains
the end of this era was marked with another mass extinction, where 50% of animals became extinct
no one is absolutely sure of the cause

22. Major Geological and Biological Events:
Innuitian Mountains formed
Age of reptiles and dinosaurs, plants, birds

23. Dinosaur Provincial Park, Alberta

24. Mesozoic Era
Have you heard of possible reasons for this extinction?

25. Cenozoic Era
66 million yrs ago (present day, right now)
Canada’s landforms took their present shape so did all the other continents
mountains continue to form through folding, faulting and volcanoes - the Rocky Mountains formation completed
seas disappeared to form the Interior Plains
an ice age during the last 2 million years occurred covering a large portion of the Earth
huge masses of ice called glaciers moved across the earth like ‘giant bulldozers’ scraping and gouging the land they covered
How was Canada affected?

26. Major Geological and Biological Events:
Rocky Mountains and Western Cordillera formed and we had an Ice Age
Human beings developed and age of mammals

27. -large parts of NA covered by water -Appalachians formed
To get a better understanding of Geologic time, the 4 different eras and to discover what events occurred in each era
Cenozoic (1%)
-Rocky Mtns form
-ice sheets cover NA
Paleozoic (7%)
-large parts of NA covered by water
-Appalachians formed
Precambrian (88%)
-Shields formed
-Canadian, Brazilian,
African and Australian
Mesozoic (4%)
-water drops in NA
-Innuitian mtns form

28. Geologic Timeline Activity:
Instructions:
Read the front page of your activity handout.
Label the four major geologic eras at the bottom of your paper between the marked spots (the triangles). Put the name and years
Rank the major events on your handout from oldest to most recent
Put the 11 major events in order onto your timeline sheet from the oldest event to the most recent. Check them off as you add them to your timeline to avoid confusion.
Colour the four boxes in a different colour to represent the 4 geologic eras on the timeline

29. Geologic History - Paragraph
For Homework:
In 8 – 10 sentences
In your opinion, what era do you think is the most important in our geologic history? Explain why in detail.
Consider the events and life forms that were created during the eras