Geologic History of Canada

1. Geologic History of Canada We estimate that the earth was formed over 4.6 billion years ago…

2. process erosion- Wearing away of the earth’s surface followed by the movement to other locations of materials that have worn away.

3. Other forces Collisions, folding, faulting Volcanic activity

4. fossils • The remains or impression of a plant or animal hardened in rock. • In general, prehistoric

6. History of the Earth* • The earth’s history can be divided into 4 time periods • The division of time into periods is called an era.

7. Eras Each era represents a period of sedimentary deposits and important movement of the earth Each era is marked by the formation of mountains and significant periods of extinction There are 4 eras

8. Precambrian era The oldest era Started at the moment the earth was formed Canadian Shield was the only part that existed At the beginning, the highest points (summits) of the Canadian Shield were 12 000 m above the sea!

9. What happened? Over thousands of year, mountains were gradually eroded and new ones formed. • Folding • Faulting • Volcanic Activity

10. Geological Event* The Canadian, Brazilian, African and Australian shields are formed

11. Biological Event • The first unicellular organisms and multicellular organisms appear • Ex) matter deposited by algae

12. Your turn! Pg 100, 1, 2a, 3

13. Rocks • How is an ______________ rock formed? • Igneus • Sedimentary • Metamorphic • The Canadian Shield is made up of all 3 rocks*

14. Rock Cycle

15. Rocks

16. Paleozoic Era* Characterized by Pangaea Formation =

17. Pangaea

18. Geological Events* Large parts of North America covered by seas Appalachians are formed Petroleum deposits formed

20. Biological Events* First appearance of plants and animals The time of amphibians and fish

22. extinction Distinction between The Paleozoic era and the Mesozoic era is marked by a mass extinction* 5 massive extinctions during this period The largest= near the end of the Palezoic era, 80% of sea life died, plants and animals disappeared*

23. Mesozoic Era Marked by the beginning of the separation of Pangaea Pangaea broke apart North American plate collided with South American plate Formation of Coast mountains= subduction + volcanic activity

24. Geological Events* Rockies formed Innuitians chains Process= folding

25. Biological Events* Era of the reptiles , ex) Dinosaurs First birds and mammals walk the earth

26. The end of the mesozoic era Marked by a major extinction, including dinosaurs The cause= uncertain Among many theories The “famous” asteroid colliding with the earth

28. Cenozoic Era* • Mountain chains in Western Canada continue to form(initiated by faulting, folding and volcanoes) • Glacial Period- 4 major Glacial Periods

29. Glaciation • Large masses of ice (glaciers) formed after the earth was lightly frozen…The effect was like a bulldozer that scraped and dug the earth. • The effect? • Traced the current contours of lakes, rivers, hills and plains

30. It’s cold!

31. Biological Event Mammals, including humans predominate

32. Geological Events Rockies fully formed Continents took their full form

33. Your turn