Forces that Shape Earth and Geological Time!

CGC1D- Canadian Geography

Planet Earth

1. Geologic History 1. Cenozoic (66 mya – present) 2. Mesozoic (245 -66 mya) Dinosaurs 3. Paleozoic (570 -245 mya) Ancient Life 4. Precambrian (4600 -570 mya) Earliest Life 2. Landforms 3. Rock Cycle

Earth’s Interior

Crust/Asthenosph ere

- 8-64 km thick - cold & fragile -Granite and - Basalt

Mantle

- 1800 km thick - hot & molten - Magnesium and Silicon

Outer Core

- 2000 km thick - 3 - 4000 ° C - liquid Nickel and Iron

Inner Core

- 1400 km thick - 5 - 6000 ° C

solid

Nickel and Iron

HYDROSPHERE Air ATMOSPHERE Water Land LITHOSPHERE

Geologic History

• Precambrian Era (Canadian Shield) Vulcanism Fault Ancient Sea Igneous Rock

1. Precambrian Canada #1 - The Canadian (also called the Precambrian) Shield • the geologic core of the country • ancient (4 billion years in some places), hard

igneous

rock from which all the other areas were created • used to be a huge mountain range

Precambriam

• Extensive volcanic activity folding/faulting and erosion – Intrusive / extrusive igneous rock – Cooling, creates Canadian Shield – Foundation of Canada’s landmass – Heat/Pressure (metamorphism) creates storehouse of Canada’s metallic mineral wealth – Surrounded by ancient sea

Geologic History

• Paleozoic Era (Shallow seas) Erosion Erosion Sediments Igneous Rock Sediment s

#2 - The surrounding series of plains or lowlands

• made of sedimentary rock • most of the sediments were eroded from the ancient Precambrian Shield • includes the Great Lakes - St. Lawrence Lowlands, the Interior Plains, the Hudson Bay Lowlands, and the Arctic Lowlands

Erosion

Transportation Transportation Deposition Deposition

Paleozoic con’t

• Extensive erosion, transportation (rivers), deposition of sediments from the Shield into adjacent seas • Compression of sediments in ancient seas create sedimentary rock • Today these sedimentary rocks form the bedrock for parts of every province • Organisms in seas form basis of oil/gas deposits in west • Swamps (tropical climate) create coal beds in east

Geologic History

• Late Paleozoic/ Early Mesozoic Era (Appalachians formed!) Erosion Sediments Igneous Rock Mountains Forming Sediments

Late Paleozoic, early Mesozoic!

• Creation of super-continent Pangaea folds/faults/uplifts Appalachian mountains in the east • NA is very tropical!

• Sediments keep on building up • Breakup of Pangaea as NA Plate moves West colliding with the Pacific Plate

Finally, Cenozoic era creates today’s mountain ranges…

#3 - The mountainous rim

• also made up of, in part sediments from the ancient Shield, also with metamorphic rock • unlike the flat lowland areas, the mountainous rim rocks have been uplifted by tectonic forces • there are three main mountain areas that make up the mountainous rim

• the Appalachian Mountains (the oldest and hence the lowest due to longer erosion) • the Innuitian Mountains of the very far north • the Western Cordillera (the youngest, and highest, is actually a series of several different ranges dominated by the famous Rocky Mountains, the most easterly of the Cordilleran ranges)

Geologic History

• Cenozoic Era (last 65 million years!)

4.

Sedimentary Mountains Eroding Mountains

2.

Sedimentary Forming Plains PACIFIC OCEAN ROCKY MOUNTAINS INTERIOR PLAINS

1.

Igneous Rock CANADIAN SHIELD APPALACHIAN MOUNTAINS

3.

ATLANTIC OCEAN

3. Mesozoic Canada Plate Collision 4. Cenozoic Canada Western Cordillera Glaciers !!! – ended about 20 000 years ago Appalachians Interior Plains Great Lakes St. Lawrence Lowlands Landforms not seen (in the back) Hudson Bay Lowlands , Arctic Lowlands , Innuitian Mountains

• Intrusive Volcanic / tectonic activity begin to uplift the Coastal Range • Tectonic forces uplift the Rockies/and as the plate rotates NW the Innuitian Mountains. (Arctic) • Dinosaurs roamed inland sea west of the Rockies (Red Deer Alberta) until extinction @ end of Mesosoic • Cenozoic: Rockies/Coastal Mntns. continue to form • Volcanic Activity create plateaus between Rockies and Coastal Ranges

Rock Cycle Videos

• • http://www.youtube.com/watch?v=K8dDq3 el_tQ&feature=related http://www.youtube.com/watch?v=EcfstbQ yrzU

Heats and melts

Rock Cycle

MAGMA Cools and hardens IGNEOUS METAMORPHIC Stresses or heats SEDIMENTARY Weathers, erodes, and deposits