LAND BUILDING - TECTONIC PLATES
Influence of Physical Environment on Canadians
Interaction of Canadians with their physical environment.
Theory of Continental Drift
Proposed by Alfred Wegener; continents were joined as Pangaea 225-250 million years ago.
Continents drifted apart due to this process.
Wegener first used the term "Continental Drift".
Evidence for Continental Drift
Geological similarities in Africa and South America.
Age discrepancies between older and younger rocks.
Fossil distribution across continents.
Limitations of Continental Drift Theory
Lack of explanation for mechanisms behind plate movement; led to skepticism.
Plate Tectonics
Describes the structure and movement of Earth's crust.
Tectonic plates as pieces of the crust.
Physical Processes Contributing to Diversity in Canada
Constant changes from tectonic movements, erosion, and deposition shape land features.
Plate Boundaries and Interactions
Tectonic plates interact in three ways:
Divergent
Convergent
Transform/Sliding
Each interaction leads to different geological features (e.g., trenches, volcanoes).
Convection Currents
Large systems in the mantle that drive plate movement like a conveyor belt.
Heat distribution causes cold rock to sink and hot rock to rise, influencing tectonic activity.