Effects of Glaciation

Effects of Glaciation

• Alpine glaciers originate in mountainous regions, like the Rockies.
• Snow accumulates in mountain basins called cirques.
• Snow compacts into ice and flows downhill due to gravity forming a glacier.
• Glaciers erode the surrounding rock by picking up rocks and moving them.
• The ice deepens cirques.
• When two cirques meet, they form arêtes, knife-edge ridges.
• Multiple cirques create pyramidal peaks called horns.
• Glaciers carve U-shaped valleys.
• Tributary valleys are often left as hanging valleys.
• Glacial meltwater creates long, narrow inlets called fjords.

Continental Glaciation

• Continental glaciers shape landscapes.
• They deepen valleys and create lakes.
• Glaciers erode vast amounts of soil, sand, gravel, and rock.
• Glacial till (clay, sand, gravel) is deposited by ice sheets.
• Moraines are ridges or piles of till (deposited by ice sheets).
• Glacial rivers flow beneath the ice sheet, depositing sand and gravel in features like eskers.
• Eskers are steep-sided ridges.
• Drumlins are oval-shaped hills of glacial till.
• Kettle lakes form when chunks of ice melt within till deposits.

Benefits of Glaciation in Ontario

• Glaciers carved the Great Lakes, useful for transportation, agriculture, and industry.
• Flattened landscapes are good for farming and cities.
• Glaciers carved valleys and lakes, creating destinations.
• Glaciers create deep soil.
• Glaciers leave deposits of sand and gravel, useful for construction.
• The Oakridges Moraine is a protected area with diverse wildlife, recreational activities, and clean water.