World Geography 3200/3202 October 2010 Erosion & Glaciers World Geography 3200/3202 October 2010

Glaciers Introduction In this lesson you will: 1.4.1 Define the terms outwash plain, terminal moraine, erratic, drumlin, and esker. (k) 1.4.2 Examine evidence for the direction of movement of a continental glacier. (a) 1.4.3 Define the terms cirque, arête, hanging valley, lateral moraine, and terminal moraine. (k) 1.4.4 Define the term fiord. (k)

Continental vs. Alpine Continental glaciers : Glaciers that cover parts of continental land masses like Greenland & Antarctica Alpine glaciers : Glaciers that are found high in mountain valleys, above the snow-line

Glaciers of the world Continental glaciers Alpine Glaciers

Continental Glaciers= 1.6.1 Distinguish between the terms alpine glaciation and continental glaciation. (P.32) Alpine Glaciers = form high in mountain valleys above the snow-line Continental Glaciers= cover parts of continental land masses near poles; eg Greenland & Antarctica

Alpine Glaciers Alpine glaciers are like very slow moving rivers of ice flowing down high mountain valleys They typically erode the mountain beneath them into a u-shaped valley with steep sides. Some alpine or valley glaciers are 1000m thick and up to 160 km long, though most are only a few km in length.

Continental vs. Alpine: Differences Location; Alpine glaciers are only found on mountain tops whereas continental glaciers are only found at the earth's poles regardless of elevation. Size; Alpine glaciers are smaller compared to Continental glaciers.

Continental vs. Alpine: Similarities Both move and cause erosion (gravity & friction) Both change the landscape by weathering & deposition Both create land forms Both developed in constantly cold temperatures below freezing. (< 0)

Features of Continental Glaciers

Features of Continental Glaciers Use your textbook to create profiles of the following concepts related to continental glaciers outwash plain terminal moraine Erratic Drumlin esker

Features of Alpine Glaciers

Features of Alpine Glaciers Use your textbook to create profiles of the following concepts related to alpine glaciers Cirque Arête hanging valley lateral moraine terminal moraine fiord

Evidence of Glacier Movement The gently-sloped end of drumlins point in the direction of glacier movement. The terminal moraine marks the furthest extent of the glacier. The layers of silt in an outwash plain can indicate direction of glacier movement. (fine particles would be at the leading edge while larger particles would have been closer to the glacier)

Continental Review Questions Where are continental glaciers found? THE POLES OF EARTH Where are alpine glaciers found? HIGH IN MOUNTAIN VALLEYS Many land forms are created by continental glaciers. Which one is very similar to a river delta? OUTWASH PLAIN Many land forms are created by continental glaciers. Which one is created by a river running under the glacier? ESKERS

Continental Review Questions Many land forms are created by continental glaciers. Which one is a large boulder that looks out of place in its surroundings? ERRATICS Many land forms are created by continental glaciers. Which one marks the furthest extent of the glaciers movement? TERMINAL MORAINE Many land forms are created by continental glaciers. Which one is an egg-shaped hill? DRUMLIN Which end of a drumlin indicates the direction of glacier motion? POINTY

Review Questions What alpine glaciation feature consists of a circular hollow cut into the bedrock. CIRQUE What alpine glaciation feature consists of a knife-like edge between adjacent cirques? ARETE What alpine glaciation feature consists of a valley that abruptly ends as the main valley is at a much lower level? HANGING VALLEY What alpine glaciation feature consists of deposits along the side of the glacier. LATERAL MORAINE What alpine glaciation feature is formed when a valley glacier reaches the ocean and eventually melts back. FJIORD