Presentation on theme: "Glaciers Carve Land and Move Sediments"— Presentation transcript:
1 Glaciers Carve Land and Move Sediments Section 5.4
2 Explore Glaciers pg 165What happened when the ice cube was dragged across the clay?What happened to the sand and gravel in the ice cube as it melted?
3 Extent of Glaciers Glaciers are In mountain ranges around the world In land regions at North Pole and South Pole10% of Earth’s surface TODAYUsed to be 30% 30,000 years ago
4 2 Types of Glaciers Alpine Glaciers Called valley glaciers Can cause a V shaped mountain valley to become a U shaped valleyIf an alpine glaciers flows into an ocean, blocks can break off and form an iceberg!Continental GlaciersCalled ice sheetsCover GreenlandCover Antarctica
5 2 Types of Glaciers..continued Where do each of the two types of glaciers form?Alpine glaciers form in mountains and flow into valleys.Continental glaciers form on large landmasses (continents) near the poles (North/South).
6 Glacier= large mass of ice that moves over land Alpine Glacier …what are the dark lines?These are rocks picked up by the glacier along its route.Continental Glacier
7 Why are the cracks shown near the surface of the glacier and not at the bottom? At the bottom…. The ice is under so much pressure that it flows instead of cracking….not as much pressure on the top so it cracks.
8 How is an alpine glacier like a plow? The glacierScoops up rock and soilPicks rocks from the sides of valleysSediment moves with it
9 What’s left behind?Till= the sediment left on the ground by a retreating glacier.Moraine= a deposit or hill of tillAND……..Moraine at Mono Lake, California, United States
10 What’s left behind?Kettle Lakes= bowl depression that was once filled in with ice that has melted after the glacier retreated.
11 Section Review page 1701. List 2 processes that cause glaciers to move.GravityWater making the bottom slippery will cause flowing and sliding
12 Section Review page 1702. What are the two major types of glaciers and where are they found?Alpine and found in mountain valleysContinental and found in Antarctica and Greenland
13 Section Review page 1703. Describe the land features left behind by glaciers that have melted and shrunk.Glaciers leaveU-shaped valleysMorainesAbrasionsTillKettle lakes
14 Section Review page 1704. Identify two ways in which the erosion effects of glaciers differ from those of rivers.a. Glaciers crush and move large rocksRivers move smaller sedimentsb. Glaciers pile up moraines, etcRivers create sandbars, meanders, and deltas
15 Section Review page 1705. How would glaciers be affected by changes in climate, such as global warming and global cooling?Warming melts glaciers and shrinks ice sheets (continental glaciers)Cooling causes glaciers to expand and form in new places.
16 Section Review page 1706. Regions near the equator are generally the warmest on Earth. However, in one small area of Africa, there are glaciers close to the equator. Form a hypothesis to explain why these glaciers exist.16IF there are glaciers in Africa near the equator,THEN they are in the high mountainsBECAUSE high mountains could be cold enough for glaciers.