Chapter 17

Card Set Information

Chapter 17
2012-06-07 22:08:02

Glacial and Periglacial Processes and Landforms
Show Answers:

  1. How many major continental ice sheets were there in the ice age? Where were they?
    There were four. They were located in Greenland, Antartica, North America, and Northern Europe.
  2. Which ice caps still remain?
    Greenland's and Antartica's.
  3. How far did the North American ice sheet extend? What did the North American ice sheet create?
    It extended to New York, and created the Great Lakes.
  4. In what direction do ice plates move?
  5. Manhattan exists due to ______ activity.
  6. There were _____ major glacial advances during the ice age. There were also glacial _____. Ice age was a period of __________.
    Four. Retreats. Oscillation.
  7. What are the reasons for climate change?
    Axial tilt, rotational wobble (Milankovitch cycles), and volcanic eruptions.
  8. What is an alpine/ mountain valley glacier?
    A glacier that starts out appearing only seasonally. After some time, some of the snow that doesn't melt begins to accumulate past the normal seasons.
  9. Define firn.
    Compact ice and snow.
  10. Define cirque. How are they created?
    Cirques are bow-shaped depressions. They are created as gravity pulls on the ice, which tugs on the rock.
  11. What is a glacial horn?
    A pyramidal peak that results when several cirque glaciers gourge an individual summit from all sides.
  12. What is an arete?
    A sawtooth ridge that has been carved by glacier on two sides.
  13. What is a fjord? How is it created?
    long, narrow, deep inlet of the sea between high cliffs. They are typically formed by submergence of a glaciated valley.
  14. What is a zone of accumulation?
    The zone where ice and snow build up over time.
  15. What is a zone of ablation?
    Zone where ice and snow melts.
  16. Define till.
    Material that a glacier is carrying ( boulders, sand, pebbles)
  17. What is morraine?
    Glacial till deposits.
  18. Define esker.
    A sinuously carving, narrow ridge of coarse sand and gravel.
  19. What is an outwash plain?
    The area of stratified drift beyond morrainal deposits that features channels that are meltwater-fed, braided, and overloaded with sorted and deposited materials.
  20. What is kettle? How is it formed?
    A steep-sided hole that frequently fills with water. It forms when an isolated block of ice remains in a ground morraine , outwash plain, or valley floor, accumulates material around it as it melts.
  21. What is loess? How does it form?
    Glacial silt. It was carved and ground up by glaciers, washed away and then deposited in layers.
  22. Define lateral morraine.
    A deposition of glacial sediment that forms along the side of a glacier.
  23. Define terminal morraine.
    Eroded debris that is dropped at the glacier's furthest extent.
  24. What can cause small glaciers to combine into a large glaicer?
    Small glacial tributaries.
  25. What is an erratic rock?
    Rocks deposited erratically by a passing glacier.
  26. How far did glaciers get in North America?
    As far as the Sierra Nevada mountains.