Landforms caused by deposition

• What are the reasons for changing glacial coverage?


  Broader environmental system changes, eccentricity, axial tilt, wobbling, solar outputs, sunspots, and volcanic activity
• How does eccentricity affect glacial coverage?

  Eccentricity changes the Earth's orbit from circular to elliptical, causing less solar coverage
• What is the effect of axial tilt on glacial coverage?

  Axial tilt causes the Earth's tilt to vary between 21.8 and 24.4 degrees
• What role does volcanic activity play in changing glacial coverage?

  Volcanic activity can block out sunlight and reflect it, affecting glacial coverage
• What is a till sheet?

  A till sheet is an area of flat relief with unstratified drift deposited at the end of glacial advances
• How does a till sheet affect the underlying rock surface?

  A till sheet smooths the underlying rock or surface
• What is an erratic?


  An erratic is an individual piece of rock transported away from its source by a glacier
• How is an erratic formed?

  An erratic is formed from rocks of different geology than the area where they are deposited, eroded by plucking and weathering
• What is the process of drumlin formation?

  In a U-shaped valley, unsorted glacial till flows past an obstruction, molding the till into an oval-shaped hill after the glacial period
• What is a drumlin?

  A drumlin is a mound of glacial debris streamlined into an elongated hill with a blunt stoss side and smooth lee side
• What is a ground moraine?


  A ground moraine is an irregular blanket of till deposited under a glacier
• What is a recessional moraine?


  A recessional moraine is a series of ridges running transversely across glacial troughs, formed when a retreating glacier stays stationary
• What are the characteristics of a terminal moraine?

  Terminal moraines are crescent-shaped, mark the maximum advance of the glacier, and consist of debris scooped and deposited by the glacier's snout
• What are the characteristics of a recessional moraine?

  Recessional moraines are found further up the valley and formed during temporary standstill of retreating glaciers
• What is a lateral moraine?

  A lateral moraine is material deposited on the sides of a glacier
• How is a lateral moraine formed?

  A lateral moraine forms from materials accumulating from the valley sides, weathering, and deposition as the glacier retreats
• What are the three types of moraines?

  • Terminal moraine
  • Recessional moraine
  • Lateral moraine