Chapter 2

• Landform


  A feature on the Earth's surface that is part of the terrain
• Major landforms


  • Mountains
  • Hills
  • Plateaus
  • Plains
• Minor landforms


  • Buttes
  • Canyons
  • Valleys
  • Basins
• Landform creation


  1. Tectonic plate movement pushing up mountains and hills

  2. Erosion by water and wind wearing down land and creating landforms like valleys and canyons
• The highest landform on Earth is Mount Everest in Nepal, measuring 8,850 meters (29,035 feet) above sea level
• Landforms can exist under water in the form of mountain ranges and basins under the sea
• Categories of landforms


  • Landforms that are built (depositional)
  • Landforms that are carved (erosional)
  • Landforms that are made by movements of the Earth's crust (tectonic)
• Erosion


  A process of geological denudation, which involves the breakdown and transport of rock materials
• Weathering


  The fragmenting of rock by physical, chemical and biological means
• Mass wasting


  Gravity pulling the rubble of weathering from its source
• Deposition


  The process where an agent of erosion drops part or its entire load of rocks and sediments
• Nearly 27% of the world's land surface is covered by mountains
• Up to 80% of the planet's fresh surface water comes from mountains
• About 12% of the world's population lives in the mountains, but over 50% are directly or indirectly dependent on mountain resources
• Classification of mountains


  • Fold mountains
  • Block mountains
  • Volcanic/Accumulated mountains
  • Residual/Relict mountains
• Fold mountains


  Mountain ranges mainly consisting of uplifted folded sedimentary rocks, formed due to the force of compression from endogenic forces
• Block mountains


  Formed by the internal or endogenic earth movements which cause the force of tension and faulting
• Volcanic/Accumulated mountains


  Mountains formed by the accumulation of volcanic materials
• Residual/Relict mountains


  Portions of an elevated area that escape weathering due to the hardness of the materials, while the surrounding area gets eroded
• Economic significance of mountains


  • Storehouse of natural resources
  • Generation of hydroelectricity
  • Abundant source of water
  • Formation of fertile plains
  • Natural political frontiers
  • Effects on climate
  • Tourist centers
• Plateau


  An elevated area with a more or less levelled land on its top, with a large area on its top and a steep slope on its sides
• Classification of plateaus


  • Intermontane plateaus
  • Piedmont plateaus
  • Continental plateaus
  • Volcanic plateaus
  • Dissected plateaus
• Intermontane plateaus


  Plateaus bordering or enclosed within mountain ranges
• Piedmont plateaus


  Plateaus situated at the foot of a mountain and locked on the other side by a plain or a sea/ocean
• Continental plateaus


  Formed either by an extensive continental upliftment or by the spread of horizontal basic lava sheets
• Volcanic plateaus


  Plateaus produced by volcanic activity, either by fluid basaltic lava or massive pyroclastic flows
• Dissected plateaus


  Plateau areas that have been severely eroded, appearing mountainous
• Economic significance of plateaus


  • Storehouse of minerals
  • Generation of hydropower
  • Cool climate
  • Animal rearing and agriculture
• Plain


  A low-lying relatively flat land surface with very gentle slope and minimum local relief
• Classification of plains


  • Structural plains
  • Erosional plains (Peneplains)
  • Depositional plains
• Structural plains


  Formed by the upliftment or subsidence of a part of the sea floor or continental shelf
• Erosional plains (Peneplains)


  Formed by the continuous and longtime erosion of uplands
• Depositional plains


  Formed by the depositional activity of various geomorphic agents like rivers, lakes, glaciers, and wind
• Types of depositional plains

  • Riverine/Alluvial plains
  • Lacustrine/Lake plains
  • Glacial/Drift plains
  • Loess plains
• Economic significance of plains


  • Not provided
• e plains


  Mainly formed by the upliftment of a part of the sea floor or continental shelf
• e plains are located on the borders of almost all the major continents
• Structural plains


  May also be formed by the subsidence of areas
• Peneplains


  Almost plain surface
• Depositional Plains


  Formed by the depositional activity of various geomorphic agents