Geography: Landforms and Processes

Mountain Formation

• Process of Mountain Building:
  • Folding: compression of Earth's crust causing rocks to buckle and fold
  • Faulting: movement along faults creating mountains through uplift and erosion
  • Volcanic activity: accumulation of volcanic rocks and lava flows
• Types of Mountains:
  • Fold mountains (e.g., Himalayas)
  • Volcanic mountains (e.g., Mount St. Helens)
  • Block mountains (e.g., Sierra Nevada)

Plate Tectonics

• Theory: Earth's lithosphere is broken into large plates that move relative to each other
• Types of Plate Boundaries:
  • Divergent: plates moving apart (e.g., Mid-Atlantic Ridge)
  • Convergent: plates moving towards each other (e.g., Andean mountain building)
  • Transform: plates sliding past each other (e.g., San Andreas Fault)
• Plate Interactions:
  • Continental drift: movement of continents
  • Seafloor spreading: creation of new oceanic crust

Volcanic Landforms

• Volcanic Features:
  • Shield volcanoes: gently sloping, broad volcanoes (e.g., Hawaiian Islands)
  • Composite volcanoes: steep-sided, conical volcanoes (e.g., Mount Fuji)
  • Calderas: large depressions formed by volcanic collapse (e.g., Crater Lake)
• Volcanic Landforms:
  • Lava flows: solidified molten rock
  • Volcanic ash: fine particles ejected during eruptions

Desert Landforms

• Desert Features:
  • Dunes: wind-formed ridges of sand
  • Playas: dry lake beds
  • Mesa: flat-topped hills formed by erosion
• Desert Processes:
  • Deflation: removal of fine particles by wind
  • Erosion: wear and tear of desert surfaces
  • Deposition: accumulation of sediment in deserts

Coastal Features

• Coastal Processes:
  • Wave action: erosion and deposition by ocean waves
  • Tides: periodic rising and falling of sea level
  • Currents: movement of water along coastlines
• Coastal Landforms:
  • Beaches: gently sloping zones of sediment
  • Cliffs: steep slopes formed by erosion
  • Headlands: rocky formations jutting into the sea