Social

• Early modern hostory

  • Geographical discoveries
  • Renaissance,Reformation and counterreformatiom
  • The two world wars
• Folding


  Bending of rock layers due to earth movements from one or two sides

  
• Faulting


  Movements in the crust of the earth that make cracks called faults
• Features formed by faulting

  • Rift valleys
  • Block/Horst mountains

  
• Volcanism


  The process by which molten rock (magma) is forced out to the surface of the earth
• Types of volcanoes


  • Active
  • Dormant
  • Extinct
• Volcanic eruption


  Has both negative and positive impacts on human life
• Earthquake


  Sudden movements in the earth's crust caused by internal movements deep down inside the earth
• Focus


  The point at which an earthquake originates
• Epicenter


  The point on the earth's surface immediately above the focus
• Richter scale


  The scale which gives the magnitude of an earthquake
• The Ring of Fire is a path along the Pacific Ocean characterized by active volcanoes and frequent earthquakes
• The majority of Earth's volcanoes (75%) and earthquakes (90%) take place along the Ring of Fire
• Effects of Earthquakes


  • Loss of life and destruction of property
  • Displacement of parts of the earth's crust vertically or laterally
  • Landslides and deep cracks in surface rocks
  • The devastation of cities, fires and diseases
  • The rise or lowering of the sea floor
• External forces


  Forces that act upon the earth's surface from the outside and level the ups and downs of the earth's surface
• Denudation


  The lowering of the land by wearing away of the surface of the earth, consisting of weathering and erosion
• Weathering


  The breaking down of rocks into smaller particles
• Types of weathering


  • Physical (mechanical)
  • Chemical
• External forces


  Forces that act upon the earth's surface from the outside
• Denudation


  The lowering of the land by wearing away of the surface of the earth
• Types of weathering


  • Physical (mechanical) weathering
  • Chemical weathering
• Physical weathering


  • Its main agents (causes) are temperature change, frost action and plant and animal action
• Physical weathering processes


  • Exfoliation (Onion skin weathering)
  • Frost action
• Chemical weathering


  A process which causes complete change in the internal structure of rocks
• Erosion


  The movement of broken rock and soil particles from one place to another by running water, wind, moving ice or sea waves
• Types of running water erosion

  • Sheet erosion
  • Rill erosion
  • Gully erosion
• Wind erosion


  • Wind is the strongest force of erosion in deserts
  • It picks up and transports grains of sand from one part to another part of the desert
• Landforms formed by wind erosion and deposition


  • Sand dune
  • Barchan
  • Loess deposit
• The air that surrounds the earth is called the atmosphere

  
• Aerosol


  Suspended dust particles and condensed moisture droplets which are collectively known as aerosols
• Major gases of the earth's atmosphere

  • Nitrogen
  • Oxygen
• Trace gases

  The remaining gases in the atmosphere other than nitrogen and oxygen
• Layers of the earth's atmosphere

  • Troposphere
  • Stratosphere
  • Mesosphere
  • Thermosphere

  
• Troposphere


  • It extends from sea level to 8/16 km
  • It contains three-fourth of the atmospheric mass
  • All kinds of weather changes take place only in this layer

  
• Stratosphere


  • It extends from the tropopause up to about 50 km
  • It has high concentration of ozone gases

  
• Mesosphere


  • It extends up from the stratopause to about 80/85 km
  • It is the coldest part of the atmosphere
  • It is the layer of strongest winds whose velocity is nearly 300 km/hour

  
• Thermosphere


  • It is the upper most layer of the atmosphere
  • It is characterized by a direct relationship between temperature and altitude
  • Temperatures get up to 725°C - 1,225°C

  
• Ionosphere


  • It extends from roughly 80 km to somewhere around 500 to 700 km above the earth's surface
  • It is a layer of electrically charged particles
• Exosphere


  • It is the outermost fringe of the atmosphere
  • It lies beyond about 500-700 km and is characterized by increasing hydrogen and helium content
• Weather


  The condition of the atmosphere over a short period of time