2nd Quarter

• volcanoes mountain that opens downward to a reservoir of molten rock
• temperature is directly proportional to pressure
• Hotspot is the area where there is active volcanism
• Volcanism releases magma through earth surface
• Near tectonic plates are where volcanoes can be found
• volcanoes are formed through the collision of plate boundaries
• Volcano life cycle

  • magma invasion
  • building pressure
  • eruption
• John Tuzo Wilson he discovered 3 linear chains of volcanoes and submarine volcanoes that are thousand miles apart
• Hawai Emperor Seamount most well known of the three and the youngest
• Volcanic chains are the result of the slow movement of a tectonic plate across a fixed hotspot
• William Jason Morgan proposed the existence of roughly cylindrical convective upwelling on Earth's manner
• Areas with Hotspots

  • Hawaii
  • Iceland
  • Reunion
  • Galapagos
  • Yellowstone
• Mantle plumes

  • columns where heat or rocks in the mantle rises
  • connector
• Hotspot caused by the convection of hot mantle at the mantle plume
• Convection occurs when matter such as magma circulates within Earth
• Magma is heated -> expands, less dense
• Active volcano signs

  • crater widens > magma chamber is active
  • frequent earthquakes
• 450 volcanoes can be found in the Pacific Ring of fire
• Earthquake abrupt and violent shifting of tectonic plates
• Earthquake types of wave energy that ravel through bedrock
• Hypocenter / Focus origin of earthquake
• Epicenter point on the earth's surface directly above the focus
• seismic waves

  1. surface
  2. body
• Surface waves only travels on the surface

  1. love - parallel , most damaging
  2. Rayleigh (ground roll) - elliptical
• body waves interior of the earth, faster than surface

  1. P waves - travels through all types of matter , faster than S wave
  2. S wave - travels only through solid
• Interior of the earth mostly made up of liquid and has high temperature
• High temperature one of the causes fir speed
• Seismology study of earthquakes
• Robert Mallet postulated that earthquakes consisted mainly of longitude motion
• Pendulum generates the movement of the frame which generates record of the vibration
• Richter determines magnitude, 8 units
• Mercalli intensity of the earthquake, 12 units
• Guiseppe Mercalli invented Mercalli in 1902
• Charles F. Richter developed Richter in 1934
• Thomas C. Hanks and Hiroo Kanamori developed Moment Magnitude Scale (MMS) in 1979
• Types of Earthquake

  1. Tectonic - common
  2. volcanic - warning for volcanic eruptions
  3. collapse - caused by mining
  4. explosion - caused by Chemical uses
• Foreshocks small earthquakes that commonly precede a major one
• Aftershocks small earthquakes after the major one
• Seiche large water wave that moves up and down instead of forward \
• fault crack across the rocks that have been offset