PT

• What is a fault in geology?

  A crack or fracture in the Earth's crust
• What happens during the stick and slip process?

  Energy is released after overcoming friction
• Why might rocks not generate earthquakes when moving along faults?

  If rocks are ductile, they may bend without breaking
• What is the stick and shake process in relation to earthquakes?

  Energy makes rocks bend until they snap
• What is an earthquake?


  The vibration of the Earth due to energy release
• What are the parts of a fault?

  • Fault line: fracture line on the surface
  • Fault plane: plane of rupture
  • Fault sharp: cliff of exposed fault plane
  • Footwall: block below the fault plane
  • Hanging wall: block above the fault plane
  • Focus: origin of the earthquake
  • Epicenter: point above the focus on the surface
• What is the fault line?

  The fracture line on the Earth's surface
• What is the fault plane?

  The plane along which rupture occurs
• What is the footwall in a fault?

  The block below the fault plane
• What is the hanging wall in a fault?

  The block above the fault plane
• What is the focus of an earthquake?

  The origin of the earthquake
• What is the epicenter of an earthquake?

  The point on the surface above the focus
• What are the types of faults and their characteristics?

  • Normal Fault: hanging wall moves down (tensional stress)
  • Reverse Fault: hanging wall moves up (compressive stress)
  • Thrust Fault: reverse fault with a dip ≤ 45 degrees
  • Strike-slip Fault: horizontal movement with minimal vertical displacement
• What characterizes a normal fault?

  The hanging wall moves downward relative to the footwall
• What is a thrust fault?

  A reverse fault with a dip of 45 degrees or less
• What characterizes a reverse fault?

  The hanging wall moves upward relative to the footwall
• What characterizes a strike-slip fault?

  Movement is primarily horizontal with minimal vertical displacement
• Richter Scale - logarithmic scale that calculates earthquake size by measuring ground motions on a seismograph
• Richter Scale - is developed by Charles F Richter in 1935
• moment magnitude scale is based on the seismic moment of an earthquake
• When was moment magnitude scale develop?

  1970’s
• Who developed the moment magnitude scale?

  Hiroo Kanamori and Thomas C. Hanks
• Moment Magnitude Scale - it is the standard scale used by seismological authorities
• Richter Scale - is a local magnitude scale
• Richter Scale - it is best for small to moderate earthquakes ( magnitude measuring )
• Moment Magnitude Scale - best or accurate for measuring earthquakes of all sizes. It is also known as the global magnitude scale.
• SEISMIC WAVES are vibrations generated by an earthquake, and these are also mechanical waves
• if a seismic wave speeds up, what do you think is happening or where are they traveling?

  They are traveling in a layer that is more dense and more rigid
• What do you think is happening to a seismic wave if it’s slows down? where are they travelling

  On a layer that is less dense and less rigid
• Inner Rainbands - rainbands that are called the maximum sustained winds
• Rainbands - it is the secondary cell that spirals into the center of the storm. It is a part of a Typhoon.
• In the northern hemisphere air rotates in a counterclockwise manner towards the center of the typhoon
• In the southern hemisphere air spirals clockwise towards the
• Conditions for a typhoon to form

  • pre existing disturbance

  • Low atmospheric stability

  • warm ocean water

  • sufficient coriolis force

  • the presence of ITCZ

  •high humidity

  •Low vertical wind shear
• In typhoons, cold air moves down, warm air rises
• typhoons gain power as they move over warm bodies of water
• typhoons are most likely to do the most damage near the seaboard
• Northwestern Pacific Ocean is the most active basin for the formation of cyclones
• 20 typhoon are estimated number of storms that enter the Philippine area responsibility every year
• low vertical wind shear and ocean water with 15°C, can weaken a typhoon