Along the Plate Edge (Quiz 2.1)

• Michoacan, Mexico

  • Eruption of Mt. Paricutin (1943-1952)
  • Located in Trans-Mexican Volcanic Belt
• Tohoku, Japan

  • A 9.0 - magnitude earthquake on March 11, 2011
  • Originated below the sea near subduction zone that causes tsunami
• Christchurch, New Zealand

  • A 6.3 - magnitude earthquake on February 22, 2011
  • Caused by the movement of 15-km shallow fault
• Chile

  • 8.2 earthquake
  • Feb. 27, 2010 and April 1, 2014
• Luzon, Philippines

  • Mt. Pinatubo eruption last 1991 after more than 500 years.
  • It released tons of SO2 into the atmosphere.
• Ring of Fire

  • These countries lie near a zone in Pacific Ocean characterized with active volcanoes and frequent earthquakes.
• Plate movements

  • Convergent
  • Divergent
  • Transform fault
• Divergent Boundary

  • 2 plates are moving away from one another, creating a gap between them which widens to become rift valleys
• Divergence Impacts

  • 2 continental plates produce rift valleys
  • 2 oceanic plates produce mid-ocean ridges
• Divergent Boundary

  • Volcanic islands are formed when lava fills the gap and later on becomes part of ocean floor.
• Example of a divergent boundary

  • Great East African Rift Valley
• Convergent Boundary

  • 2 plates are moving toward one another, forming a subduction zone and orogenic belt.
• Oceanic-Oceanic

  • Subduction happens, descending plate melts and rise to form volcanoes
  • Ex: Pacific-Philippine Plate
• Oceanic-Continental

  • Oceanic Plate subducts, melts and rise to volcanoes. Continental Plate deforms. Trenches are also formed
• Continental-Continental

  • Sutured, creating mountain ranges. Examples are Alps and Himalayas.
• Transform Fault

  •  2 plates sliding against each other

  In opposite direction

  • No landforms produced --> Earthquakes produced
• Earthquake

  • shaking of the earth resulting in the breaking and shifting of rocks
  • Releases seismic energy
  • Creates cracks called faults
• Types of faults

  • Reverse
  • Normal
  • Strike-slip
  • Oblique
• Reverse Fault

  • The original wall goes up, and the other hangs
• Normal Faults

  • The original wall is hanging
• Strike-slip fault

  • Two plates slide horizontally past each other
• Oblique Fault

  • combination of normal/reverse fault and strike slip fault
  • most destructive
• Hypocenter

  • aka focus, source of seismic waves
• Epicenter

  •  directly above the focus
• Depth of focus:

  • Shallow - 10-100 km
  • Intermediate - 70-300 km
  • Deep - 300 km deeper
• How do scientists locate earthquakes?

  Triangulation Method
• Triangulation Method

  •  the intersection of 3 circles is the epicenter
• Orogenesis

  • process of forming mountains through collision and compression
• Fold Mountains

  • formed through plate convergence with forces of compression
  • Ex. Himalayas
• Volcanic mountains

  • produced by hotspots, constructed from accumulated lava flow
• Erosion-formed mountains

  • formed by rock erosion and weathering
• Erosion

  • transfer of weathered rocks from one place to another
• Weathering

  • breaking down or dissolving of rocks
• Dome mountain range

  • upwarping of tectonic plates
  • Not accompanied by collision of plate boundaries
• Fault-block Mountain

  • displacement of crust produces numerous cracks  while slides down.
• WVF - West Valley Fault
• PHIVOLCS - Philippine Institute of Volcanology and Seismology
• West Valley Fault - home of the fault we have in manila
• K2 - second highest mountain
• Mt. Everest - highest mountain