• Save
Module 2 Week 3 Tectonic Features
Upcoming SlideShare
Loading in...5
×

Like this? Share it with your network

Share
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,883
On Slideshare
1,520
From Embeds
363
Number of Embeds
4

Actions

Shares
Downloads
0
Comments
0
Likes
1

Embeds 363

http://eperalta.org 159
http://online.peralta.edu 118
http://www.eperalta.org 85
http://www.otakicollege.knowledge.net.nz 1

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Tectonic Features Orogeny, Volcanism, and Earthquakes
  • 2. Overview
    • Orogeny
      • Plate Boundaries and Mountain Building
    • Volcanism
      • Types of Volcanoes
      • Properties of Volcanoes
      • Plate Boundary Associations
    • Earthquakes
      • Earthquakes and Faults
      • Earthquake Properties
      • Earthquake Damage
  • 3. Orogeny
    • Important orogenies
      • Allegheny Orogeny: Appalachian and Ozark Mountains; 250 – 300 million years ago
      • Sierra Nevadan Orogeny: produced the Sierra Nevada; 130 –160 million years ago
      • Alpine Orogeny: produced the Alps; 20 –120 million years ago
      • Laramide Orogeny: produced Rocky Mountains; 40 – 80 million years ago
      • Himalayan Orogeny: Produced the Himalayas; 45-50 million years ago
  • 4. Types of Orogenies
    • Associated with subduction zones
    • Oceanic plate-continental plate collisions
      • Andes, Sierra Madre, Rocky Mountains
      • Folded sedimentary strata, igneous intrusions, terranes, volcanism
    • Oceanic plate-oceanic plate collisions
      • Produce volcanic islands
      • Most of the islands arcing around the Pacific Rim; Indonesia, Aleutians, Japan
    • Continental plate-continental plate collisions
      • Himalayas, Alps
      • Intense folding, overthrusting, faulting and uplifting
  • 5.  
  • 6.  
  • 7.  
  • 8.  
  • 9.  
  • 10. Volcanoes
    • Volcanic landforms
      • Cinder cones, calderas, shield volcanoes, plateau basalts, composite volcanoes
      • Calderas form on any volcano when the original structure collapses
    • Locations of volcanic activity
      • Subduction boundaries (c-o, o-o)
      • Seafloor spreading and rifts
      • Hot spots
    • Types of eruptions
      • Effusive
      • Explosive
    • Eruption material
      • Lava
      • Pyroclastic material (tephra): ash, dust, cinders, scoria, pumice and aerial bombs
      • Gases
  • 11. Effusive Eruptions
    • Gentle eruptions producing mostly lava and gases
      • magma direct from the asthenosphere
      • low-viscosity and fast flowing
      • produces basalt
    • Landforms
      • Shield Volcanoes
        • gentle slopes, gradually rising to a summit crater
        • Often associated with hotspots
      • Plateau Basalts
        • Associated with rifts
        • Magma spreads out across surface
  • 12.  
  • 13.  
  • 14.  
  • 15.  
  • 16.  
  • 17.  
  • 18.  
  • 19. Explosive Eruptions
    • Violent, explosive eruptions
      • Associated with subduction zones
      • Thick, viscous magma rising from subducted plates clogs vents in the volcano, allowing gases to build up to an explosion
    • Landforms
      • Cinder cones
        • less explosive eruptions
        • pyroclastic material builds up into a conical shape
      • Composite volcanoes (stratovolcanoes)
        • More explosive
        • Eject alternating layers of lava and pyroclasts, creating composite strata
        • Steep sides, conical shape, often very symmetrical
        • Mt. St. Helens
  • 20.  
  • 21.  
  • 22.  
  • 23. Earthquakes
    • Caused by motion along faults
      • Elastic rebound theory
        • Friction holds fault blocks motionless until strain exceeds friction
        • Sudden motion, at a point ( asperity ), releasing energy
      • The point in the earth where the slippage occurs is called the focus
      • The point on the surface directly above the focus is called the epicenter .
    • The strength of an earthquake felt at any given point depends on
      • Depth to the focus
      • Distance to the epicenter
      • Amount of energy released
      • Geological material; bedrock is better than loose sediments because of liquefaction
  • 24.  
  • 25. Surface Fault Epicenter Focus
  • 26. Measuring Earthquakes
    • Mercali scale
      • 1902
      • Intensity
      • Qualitative
    • Richter scale
      • 1935
      • Wave Amplitude
      • Quantitative
        • Logarithmic: each number represents a ten fold increase in amplitude, and a 31.5 increase in energy.
    • Moment Magnitude scale
      • 1993
      • Fault slippage, surface disturbance, geologic material
      • Quantitative
  • 27.  
  • 28.  
  • 29. After-Affects of Earthquakes
    • Topographic changes in elevation
      • Valdiva, Chile, 1960: 400 km 2 area dropped 7–9 meters
    • Tsunamis
      • Tallest measured wave: 70 meters
      • December 26, 2004 – Indian Ocean
        • 9.0 Magnitude quake off of Sumatra moves the island 150 ft West
        • triggered a tsunami with a large inland surge
        • Quake and Tsunami combined killed over 250,000 people
    • Catastrophic rockslides
    • Landslides