Tectonic Activity Map of the Earth

Unit 6: Plate Tectonics

  •  

    Things for Unit 6 you should UNDERSTAND, KNOW, and be able to DO...
     
    Understand:
    • The Theory of Plate Tectonics is supported by a growing body of evidence.
    • The geography, climate and organic evolution of Earth has gone through- and continues to go through - a constant state of change.
    • How has the collection of ongoing evidence changed our views of crustal activity?
    Know:
    • Properties of Earth’s internal structure (crust, mantle, inner core, and outer sore) can be inferred from the analysis of the behavior of seismic waves (including velocity and refraction) 
      • The more dense and rigid a material is, the greater the velocity of the seismic waves.
      • P-waves will pass through solids, liquids and gases.  
      • S-waves will only pass through solids.  S-waves do not pass through the outer core of the Earth; therefore, the outer core is liquid.
    • Evidence leads to the inference that Earth’s interior is composed of layers that differ in composition and states of matter.
    • Analysis of seismic waves allows the determination of the location of earthquake epicenters, and the measurement of earthquake magnitude.
      • P-waves travel faster than all other types of seismic waves.  S-waves are the second fastest.
      • The farther an observer is from an epicenter, the larger the time interval between the P-waves and S-waves.
      • To find the position of the epicenter, at least three seismograph locations must be used.
    • The lithosphere consists of separate plates that ride on the more fluid asthenosphere. These plates move slowly in relationship to each other, indicating Earth is a dynamic geologic system.
    • Earth’s systems have internal sources of energy which creates heat and regions of density differences. These differences result in motion.
    • There are three types of plate boundaries (divergent, transform, convergent) each resulting in different geologic activity and landforms.
    • Regions located close to plate boundaries are more likely to experience tectonic activity
    • The continental crust is thicker, less dense compared to the oceanic crust which is thinner, denser.
    • New ocean crust continues to form at mid-ocean ridges.
    • Earthquakes and volcanoes present geologic hazards to humans which can be reduced through emergency preparedness.
    • Many of the Earth’s surface features (mid-ocean ridges, trenches, mountain ranges, subduction zones, hot spots, magnetic and age patterns are consequences of forces associated with plate motion and interactions.
      • Many processes of the rock cycle are consequences of plate dynamics.
        • The production of magma occurs at both subduction and rifting regions.
        • Regional metamorphism occurs within subduction zones.
        • The creation of major depositional basins occurs through down-warping of the crust.
     
    • Landforms are the result of the interaction of tectonic forces and the processes of weathering, erosion, and deposition.
     
    Vocab Terms: Asthenosphere, continental drift, convection, convergent boundary, crust, p-wave, s-wave, divergent boundary, earthquake, epicenter, fault, focus, hotspot, lithosphere, magnitude, mantle, mid-ocean ridge, origin time, Pangea, plate boundary, plate tectonics, Richter scale, sea-floor spreading, seismic station, seismograph, subduction zone, transform boundary, trench, shadow zone, refraction, geologic activity, landform, inner core, outer core, Ring of Fire
     
    Extended Vocabulary: tsunami, magnetic reversal, Moho, volcano, hydrothermal vents
     
    Do:
    • Compare and contrast the characteristics of P and S-waves.
    • Analyze P and S-wave arrival times from three seismic stations to locate the epicenter of an earthquake using ESRT page 11. 
    • Determine the distance from an epicenter by using P and S-wave arrival times and ESRT page 11.
    • Describe inferred properties of Earth’s interior using earthquake time/travel data (shadow zones).
    • Explain measurement of earthquake energy (Richter Scale and Mercalli Scale).
    • Describe the features and locations of plate boundaries.
    • Identify the direct and indirect evidence of crustal movement.
    • Describe the evidence of continental drift.
    • Explain how heat and density result in the movement of crustal plates.
    • Use page 5 of the ESRT to determine the relative motion at plate boundaries.
    • Use Inferred Properties of Earth’s Interior (page 10 ESRT) to determine how temperature, pressure, and density change with depth.

Related Files