• Unit Three-The Dynamic Crust

    What You'll Learn 1:

    • Why continental drift was not accepted when it was first proposed and what kinds of evidence lead to its acceptance.
    • How Earth's tectonic plates interact.
    • What causes tectonic plates to move.

    Why It's Important 1:

    Understanding the theory of plate tectonics is important because interactions between the enormous slabs of Earth's crust and rigid upper mantle results in the formation of many of Earth's surface features, including volcanoes and some mountain ranges.  Many earthquakes are also caused by plate movements.

    Key Vocabulary 1:

    continental driftPangaea
    magnetic reversal
    seafloor spreading
    convergent boundary
    divergent boundary
    rift valley
    theory of plate tectonics
    transform boundary
    ridge push
    slab pull

    Key Concepts/Understandings 1:

    • Describe one piece of early evidence that led people to suggest that Earth's continents may have once been joined.
    • Discuss evidence of continental drift.
    • Explain why continental drift was not accepted when first proposed.
    • Summarize the evidence that led to the discovery of seafloor spreading.
    • Explain the significance of magnetic patterns on the seafloor.
    • Explain the process of seafloor spreading.
    • Explain the theory of plate tectonics.
    • Compare and contrast the three types of plate boundaries and the features associated with each.
    • Explain the process of convection
    • Summarize how convection in the mantle is related to the movements of tectonic plates.
    • Compare and contrast the processes of ridge push and slab pull.
    What You'll Learn 2:
    • How magma forms.
    • What kind of features form as a result of igneous activity within Earth.
    • How volcanoes form and how they can be classified.
    Why It's Important 2:

    Many of Earth's internal processes help to shape out planet's surface.  Volcanic activity within Earth and at its surface produce many of the mountains and rock formations on Earth.

    Key Vocabulary 2:

    cinder-cone volcano
    composite volcano
    hot spot
    shield volcano

    Key Concepts/Understandings 2:
    • Describe factors that affect the formation of magma.
    • Compare and contrast the different types of magma.
    • Expain how magma affects overlying crustal rocks.
    • Compare and contrast intrusive igneous rock bodies.
    • Describe the major parts of a volcano.
    • Compare and contrast shield, cinder-cone, and composite volcanoes.
    • Contrast the volcanism that occurs at plate boundaryies.
    • Explain the relationship between volcanism and hot spots.
    What You'll Learn 3:
    • What cause earthquakes and how they affect Earth's surface.
    • How earthquakes and the destruction they cause are measured.
    • What factors determine siesmic risk.
    Why It's Important 3:

    Earthquakes are natural phenomena that can cause vast amounts of damage as well as many deaths.  Understanding what csues earthquaked is essential to our being prepared from these natural disasters.

    Key Vocabulary 3:

    primary wave
    secondary wave
    surface wave
    modified Mercalli scale
    moment magnitude scale
    Richter scale
    seismic gap

    Key Concepts/Understandings 3:
    • Define stress and strain as they apply to rocks.
    • Distinguish among the three types of faults.
    • Contrast three types of seismic waves.
    • Describe how a siesmometer works.
    • Expalin how siesmic waves have been used to determine the structure and composition of Earth's interior.
    • Compare and contrast earthquake magnitude and intesity and the scales used to measure.
    • Expalin why data from at least three seismic stations are needed to locate an earthquake's epicenter.
    • Describe siesmic belts.
    • Discuss factors that affect the amount of damage done by an earthquake.
    • Explain some of the factors considered in earthquake probability studies.
    • Define seismic gaps.
    What You'll Learn 4:
    • Why Earth's displaces the mantle on which it rests.
    • How different processes create mountias that rise above Earth's surface.
    Why It's Important 4:

    All mountains rise above the surrounding land, yet each of these awesome structures is unique.  Understanding the various processes involve in mountain building is critial to our understanding of the dynamic planet on which we live.

    Key Vocabulary 4:
    isostatic rebound
    fault-block mountain
    pillow baslat
    uplifted mountains

    Key Concepts/Understandings 4:
    • Describe the elevation distribution of Earth's surface.
    • Explain isostasy and how it pertains to Earth's montains.
    • Describe how Earth;s crust responds to the addition and removal of mass.
    • Compare and contrast the different typyes of mountains that form along convergent plate boundaries.
    • Explain how the Appalachian Montains formed.
    • Describe the montain ranges that form along ocean ridges.
    • Compare and contrast uplifted and fault-block mountains.
    • Describe the mountains that form as a result of hot spots in Earth's mantle.


Last Modified on February 23, 2015