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What is the maximum displacement of a point of a wave from its rest position called?
What is the maximum displacement of a point of a wave from its rest position called?
S-waves can travel through both liquid and solid mediums.
S-waves can travel through both liquid and solid mediums.
False
Who first identified the separate arrivals of P-waves and S-waves on seismograms?
Who first identified the separate arrivals of P-waves and S-waves on seismograms?
Richard Oldham
The type of seismic wave that pushes and pulls rock in the same direction it travels is called a __________ wave.
The type of seismic wave that pushes and pulls rock in the same direction it travels is called a __________ wave.
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Match the following wave types with their characteristics:
Match the following wave types with their characteristics:
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Which type of wave is defined as moving particles in a medium perpendicular to its wave motion?
Which type of wave is defined as moving particles in a medium perpendicular to its wave motion?
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The wavelength of a wave is measured in seconds.
The wavelength of a wave is measured in seconds.
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What is the term for waves of energy caused by the sudden breaking of rock within the earth?
What is the term for waves of energy caused by the sudden breaking of rock within the earth?
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Which type of wave travels the fastest?
Which type of wave travels the fastest?
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The crust is the thickest layer of the Earth.
The crust is the thickest layer of the Earth.
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Who mathematically predicted the existence of Love waves?
Who mathematically predicted the existence of Love waves?
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The lithosphere comprises part of the crust and the upper part of the ______.
The lithosphere comprises part of the crust and the upper part of the ______.
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Match the following Earth layers with their characteristics:
Match the following Earth layers with their characteristics:
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Which of the following statements about the asthenosphere is correct?
Which of the following statements about the asthenosphere is correct?
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Rayleigh waves move the ground in a circular motion.
Rayleigh waves move the ground in a circular motion.
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What is the approximate temperature at the top of the mantle?
What is the approximate temperature at the top of the mantle?
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What is the primary composition of the inner core?
What is the primary composition of the inner core?
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The outer core is solid metal.
The outer core is solid metal.
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What does the term PANGAEA refer to?
What does the term PANGAEA refer to?
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The __________ discontinuity is the transition zone between the outer core and inner core.
The __________ discontinuity is the transition zone between the outer core and inner core.
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Match the following geological periods with their respective million years ago:
Match the following geological periods with their respective million years ago:
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Which evidence supports the Continental Drift Theory?
Which evidence supports the Continental Drift Theory?
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Alfred Lothar Wegener was a proponent of the Plate Tectonics Theory.
Alfred Lothar Wegener was a proponent of the Plate Tectonics Theory.
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Name one of the fossils that provide evidence for Continental Drift.
Name one of the fossils that provide evidence for Continental Drift.
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What is the main concept of Seafloor Spreading Theory?
What is the main concept of Seafloor Spreading Theory?
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Seafloor spreading and subduction contribute to maintaining the shape of the Earth.
Seafloor spreading and subduction contribute to maintaining the shape of the Earth.
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Who proposed the Seafloor Spreading Theory?
Who proposed the Seafloor Spreading Theory?
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New ocean crust is created at the ______.
New ocean crust is created at the ______.
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Match the following aspects of Seafloor Spreading Theory to their descriptions:
Match the following aspects of Seafloor Spreading Theory to their descriptions:
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What happens to the age, density, and thickness of oceanic crust as one moves away from the mid-ocean ridge?
What happens to the age, density, and thickness of oceanic crust as one moves away from the mid-ocean ridge?
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Continental Drift Theory and Seafloor Spreading Theory agree on the movement of continents.
Continental Drift Theory and Seafloor Spreading Theory agree on the movement of continents.
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What is the process called when old ocean crust is subducted and melts as it reaches the mantle?
What is the process called when old ocean crust is subducted and melts as it reaches the mantle?
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What happens when subduction is faster than seafloor spreading?
What happens when subduction is faster than seafloor spreading?
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Magnetic reversals occur at regular intervals of 100,000 years.
Magnetic reversals occur at regular intervals of 100,000 years.
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Define what a magnetic reversal is.
Define what a magnetic reversal is.
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The formula for the rate of seafloor spreading is RATE = __________ / TIME.
The formula for the rate of seafloor spreading is RATE = __________ / TIME.
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Match the following phenomena with their descriptions:
Match the following phenomena with their descriptions:
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What role do crystalized irons in rocks play in understanding the Earth's magnetic field?
What role do crystalized irons in rocks play in understanding the Earth's magnetic field?
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The Atlantic Ocean is expected to become larger than the Pacific Ocean due to plate divergence.
The Atlantic Ocean is expected to become larger than the Pacific Ocean due to plate divergence.
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Explain what mantle convection currents are.
Explain what mantle convection currents are.
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Study Notes
Seismic Waves
- Equilibrium: Undisturbed position of particles or fields, not vibrating.
- Crest: Highest point above the rest position in a wave.
- Trough: Lowest point below the rest position in a wave.
- Amplitude (A): Maximum displacement of a wave point from its rest position.
- Wavelength: Distance covered by a full wave cycle, measured in meters.
- Period (P): Time taken for a full wave cycle, measured in seconds.
- Frequency (f): Number of waves passing a point each second, measured in Hertz (Hz).
Types of Wave Motion
- Longitudinal Waves: Particles move parallel to wave direction; includes P-waves (Primary).
- Transverse Waves: Particles move perpendicular to wave direction; includes S-waves (Secondary).
Seismic Wave Types
- P-waves (Primary waves): Fastest seismic waves; travel through solid, liquid, and gas; compressional motion.
- S-waves (Secondary waves): Move rock up and down; slower than P-waves; can only travel through solids.
- Love Waves: Fastest surface waves; move ground side-to-side.
- Rayleigh Waves: Cause ground to shake in an elliptical motion; slowest surface waves.
Earth Layers
- Crust: Outermost solid layer, 5-35 km thick on land, 1-8 km under oceans; consists of tectonic plates.
- Lithosphere: Upper part of the mantle plus the crust, hard and brittle rock layer.
- Asthenosphere: Underlies the lithosphere; molten rock that flows like hot asphalt, facilitating plate movement.
- Mantle: Largest Earth layer, 2900 km thick; relatively flexible, flows, and has temperatures between 1600°F and 4000°F.
- Core: Divided into outer (liquid) and inner (solid); outer core is 2,250 km thick; inner core responsible for Earth's magnetic field, solid due to extreme heat and pressure.
Continental Drift Theory
- Pangaea: Supercontinent that existed during the Permian Period, existing approximately 250 million years ago.
- Alfred Wegener: Proposed that continents were once a single landmass that drifted apart.
Evidence for Continental Drift
- Fossil Evidence: Similar fossils found across separated continents, indicating land connection in the past.
- Matching Continents: Jigsaw-like fit of eastern South America and western Africa.
Seafloor Spreading Theory
- Proposes that new ocean crust forms at mid-ocean ridges and is destroyed at deep-sea trenches.
- Hess's Contribution: Suggested that continental drift is driven by seafloor spreading.
Mechanisms Supporting Seafloor Spreading
- Hot, less dense material rises, creating new seafloor as magma flows out and solidifies.
- Old oceanic crust is pushed away from ridges and can undergo subduction, melting back into the mantle.
Magnetic Reversal
- Occurs when Earth's magnetic poles switch; each reversal lasts less than 200,000 years.
- Symmetrical patterns of magnetic stripes on either side of mid-ocean ridges provide evidence of seafloor spreading.
Rate of Seafloor Spreading
- Calculated using the formula: RATE = DISTANCE / TIME.
- Ocean size changes based on relative rates of seafloor spreading and subduction.
Mantle Convection Currents
- Involves heat transfer in the lower mantle; magma rises as it heats and sinks as it cools.
- Heat generated from the decay of radioactive elements drives convection currents, enabling plate tectonics.
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Description
Explore the essential concepts of seismic waves in Unit 2. This quiz covers key terms such as equilibrium, amplitude, wavelength, and period, providing a solid understanding of wave behavior in physical science. Test your knowledge and comprehension of these fundamental principles.
