Layers of the Earth
Inner core, outer core, mantle, and crust.
What are the layers of the Earth in order from the center to the surface?
What causes earthquakes?
Sudden release of energy from shifting tectonic plates.
Continental drift
What is the theory that explains how continents move over time?
What does the Richter scale measure?
Magnitude of an earthquake.
Shaking and vibrations.
Buildings in earthquake-prone areas need special designs to withstand this.
The oceanic crust is denser and thinner, while the continental crust is thicker and less dense
What are the two types of Earth's crust, and how do they differ.
What is a seismic wave?
Vibrations that travel through Earth after an earthquake
1. Fossil evidence (same fossils found in continents that are separated by the ocean)
2. Matching coastlines (continents seem to fit together like a jigsaw puzzle)
3. Similar rock formations in continents that are separated by the ocean
What are three pieces of evidence that support the theory of continental drift?
What instrument records seismic waves?
Seismograph.
To prevent them from collapsing or shifting during an earthquake.
Why should buildings be firmly attached to the ground in earthquake-prone areas?
Pangaea was a supercontinent that later split into Gondwana and Laurasia
What was the name of the supercontinent that broke into Gondwana and Laurasia?
Name the three types of seismic waves.
Primary (P), Secondary (S), and Surface waves.
Seven major ones which move at a rate of a few centimeters per year.
How many major tectonic plates are there, and how fast do they move?
A seismograph records the
motion of the ground due to the earthquake and the time it occured.
Base isolators.
What feature, often placed at a building’s base, helps absorb earthquake shocks.
Convection currents in the mantle cause hot rock to rise, cool, and sink
What causes the movement of tectonic plates?
Describe the motion of surface waves.
They move rock particles in a backward, rolling motion and a side-to-side, swaying motion.
What are the three types of plate boundaries and how do they move?
Define magnitude
Magnitude is a measure of the energy that is released during an earthquake.
To absorb energy and prevent the building from breaking.
Why do engineers use flexible materials in earthquake-resistant buildings?
Because two continental plates are colliding (Indian plate is colliding with the Eurasian plate).
Why is the Himalayan mountain range still rising today?
Define the terms focus and epicenter of an earthquake.
Focus - underground origin; Epicenter - point on surface above focus.
Forms when a denser oceanic plate sinks beneath a continental plate, often causing earthquakes and volcanoes.
What is a subduction zone, and what happens there?
Draw a seismograph showing P, S, and surface waves.
Students draw
A large counterweight that moves opposite to shaking to reduce vibrations.
What is a tuned mass damper, and how does it help in earthquakes?