Vocabulary
energy released by earthquakes under earth's surface
seismic waves
Name the three compositional layers of earth's interior
Crust, Mantle, Core
What is the theory of continental drift?
hypothesis that today’s continents were once part of a single landmass (called Pangaea)
Name the three types of stress that occurs at plate boundaries.
compression, tension, shear stress
What is an earthquake?
ground movements that occur when blocks of rock in Earth move suddenly and release energy
where the first motion of an earthquake occurs
focus
Name the three physical layers of earth's interior
Lithosphere, Asthenosphere, Mesosphere
What is the theory of plate tectonics?
states that Earth’s surface is made up of giant, moving slabs called tectonic plates
Name the three types of plate boundaries
Convergent, Divergent, and Transform
What are earthquakes like at divergent boundaries?
Normal faults and shallow earthquakes
process of hot materials rising and cold materials sinking due to density differences
convection current
What is the main difference between the inner core and outer core
Inner core is solid and outer core is liquid
What three things support the idea of continental drift?
1. Shapes of continents
2. Rocks and Fossils
3. Climatic Evidence
What three landforms are created at convergent boundaries?
1. Folded Mountains
2. Volcanoes
3. Ocean Trenches
What are earthquakes like at convergent boundaries?
plates collide and can create very strong earthquakes
process by which one plate gets pulled beneath another plate
subduction
What three things raised earth's temperature as it formed?
1. Collisions
2. Gravity
3. Radioactive Decay
What three things provide evidence of plate tectonics?
1. Sea-Floor Spreading
2. Properties of Sea floor
3. Locations of Volcanoes and Earthquakes
What landforms are created at divergent boundaries?
1. Fault-Block Mountains
2. Rifts and Ridges
What causes an earthquake?
As plates move, pressure builds up near the edges of the plates
These movements break earth’s crust into series of faults
after the sudden snap of the earthquake, the return of the rock to its original shape when stress is removed
elastic rebound
Explain the four steps that took place when earth first formed.
Large cloud of dust and gas called Solar Nebula collapses and begins to rotate
Over time solar nebula flattens into a swirling disk of matter with sun at the center
Particles in the disk collide due to force of gravity and stick together to form larger bodies
The largest bodies became planets, such as earth. The eight planets separated and began orbiting the sun
What three processes cause tectonic plates to move?
1. Mantle Convection
2. Ridge Push
3. Slab Pull
Why is plate tectonics so important to society?
Helps protect and prepare for natural disasters (earthquakes, volcanic eruptions, tsunamis)
Helps locate valuable minerals and resources near tectonic boundaries
Helps discover how earth’s surface has formed and helps predict for the future what may happen (What will happen to our planet?!)
What are some effects of earthquakes?
1. Danger to people and structures
2. Tsunamis