Earth's Layers
This is the thinnest and least dense chemical layer of Earth.
What is the crust?
This is the definition of density.
How much stuff is crammed into a certain space?
This theory states that continents and oceans are found on large plates that are constantly moving.
What is the Theory of Plate Tectonics?
This is where the youngest rocks in the Atlantic Ocean are found.
What is a mid-ocean ridge?
This is the point on the Earth's surface directly above where an earthquake begins.
What is the epicenter?
This specific volcanic hazard is a fast-moving mudflow made of ash mixed with water.
What is a lahar?
These are the two metallic elements that make up both the inner and outer core composition.
What are iron and nickel?
This is the formula used to calculate density.
What is density = mass/volume?
This is the primary force in the mantle that causes tectonic plates to move.
What are convection currents?
The seafloor age pattern in this ocean is considered "more complicated" because the youngest crust is not in the center.
What is the Pacific Ocean?
This type of seismic wave is the fastest and can travel through both solids and liquids.
What are P-waves? (Primary Waves)
These can form when an underwater earthquake vertically shifts the seabed, displacing huge amounts of water.
What is a tsunami?
This rigid mechanical layer is composed of the crust and the uppermost part of the solid mantle.
What is the lithosphere?
This is the accepted density of pure water.
What is 1.0 g/mL?
This type of boundary occurs when two plates slide past each other horizontally, like the San Andreas Fault.
What is a transform boundary?
This is the pattern found in rock ages on the seafloor when you move away from a mid-ocean ridge.
What is rock age increases with distance from the mid-ocean ridge?
This type of seismic wave provides evidence that the outer core is liquid because it cannot travel through fluids.
What are s-waves (shear/secondary waves)?
This is a famous volcano in the United States that is not located at a plate boundary but over a "hot spot."
What is Yellowstone? Hawaii would also be an accepted answer.
This "soft", partially molten layer of the mantle that allows the tectonic plates to move.
What is the asthenosphere?
This material is denser than continental crust, which is why it sinks into the mantle during subduction.
What is oceanic crust (or basalt)?
This geologic feature forms when two continental plates collide, causing the crust to rise up.
What are mountains?
This type of boundary is found at mid-ocean ridges where two plates are separating.
What is a divergent boundary?
This modern scale has replaced the Richter Scale to measure the total energy released by an earthquake.
What is the Moment Magnitude Scale?
This extremely dangerous hazard consists of a fast-moving, high-temperature current of hot gas and rock that rushes down the side of a volcano during an eruption.
What is a pyroclastic flow?
Despite having a temperature of up to 6,000°C, the inner core remains in this physical state due to extreme pressure.
What is a solid?
This is why the mantle is located above the core (when thinking about the layers found in the earth).
What is the mantle is less dense than the core?
This process occurs when a denser oceanic plate sinks beneath a less dense continental plate.
What is subduction?
Magnetic minerals in seafloor rocks provide evidence that these have happened many times in Earth's history.
What are magnetic pole reversals?
This is the machine used to record seismic waves and create a seismogram.
What is a seismometer?
This substance is released into the atmosphere during a volcanic eruption, but its origin in the volcano is due the melting of the subducting tectonic plate and the plankton it drags down into the mantle as it descends.
What is carbon dioxide gas?