Earthquake Types
This type of fault occurs at transform plate boundaries where two blocks slide horizontally past each other.
What is a strike-slip fault?
This volcano is large with gentle slopes made of basaltic lava and is common at divergent boundaries and oceanic hot spots.
What is a shield volcano?
These are the fastest seismic waves and the first detected after an earthquake.
What are P-waves?
The point where rocks first move along a fault during an earthquake.
What is the focus?
Volcanoes that are not associated with plate boundaries form over these.
What are hot spots?
At divergent plate boundaries, this type of fault forms when forces pull blocks of rock apart.
What is a normal fault?
This volcano is large and steep-sided and forms from explosive eruptions of andesitic and rhyolitic lava and ash at convergent boundaries.
What is a composite volcano?
These waves move particles in a push-pull motion in the same direction the wave travels.
What are P-waves?
The location on Earth’s surface directly above the focus.
What is the epicenter?
High silica magma has this level of viscosity and typically causes explosive eruptions.
What is high viscosity?
This type of fault forms at convergent plate boundaries when blocks of rock are pushed together and the block above moves up.
What is a reverse fault?
This small, steep-sided volcano erupts gas-rich basaltic lava that piles up around a vent.
What is a cinder cone volcano?
These waves move particles perpendicular to the direction of travel and only move through solids.
What are S-waves?
The process of using at least three seismometers to locate an earthquake’s epicenter.
What is triangulation?
Low silica magma flows easily like warm maple syrup and produces this type of eruption.
What is an effusive (quiet) eruption?
Convergent (subduction) boundaries often produce this type of earthquake (in terms of depth).
What are deep earthquakes?
This large volcanic depression forms when a volcano’s summit collapses or is blown away after explosive activity.
What is a caldera?
These waves are the slowest and generally cause the most damage at Earth’s surface.
What are surface waves?
This scale measures earthquake magnitude based on ground motion and increases 10 times in shaking for each whole number increase.
What is the Richter scale?
This fast-moving avalanche of hot gas, ash, and rock can travel over 100 km/hr and reach temperatures above 1000°C.
What is a pyroclastic flow?
Divergent and transform boundaries typically produce this type of earthquake (in terms of depth).
What are shallow earthquakes?
About 630,000 years ago, the Yellowstone Caldera formed after a massive eruption from this type of volcano.
What is a supervolcano?
The fact that S-waves cannot travel through the outer core tells scientists this about the outer core.
What is that it is liquid?
This magnitude scale measures the total energy released, with each increase representing 31.5 times more energy.
What is the Moment magnitude scale?
When scientists locate an epicenter, they first calculate this by measuring the difference in arrival times between P and S waves.
What is lag time?