Vocabulary I
Type of a boundary that moves toward one point or approaching each other.
Convergent
Causes particles in the ground to move up and down, similar to ocean waves.
Why do a few earthquakes occur in the middle of continents?
Few plate margins exist in these areas.
What rises from the mantle and breaks through Earth's crust to form volcanoes?
Magma
How have seismic waves helped scientists learn about Earth's interior?
Seismic waves travel at different speeds, depending on the temperature and chemistry of the materials they move through.
Causes vibrations in the ground that result from movement along breaks in Earth's lithosphere.
Earthquake
small, steep-sided volcano that erupts gas-rich, basaltic lava.
Cinder cone
Most of earth's volcanoes occur where?
Along convergent and divergent plate boundaries.
Shield volcanoes, with gentle slopes are composed of what type of lava?
basaltic
What is the difference between volcanoes that form along convergent plate boundaries and volcanoes that form along divergent plate boundaries.
Volcanoes at divergent boundaries are basically along mid-ocean ridges. They are often shield volcanoes formed basaltic lava. Volcanoes at convergent boundaries often composite volcanoes, form from layers of lava (andesitic or rhyolitic) and ash.
Break in Earth's lithosphere where one block or rock moves toward, away from, or past another.
Fault
Volcano that is not associated with a plate boundary.
Hot spot
What scale measures earthquake damage?
Modified Mercalli scale
How do hot spot volcanoes form?
Plume
Explain why the moment magnitude scale might measure earthquake magnitude more accurately than the Richter scale.
The moment magnitude scale measures the total energy release by an earthquake, and the Richter scale uses the amount of ground motion. Ground motion can be affected by the geology of an area. As a result, it may not accurately reflect the total energy the earthquake releases.
Fastest-moving type of seismic wave; causes particles in the ground to move in a push-pull motion.
Primary wave
Liquid's ability (resistance) to flow.
Viscosity
Composite volcanoes are composed of what 2 alternating layers?
ash; layers
The eruption of an Hawaiian volcano would most likely cause what?
A basaltic lava flow
How do hot spot volcanoes form?
Plume
Travels as vibrations on and in Earth.
Seismic wave
Tiny particles of pulverized volcanic rock and glass.
Volcanic ash
What scale measures the total energy an earthquake releases?
Moment Magnitude Scale
What is the difference between types of magma that have silica content and explosiveness?
Basaltic magma has allow silica content and erupts quietly. Andesitic or Rhyolitic magma has intermediate or high silica content and erupts violently.
What parts of California have high earthquake risk?
Records show that most earthquakes occur along plate margins. California's San Andreas Fault is a transform plate boundary. When the blocks of rock on either side of this fault move, they slide past one another and earthquakes occur.