Volcanoes and Earthquakes Flashcards

Grade 6 · Science · Flashcards

Study the key terms and concepts related to earthquakes, volcanoes, and seismic activity.

Flashcards

Earthquake: Sudden ground shaking caused by the rapid release of energy when rocks along a fault slip.
Fault: A fracture in Earth's crust along which rocks on either side have moved.
Focus (hypocenter): The underground point where an earthquake originates.
Epicenter: The surface point directly above the earthquake's focus; usually the area of strongest shaking.
Seismic waves: Energy waves that radiate outward from an earthquake's focus and cause ground shaking.
Seismograph: An instrument that detects and records seismic waves; produces a seismogram.
Richter scale: A logarithmic scale measuring earthquake magnitude based on the amplitude of seismic waves.
Volcano: An opening in Earth's crust through which magma erupts as lava, gas, and ash.
Magma: Molten rock beneath Earth's surface, found in the mantle and magma chambers.
Lava: Magma that has reached and flows on Earth's surface.
Hot spot: A stationary plume of hot mantle material that burns through the moving tectonic plate above it.
Ring of Fire: A horseshoe-shaped zone around the Pacific Ocean with 90% of Earth's earthquakes and most active volcanoes.
Igneous rock: Rock formed when magma or lava cools and solidifies.
Ash cloud: A plume of pulverized rock and volcanic glass ejected during an explosive volcanic eruption.