Unit 3 Lesson 4 Flashcards
(24 cards)
Earthquake
Ground movement from sudden rock block shifts.
Focus
Point within Earth where earthquake motion begins.
Epicenter
Surface point directly above the earthquake’s focus.
Tectonic plate boundaries
Regions where most earthquakes occur due to stress.
Elastic deformation
Rock returns to original shape after stress removal.
Elastic rebound
Return of rock to original shape post-deformation.
Stress
Force applied to rock that can cause deformation.
Tsunami
Series of long waves caused by underwater earthquakes.
Richter Scale
Measures ground motion to determine earthquake strength.
Moment Magnitude Scale
Strength based on fault area, movement, and rock rigidity.
Modified Mercalli Scale
Describes intensity of an earthquake’s effects.
Body waves
Seismic waves traveling through Earth’s inner layers.
Surface waves
Seismic waves moving along Earth’s surface.
Site effects
Variations in earthquake impact due to geological differences.
Soil type
Influences earthquake effects based on softness and thickness.
Sediment thickness
Total sediment above bedrock affecting seismic response.
Major destruction
Severe damage from earthquakes exceeding structural limits.
Energy release
The process causing earthquakes from rock movement.
Ground motion
Movement of the ground caused by seismic waves.
Seafloor displacement
Vertical movement generating tsunamis during underwater earthquakes.
Epicenter distance
Distance from epicenter affects earthquake impact severity.
Geological variations
Differences in earth materials influencing seismic effects.
Injury and loss of life
Consequences of structural collapses during earthquakes.
Tectonic stress
Build-up of pressure at plate boundaries.
