Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Earthquakes
| Term | Definition |
|---|---|
| Stress | force that acts on rock to change its shape or volume |
| Tension | pulls on the crust, stretches rock causing it to become thinner in the middle |
| Compression | squeezes and pushes rock together until it folds or breaks |
| Shearing | pushes two masses of rock in two opposite directions, can cause masses of |
| Faults | most faults occur along boundaries, where the forces of the plate motion push or pull the crust so much that the crust breaks |
| Hanging Wall | rock that lies above the fault |
| Footwall | rock that lies below the fault |
| Normal Faults | fault is at an angle, so one block of rock lies above the fault (hanging wall) while the other block lies below the fault (footwall) |
| Reverse Faults | compression causes reverse faults. They have the same structure as a normal fault, but the blocks move in the opposite direction |
| Strike-slip Faults | rocks on either side of the fault slip past each other sideways, with little up or down motion |
| Anticline | a fold in rock that bends upward into an arch |
| Syncline | a fold in rock that bends downward to form a valley |
| Folded Mountains | mountain created from bends in the rock that create anticlines and synclines |
| Fault Block Mountain | mountain created when two normal faults cut through rock. |
| Plateau | large area of flat land high above sea level |
| Earthquake | shaking and trembling that results from movement of rock beneath Earth’s surface |
| Focus | area beneath Earth’s surface where rock that is under stress breaks, triggering and earthquake |
| Epicenter | point on the surface directly above the focus |
| P Waves | first waves to appear are primary waves that compress and expand like an accordion |
| S Waves | secondary waves that vibrate from side to side as well as up and down |
| Surface Waves | move more slowly and can produce more ground movement |
| Merchalli Scale | rates earthquakes according to level of damage. |
| Richter Scale | rating of earthquakes magnitude based on the size of the earthquake’s seismic waves |
| Moment Magnitude Scale | rating system that estimates the total energy released by an earthquake |
| Seismograph | device that records ground movement caused by seismic waves as they move through Earth |
| Tiltmeters | measures tilting or rising of the ground. It is similar to a carpenter’s level |
| Creep Meter | uses a wire stretched across a fault to measure horizontal movement of the ground |
| Laser-ranging Devices | uses a laser beam to detect horizontal fault movement |
| GPS Satellites | can monitor changes in vertical as well as horizontal movement along faults using Earth-orbiting satellites called Global Positioning System |
| Liquefaction | occurs when an earthquake’s violent shaking suddenly turns loose, soft soil into mud |
| Aftershocks | an earthquake that occurs after a large earthquake in the same area. They can strike hours, days, even months later |
| Tsunamis | water displaced by the earthquake may form a large wave |
Created by:
s730066
Popular Science sets