Tectonic Forces
Boundaries
Faults and Joints
Earth Waves and Seismology
Effects of Earthquakes
100
Any shaking of the ground measurable by seismic instruments, most are too gentle for people to feel
What is an earthquake?
100
Earthquakes are most common near the edges of these
What are tectonic boundaries?
100
A crack in a rock where movement has occurred
What is a fault?
100
An instrument that both detects and records earth waves
What is a seismograph?
100
An ocean wave caused by an earthquake
What is a tsunami?
200
An instrument that simply detects earth waves
What is a seismometer?
200
Some earthquakes can occur at other places where these exist, far from tectonic boundaries
What are faults?
200
A crack in rock where there is no visible movement along the surface
What is a joint?
200
The center of earthquake activity
What is the focus?
200
This type of earthquake magnitude scale is what geologists use to report to the public, there is no upper limit, but this scale doesn't work well for earthquakes stronger than a magnitude of 7
What is the Richter scale?
300
Modern seismologists believe that faults and earthquakes are caused by this
What are tectonic forces?
300
When plate sections move apart from each other
What are divergent boundaries?
300
Transform faults are also know as these
What are strike-slip faults?
300
The fastest body wave
What is a P wave?
300
A source of danger
What is a hazard?
400
This exists when two forces acting in opposite directions attempt to slide parts of the object past each other, it is the type of stress most significant in causing earthquakes.
What is shear?
400
When plates move toward each other
What are convergent boundaries?
400
What is the fault (or fault line)?
400
These are the last waves to reach a seismic station, the two basic wave forms are Rayleigh waves and Love waves
What are surface waves?
400
The possibility of injury or death to people and damage to property, this can be reduced or eliminated
What is a risk?
500
This type of stress is a pulling motion. An example is the force that a rock climber exerts on the rope as he rappels down a cliff.
What is tension?
500
Subduction would most likely be occurring at this type of boundry
What is a convergent boundary?
500
The horizontal direction of a fault
What is the strike?
500
The point on Earth's surface above the center of earthquake activity, seismologists need data from at least three seismic stations to pinpoint the location
What is the epicenter?
500
Most earthquake-related deaths occur when man-made things fail, such as when ______________.
What is when buildings collapse?
- or -
What is when fires start due to broken gas mains or electrical wires?
600
These two properties of a material allow it to change shape without breaking under stress
What are ductility and elasticity?
600
Where plates slide past each other in opposite directions along long cracks in the crust
What are transform boundaries?
600
The angle of the fault face downward from the horizontal
What is the dip?
600
This type of body wave cannot travel through the earth's core
What is an S wave?
600
If you move up one magnitude on the Richter scale (ex. from a 6.0 magnitude to a 7.0 magnitude), the larger earthquake has about this many times more energy
What is 32 (31.6)?