Earthquake Review

What are often generated when the ocean floor moves as the result of an earthquakes

tsunamis

The amount of shaking produced by an earthquake at a given location is called

the intensity

Secondary waves cannot travel through

the outer core.

List steps to explain how the epicenter of an earthquake is determined:

Find S-P time interval, Use graph to calculate distance to epicenter, Use distance for radius of a circle around a station, Find location where 3 circles intersect

What is the difference between the focus of an earthquake and the epicenter?

Focus is the first point of movement along a fault where all earthquake waves originate - it is below the surface. The epicenter is the point on the surface above the focus - the place on the surface that would receive the most intense vibrations.

List 3 things that can affect the amount of destruction caused by earthquakes.

Intensity/duration of shaking, material on which structures are built, and design of structures

What scale is most widely used by scientists for measuring earthquakes?

Moment magnitude

What is the difference between a seismogram and a seismograph and seismometer?

Seismogram is the paper record of the seismic waves. A seismometer or seismograph is the actual instrument.

secondary 11.

Shake particles at right angles to the direction the wave travels

Earth's inner core is solid because of

immense pressure

When unconsolidated sediments become saturated with water, earthquakes and turn the soil into a fluid in a process called _____. When buildings settle unevenly it gives evidence of this process.

liquefaction

How can earthquakes cause fires?

Can break gas lines and electrical lines

surface 8.

Most destructive type

secondary 7.

Only travel through solids

How many seismic stations are required to find an epicenter?

THREE

The Richter magnitude is determined by measuring

the amplitude of the largest seismic wave.

How can scientists make short-range predictions of earthquakes?

They can measure strain in rocks near faults

Small earthquakes that occur before large ones are called __________. If they occur after the major earthquake as materials adjust,

foreshocks; they are called aftershocks.

How can the ground move during an earthquake?

In any direction

Each point on the Richter scale represents a wave amplitude

10 times greater than point before it. (Example 2.3 is 10 times greater amplitude than a 1.3)

primary 10.

Can travel through the outer core

primary 9.

Compress and expand the rock they travel through

What kind of material is safest to build structures on in an earthquake-prone area?

Solid, strong bedrock like granite

How is the distance between an epicenter and a measuring station determined?

Time interval between arrival of P waves and S waves

primary 6.

Travel most rapidly

An earthquake's magnitude is determined by the

amplitude of the largest seismic wave

Earth's inner and outer core is made of

an alloy of iron and nickel

Moho:

boundary between the crust and mantle where seismic wave velocity increases

The lithosphere is made of the

crust and upper mantle and is the part of the earth divided into tectonic plates.

Most of the information about earth's interior was discovered through the study of

earthquake waves