Seismicity and Earths Interior

Question 1

Focus

Answer 1

The point within earth where the initial slippage generates earthquake energy

Question 2

Epicenter

Answer 2

Point on earths surface directly above the focus

Question 3

Seismic waves

Answer 3

Generated by an earthquake shock

Question 4

Primary waves

Answer 4

First; compressional wave identical in character to sound waves passing through liquid or gas

Question 5

Secondary waves

Answer 5

Second; particles shear or slide past one another

Question 6

Shear waves

Answer 6

Cannot pass through liquid

Question 7

Surface waves

Answer 7

Travel relatively slowly over earths surface

Question 8

Shallow focus earthquakes

Answer 8

Occur in all seismic belts. Produce larges percentage of earthquakes. Up to 70 km below the surface

Question 9

Intermediate focus earthquakes

Answer 9

Occur between 70-390 km below surface. Found at convergent plates

Question 10

Deep focus earthquakes

Answer 10

Between 300-700 km below the surface. Found at convergent plates

Question 11

Intensity

Answer 11

Destructive power of an earthquake; evaluation of the severity of ground motion at a given location

Question 12

Magnitude

Answer 12

Objective measure of the amount of energy released

Question 13

Earthquake hazards

Answer 13

Ground shaking
Surface faulting 
Submergence 
Liquefaction 
Tsunamis
Landslides
Fires
Floods

Question 14

Seismic risk map

Answer 14

Shows past earthquakes in goes of future strikes

Question 15

Mega thrust earthquakes

Answer 15

Plate of oceanic lithosphere is thrust beneath another at a subduction zone

Question 16

P wave shadow zone

Answer 16

Goes through core and refracted

Question 17

S wave shadow zone

Answer 17

Does not go through core

Question 18

Earthquake

Answer 18

Vibration of earth caused by the rupture and sudden movement of rocks that have been strained beyond their elastic limits